ABC Supply Co. Inc. Acquires the Assets of DRI Supply Co.

Building products distributor ABC Supply Co. Inc. has acquired the assets of DRI Supply Co., a distributor of drywall, roofing and insulation products. ABC will continue to serve customers from the three former DRI locations: 746 Church Hill Road in San Andreas, California; 2300 Cooper Ave. in Merced, California; and 5831 Highway 50 East in Carson City, Nevada.

The acquisition allows ABC Supply to enhance its service in both existing and new markets and strengthen relationships with professional contractors. Current DRI Supply associates will continue to work at the locations, ensuring customers receive seamless access to the products and services they need to run and grow their businesses.

“We’re happy to welcome the DRI Supply team to our ABC family,” said Matt Cooper, vice president of ABC Supply’s West Region. “Contractors will continue to work with the knowledgeable people they’ve come to know, trust and rely on while enjoying access to a wider selection of product options and delivery capabilities.”

For more information, visit www.abcsupply.com.

4 Common Causes of Inadequate Drainage on Low-Slope Roofs

Photo 1. Roof decks with poor slope, drains that are up slope and deck defection can result in excessive ponding. Images: Hutchinson Design Group Ltd.

The stone church in rural Portugal was constructed some 700 years ago. The roofs of the transepts are large stone slabs: 5 feet wide, 10 feet to 12 feet long, and 8 inches thick. How they even made it into place is amazing, but to those like us who think in terms of water, what is even more amazing is the carved-out drainage channels. Moving water off the roof was important to builders 700 years ago in Europe, just as it was to the builders of Machu Picchu and Angkor Wat. Along with many indigenous building methods, the movement of water off roofs and away from buildings is becoming a lost design element.

It is not uncommon to walk upon recently installed roofs and see ponding at gutters, roof drains and across the roof. There are many reasons for this degradation of roof system design, including ignorance. A lack of knowledge by designers, a “roofer or builder will figure it out” mentality, and poor installation procedures can all be to blame.

Ponding water provides visual evidence to the owner that something isn’t quite right, and in some instances, it can result in roof structure collapse. If breaches in the roof membrane exist, standing water can result in excess moisture intrusion. (See Photo 1.) Additionally, water on the roof promotes algae growth that can attack some materials. It also allows for ice to form in winter, creating life safety issues as well as external forces affecting the roof cover.

So, what can you do?

In this article we’ll look at four key conditions on the roof that I see as the most erroneously conceived and installed:

  1. The roof system’s transition to the gutters
  2. Two-way structurally sloped roof decks with roof drains above the low point
  3. Four-way structurally sloped roof decks with drains above the low point
  4. Roof drains on level roof decks with tapered insulation

Accumulated Debris at Gutters

As perhaps you know and will see within this article, there are many things that irk me; one is walking on a new roof and seeing a 3- to 4-foot wide swath of black accumulated dirt and airborne components in front of the gutter. This situation

Photo 2. Owners do not like seeing ponding in front of their gutters, especially when it’s egregious. Proper design and installation would have prevented this problem. Images: Hutchinson Design Group Ltd.

results from restricted water drainage, and it is especially noticeable on reflective roof covers. (See Photo 2.) This restriction of water drainage can be due to several possible factors, including roof edge wood blocking that is too high, insulation that is too low, and the accumulation of roofing material above the slope plane. The roof deck itself can also be set too low.

When designing roof edge gutters, there are key design elements to consider:

  • Wood blocking:In addition to being of appropriate width and anchorage, wood blocking should be sloped to drain, even with sloped roof decks with an elevation 1/4 inch to 3/8 inch below the anticipated roof insulation height. The greatest error I see with most architects is that they do not draw the detail to scale. Insulation is not of the correct thickness, the wood is too big or too small, or it is depicted as one giant block floating atop the wall with no mention of anchorage.
  • Insulation:Please read the ASTM standard for polyisocyanurate and you will learn that the ISO has an allowable dimensional change. Thus, if you specified two layers of 2.25-inch ISO to match three layers of two-by wood blocking, you might be in for a surprise. You might get to the field and see that your two layers of insulation are 3/8 of an inch below the top of the wood, and the manufacturer whom you’ve complained to will pull out the ASTM standard and say, “We are within tolerances.”
  • Material layering:When the roof membrane is taken over the wood (yes you should do this) and sealed to the wall substrate, and the gutter is set in mastic and then stripped in, the accumulated material thickness can exceed 3/8 of an inch. Not much, you say, but on a roof with a 1/4-inch-per-linear-foot slope, that can result in 18 inches of ponding right in front of the gutter. Ouch.

Design recommendations for achieving complete drainage at the roof edge with gutter include:

  • Communicate with the structural engineer.Coordinate with the structural engineer to determine the elevation of the wall (less wood blocking) with the structure and roof deck. If perimeter steel angles attached to the wall rise above the roof deck, discuss with the structural engineer turning the angle downward or changing the angle to one with a vertical leg that doesn’t rise above the roof deck. Angles that rise above the roof deck create a void when

    Photo 3. Even when using tapered insulation and on four-way sloped roof decks, it is advantageous to accentuate the slope into the drain. Here a 1/2-inch-per-foot tapered insulation sump matches up to the tapered insulation with the help if a 1/2-inch tapered edge strip. Images: Hutchinson Design Group Ltd.

    the first layer of insulation is set that is most often not sealed, resulting in a thermal short and a place where dew points can be reached and condensation can occur. If reinforcing paper facers are on the insulation, mold growth can result.

  • Properly detail the wood blocking. I prefer and recommend the use of two layers of wood blocking. First off, do not use treated wood; use untreated Douglas fir. The wood should be at a minimum 8 inches wide (preferably wider) so that the gutter flange can have nail locations back far enough to allow for 3-inch minimum overlap on the stripping-in ply.

Often it is best if the top of the wall is sealed prior to the installation of the wood to prevent air/moisture transport to the wood, and on precast, to prevent the migration of “damp” into the wood. The first layer of wood should be anchored to the structure (wall or framing). While not always required, I prefer to set anchors at 2 feet on center, staggered. This spacing prevents the warping of the wood. The second layer of wood should match the first in width. I suggest that this second layer of blocking be sloped, and placing a continuous shim along the roof side on the first layer will provide the proper slope. The shim width and thickness are dependent on the wood size, but for two-by-ten wood blocking, a shim of 1/2 inch by 1.5 inches will work well. The second layer of wood blocking should be set with joints offset from the lower layer and then screw fastened at 12 inches on center, staggered. Joints on both layers should be scarfed at 45degrees and screwed tight. On your detail, the height of the wood blocking at the interior side above the roof deck should be dimensioned. This will allow contractors to identify height concerns well before the installation of the insulation so adjustments can be made if necessary. I suggest that this distance be 1/4 inch to 3/8 inch below the top surface of the roof insulation or cover board atop the insulation. (See Figure 1.)

  • Make sure the insulation is higher than the wood blocking.We will not discuss insulation types, substrate boards (vapor barriers) and cover boards in this article; please see earlier articles on the topic. In designing the roof edge and discussing/coordinating with the structural engineer, the goal is to have the insulation system: substrate board, vapor retarder, cover board. The thickness should be 3/8 of an inch greater than the interior top corner of the wood blocking. One key item to remember is that spray-and-bead polyurethane adhesive adds 3/8 of an inch thickness per layer. Designing the insulation to be higher than the wood blocking is important, as it compensates for that allowable dimensional change mentioned above, as well as the thickness created by the layers of gutter flange and roofing. The goal is to create a condition in which water will flow over and into the gutter.

Two-Way Structurally Sloped Roof Decks

Often long, narrow roof areas are designed with a two-way structurally sloped roof deck designed to move water from the outer roof edge to a central point. Prudent designers would like the roof drains to be located at the low point of the structurally sloped roof deck. Typically, though, there is a steel beam at the low point, which prevents the installation of the roof drain at the low point. Consequently, the roof drains must be located on the plumbing drawings up slope from the low point. I have tried for years to explain to plumbing engineers that water doesn’t typically flow uphill, but to no avail, so we as the roof system designer have to fix it. How? By moving the low point.

How is this design goal accomplished?

Let’s start with our roof system design for the following example: a new construction project in Chicago (R-30 minimum) with a steel roof deck, two-way structural slope and the low point over a steel beam. The plans call for the drains to be installed 2 feet up slope, and thus they will be more than 1/2 inch above the low point.

The goal will be to move the structural low point to the drain line. With a structural slope, to meet the thermal value we are looking at two layers of 2.6-inch insulation. Run the first layer of 2.6-inch insulation throughout the roof. Then the fun begins: Draw a line down the center of the roof drains. From this centerline, come out 4 feet on each side with a 1/2-inch-per-foot tapered edge board (Q panel, for those who know). The next layer of 2.6-inch insulation abuts the taper. The tapered insulation at the drain line effectively moves the low point to the drains. (See Figure 2.)

Now that the water is being moved to a new low point, it then needs to be moved to the drains. This is accomplished by saddles. (See Figure 3.) Sounds simple enough, but 95 percent of the saddles I see are incorrect, and water ponds on them, over them and along them. This situation leaves, once again, a bad taste in the mouth of the owner, general contractor, construction manager, and architect — even though it’s the designer’s problem. So, I will now, for the first time, reveal my secret developed years ago: The taper of the saddles mustbe twicethe roof deck slope. If the deck slopes 1/4 inch per foot, the saddles must slope at 1/2 inch per foot. If the deck slopes at 3/8 inch per foot, as it often does, the saddle needs to be at 3/4 inch per foot. And, architects and designers, the slope of the saddle is to the valley line, not the drain. The width of the saddle is the key and determining the width of the saddle is my secret.

It’s a simple formula:

(Distance Between Drain)x 33% = X

2

Increase X to the next number divisible by 4

Example: If the drains are 60 feet apart, divide 60 by 2 to get 30 feet; multiply 30 feet by 33% = 9.9 feet. Increase 9.9 to the next number divisible by 4 to get the answer: 12 feet.

Thus, the saddles at the mid-point apex should extend out three full tapered insulation boards. It’s best if you dimension this width on the detail.

On large buildings, the saddle width and thickness can be quite high, so be sure to double-check the insulation height with the height of the roof edge. I could tell you about a roof where the insulation rose several inches above the perimeter height because someone didn’t draw the detail to scale, but that is a story for another time.

Roof Drains in Four-Way Slope Roof Decks

Structurally sloped roof decks can be beneficial in that they can create positive drainage flow. But with four-way structurally sloped roof decks, the drain is not necessarily at the low point of the roof. How far off the low point is dependent on the plumbing contractor. I have seen drains installed several feet upslope. The plumbing drawings should have a note to the fact that the roof drain sump pan should be installed as close to the low point as possible.

Even when the drain is installed very close to the low point, it is still high and will result in water ponding in front of the drain. Thus, the low point needs to be artificially moved to the drain.

This is accomplished with a drain sump. Best practices suggest that the roof insulation be installed in two layers. This will allow for the installation of the sump.

Using Chicago as an example, which calls for R-30 or 5.2-inches of insulation, the first layer of insulation 2.6 inches thick is installed across the roof deck, to the roof drain. It should be cut to the roof drain extension ring. Fill the void between the roof drain and the insulation with spray foam; trim to the insulation. Next the tapered insulation sump is installed. To match the next layer of insulation, we use 1/2-inch-per-foot tapered insulation. It starts at 1/2 inch and, with a 4-foot panel, rises to a thickness of 2.5 inches. Placed around the drain, the sump created is 8 feet by 8 feet. The next layer of insulation is 2.5 inches and abuts the backside of the tapered insulation.

The 1/2-inch-per-foot slope is used as it doubles the slope of the structurally sloped roof deck, which in this case has a slope of 1/4 inch per foot.

Level Roof Decks With Tapered Insulation

Whether re-roofing or new construction, getting the drainage correct on level roof decks is still a challenge for most designers. Perhaps they don’t realize decks are not level; they have camber, they deflect, they undulate, and the drains are often near columns so the drain pipe can run along it. When the drain is near a column where no deflection takes place, it can often be high.

I like to first ensure the proper drain assembly has been selected and designed by the plumbing engineer: the roof drain, reversible collar, threaded extension ring, clamping ring, cast iron dome. (For more detail, see “Roof Drain Installation Tips” on page XX of this issue.) The sump pan should be selected and designed by the plumbing engineer and provided by the roof drain manufacturer — not by the metal deck supplier. (That the industry cannot get this correct is one on my pet peeves.) Do not raise drains off the deck with threaded rods. (See my article “Concise Details and Coordination Between Trades Will Lead to a Quality Long-Term Solution for Roof Drains,” RoofingMay/June 2016). If designing in a vapor retarder, it needs to extend to the roof drain flange and be clamped by the reversible collar. The first layer of insulation should be cut to fit and extend under and to the extension ring. Any voids should be sealed with spray foam.

To compensate for all the potential deck irregularities, I like to accentuate the slope into the roof drain by increasing the taper. More often than not, this means designing a 1/2-inch-per-foot slope sump into the drain. With a 4-foot board, this results in an 8-foot-by-8-foot sump. (See Figure 4 and Photo 3.) After detailing this sump, the main roof four-way tapered insulation can be designed and the heights at the perimeter calculated and noted on the plans. Just a reminder that the code-required thermal value needs to be attained four feet from the drain. So, for Chicago we detail to achieve R-30 at the backside of the tapered sump.

Final Thoughts

A new roof installation that results in ponding water at the drainage point is an unfortunate occurrence. Owners can be upset: “What is that?” “I didn’t pay to have water retained at the drains!” “Who is coming up and cleaning all this stuff off my roof?” Ponding water can be a standard of care issue for designers and result in damages. Learning to properly design rooftop drainage is not difficult, but it requires some thinking and some rooftop experience. Getting up on the roof during installations will help you visualize the needs to achieve proper drainage.

Making sure the roof system drains properly requires discussions with the structural engineers for new construction. I also find it helpful to have the plumbing contractor at pre-con meetings to review the interrelationship of the roofing and drains.

Getting water off the roof as quickly as possible has been a key priority for centuries — no matter the roof cover material. If the builders using stone can achieve complete and full drainage, then I challenge you to achieve it with the materials we use today.

Accella Performance Materials Announces New Vice President

Accella Performance Materials, a Carlisle Company, has promoted Joe Negrey to Vice President and General Manager of its Spray Polyurethane Foam (SPF) Insulation business unit. Negrey will oversee all business operations—helping to advance Accella’s commitment to bringing energy-saving, cost-efficient SPF technology to the North American and global markets.

A veteran within the polymers space, Negrey has more than two decades of process engineering, product development, sales, marketing and manufacturing experience in the polyurethane systems industry. Prior to assuming this current role, Negrey served as Vice President of Accella’s Tire Fill division where, under his leadership, the brand’s foam fill product business for the Off-the-Road tire industry grew to become the recognized international category leader.

Negrey has also served in various other capacities within the Accella brand family, and held positions as Operations Manager, Director of Operations, and Vice President of Operations. His strengths lie in his visionary leadership and strategic planning capability—and excellent team management approach. Negrey holds a bachelor’s degree in Industrial Technology from California Polytechnic State University.

For more information, visit www.accellacorp.com.

Contractor Conquers Tough Weather, Tight Schedule

The roof on the new Goodman Logistics Center (the building on the right) encompasses more than 1 million square feet. The roof system installation met an aggressive timeline that spanned the winter months. Photo: Goodman Carlisle LLC

Goodman, an international commercial and industrial property group, approached Donald B. Smith Inc. of DBS Roofing in November 2017 to support the roofing of the company’s new Logistics Center in central Pennsylvania.

Founded in 1948, DBS Roofing is a second-generation, privately held company whose principles of quality and workmanship have earned the team countless awards. Among those honors include the Firestone Master Contractor recognition, the Baltimore Builder’s Exchange “Craftsman of the Year Award” and numerous industry publication recognitions for notable projects.

The Logistics Center roof was 1,010,000 square feet and was established on a very aggressive timeline that spanned through the tough Northeast winter months. The initial specifications of the job called for a mechanically fastened TPO roof system, which was going to be challenging with the size and timeline of the project. Additionally, the condensation levels in central Pennsylvania are not ideal for mechanically fastened solutions, as it would require applying a vapor barrier and foam around all perimeters, exceeding the original budget and schedule.

To save time and keep the project moving forward during the unfavorable winter conditions, DBS Roofing elected to use one of the company’s favorite “box world” solutions — Firestone Building Products (FSBP) UltraPly TPO SA with Secure Bond Technology.

Photo: Goodman Carlisle LLC

The TPO roofing system is comprised of a self-adhering membrane with factory applied, pressure sensitive adhesive and technology designed to ensure uniform adhesion coverage across the entire membrane. According to the manufacturer, the system can be installed in weather as cold as 20 degrees Fahrenheit.

“Commercial roofing in central Pennsylvania can be very challenging during the winter season, but Firestone UltraPly TPO SA allows our business to continue working through those conditions and prosper,” says Donnie Sanders, president of construction, DBS Roofing. “Being able to apply the Firestone TPO SA at 20 degrees resulted in a successful year for us.”

The Goodman Logistics Center roofing project began on November 1, 2017 and was completed on time March 1, 2018.

TEAM

Roofing Contractor: Donald B. Smith Roofing Inc., Hanover, Pennsylvania, www.dbsroofing.com
General Contractor: ARCO Design/Build Northeast, King Of Prussia, Pennsylvania, http://arcodbi.com

MATERIALS

Membrane: UltraPly TPO SA with Secure Bond Technology, Firestone Building Products, www.firestonebpco.com
Insulation: 2.5-inch ISO, Firestone Building Products

New Facility Keeps Popular Brewery Hopping

Tree House Brewing opened its new 51,200-square-foot brewery in Charlton, Massachusetts in July of 2017. Photos: Sika Sarnafil

Standing in line for hours for one case of canned beer might seem foolish to some people, but to fans of Tree House Brewing — which was recently named one of the country’s Top 15 Craft Breweries by Forbes magazine — it is well worth it. Tree House Brewing began humbly enough in 2011 in a barn in Brimfield, Massachusetts. And yes, there was a tree house on the property.

Since then, the brewery has grown so much in popularity that it required a bigger facility.  So in July of 2017, Tree House opened a 51,200-square-foot brewery on 68 acres in Charlton, Massachusetts. On opening day, the new facility consistently had 1,000 customers waiting for hours to purchase Tree House’s ales, IPAs and stouts. Many of the patrons traveled from out of state and some arrived at 6 a.m., six hours before the doors opened.

It’s been said that the key to Tree House Brewing’s success is meticulous attention to details such as temperatures, additives and the water used in the brewing. It only made sense that the same attention to detail would be utilized when selecting a roofing system for the new facility.

Meeting the Bar

The roof that Tree House Brewing selected to cover its new brewery is Sika Roofing’s Sarnafil EnergySmart PVC membrane installed with the Sarnafil RhinoBond System. “We like Sarnafil because it is easy to use, easy to specify and an industry leader,” says Peter Webster, designer/project manager at Austin Design in Brattleboro, Vermont. “The light colored, reflective roof also offers energy savings, and our past experience with the Sarnafil roof shows it is a great product.”

The roof system for the new brewery features Sika Roofing’s Sarnafil EnergySmart PVC membrane, which was installed using the Sarnafil RhinoBond System. Photos: Sika Sarnafil

The fact that the Sarnafil system is easy to install was an important factor, considering the time crunch of the project. “This was a ‘hurry up’ project — we weren’t done with the design when the steel structure went up,” Webster explains.

The Sarnafil RhinoBond System uses advanced induction welding technology to bond the membrane directly to specially coated plates used to secure the insulation to the deck, all without penetrating the roofing membrane.

In addition, the Sarnafil RhinoBond System can be used in temperatures as low as zero degrees Fahrenheit (-18°C), making it an ideal application method for winter projects.

“Much of the installation was during the winter,” states Robert Luukko, president of Kidd-Luukko Corporation in Worcester, Massachusetts, the roofing contractor on the project.

Photos: Sika Sarnafil

“Not only did Kidd-Luukko have to deal with cold temperatures, but the site is on top of a hill so there were high winds,” says Frank Quigley, president and owner of F.D. Quigley & Associates of Wilbraham, Massachusetts, the construction manager on the job. And of course, since it was winter they needed to make the building watertight as quickly as possible.

“Fortunately, Kidd-Luukko was able to seal the building before we were hit by some big snowstorms in February,” Webster says.

Other challenges included installing a 42-foot by 8-foot skylight and working around gables where the low roof wrapped around the corners. “Kidd-Luukko employees were very professional, well managed and well organized,” Quigley states. “I’d be happy to use them again.”

“Can-Do” Attitude

“Bob Luukko and his team had a ‘can-do’ attitude that really helped move the project along,” Webster comments. In fact, Kidd-Luukko was able to complete the installation ahead of the allotted eight-month time frame, Luukko notes, adding that teamwork was key. “We had weekly meetings with a great group of guys involved with the project where we would discuss how we were going to come in on time and on budget with this installation,” he says. Sika Roofing representatives also played a role in meeting the deadline. “We had multiple visits from the Sika technician, which really kept the project moving forward,” Luukko remarks.

After a vapor barrier was applied on the metal deck, crews installed polyiso insulation, tapered insulation and a high-density cover board before the membrane was attached. Photos: Sika Sarnafil

Today, both the roof and the brewery are doing great. “We’ve had no problems with the roof at all,” Webster says. Luukko adds, “This project went so well that we are receiving a lot of interest in installing Sarnafil roofs on other projects.”

At the new facility, Tree House Brewing will be able to produce 40,000 barrels a year — compared to 12,000 barrels at their former facility in Monson, Massachusetts — and they plan to eventually expand the capacity to 180,000 barrels a year. That’s news that should make thirsty Tree House beer fans very, very happy.

TEAM

Architect: Austin Design, Brattleboro, Vermont, www.austindesign.biz
Construction Manager: F.D. Quigley & Associates, Wilbraham, Massachusetts, www.fdquig.com
Roofing Contractor: Kidd-Luukko Corporation, Worcester, Massachusetts, www.kidd-luukko.com

MATERIALS

Roof Membrane: Sarnafil 60 Mil EnergySmart White PVC membrane, Sika Sarnafil, https://usa.sarnafil.sika.com
Insulation: Sarnatherm Poly-Iso Insulation and Sarnatherm Coated Glass Tapered Insulation, Sika Sarnafil
Roof Board: Sarnatherm High Density Poly-Iso roof board with coated glass facers, Sika Sarnafil
Attachment System: Sarnafil RhinoBond System, Sika Sarnafil

Easy-to-Use Discs Enable Induction Welding of PVC and TPO Membranes Over EPS Insulations

With induction welding, the membrane is heat bonded to the top of each plate and there are no penetrations in the membrane. Photo OMG

Over the past ten years, North American roofers have begun to adopt induction welding as a fast, simple and secure way to mechanically attach TPO and PVC membranes. The method also helps create a high-performance roof assembly by eliminating fastener penetrations of the membrane.

For most of its history, induction welding was limited to installations over thermoset insulations such as polyiso or over other rigid insulations with a cover board. But now, a deceptively simple and easy-to-use disc enables roofers to use induction welding over expanded polystyrene (EPS) insulations that don’t have cover boards. The result is faster and more affordable insulation installation and lower fatigue for work crews.

The Induction Welding Method in Brief

A roof fastener manufacturer pioneered induction welding attachment as a way for roofers to streamline TPO and PVC membrane installation, while avoiding membrane penetrations, for a more watertight roof assembly.

A roofing technician seals the seam with hot-air welder. Photo: Insulfoam

In a typical mechanically fastened membrane system, roofers secure the membrane with 2-inch to 3-inch diameter plates on the seams held down by screws that pass through the membrane and insulation layers to the underlying deck. With the induction welding method, each plate becomes a fastening point for the membrane, and the membrane is heat bonded to the top of each plate. With this method, crews screw down the insulation layer as usual, then unroll the membrane over the insulation. They then place a stand-up or handheld induction welding tool on the membrane at each plate location. In less than five seconds, the tool heats the plate under the membrane to about 400 degrees Fahrenheit, bonding the membrane to the plate. Heating is accomplished via electromagnetic induction between the tool and the plate, rather than via direct application of heat (think of an induction cooktop compared to conventional stove heating coils). Induction welding meets the FM 4470 approval standard and is accepted by most membrane manufacturers.

Induction welding typically requires 25 percent to 50 percent fewer fasteners and plates than typical mechanically fastened installations, as well as fewer seams, resulting in both labor and material savings. As the fasteners are spread across the roof in a grid pattern, the resulting assembly enhances resistance to wind uplift and reduces membrane sheet flutter.

EPS Insulations and Induction Welding

Until now, the induction welding process could not be used with EPS insulations that lacked a cover board, as

EPS insulations can be used in both new construction and roof recovers. Photo: Insulfoam

the 400-degree heated plates caused the insulation to soften and draw back. This resulted in numerous depressions in the roof assembly (at each fastener location), where water could pond.

To enable use of the induction welding process with a broader range of rigid foam insulations, fastener manufacturers have developed a simple solution. For each fastener, crews place a thin disc between the fastener plate and insulation. This separation medium protects the EPS from the high heat of the induction welding process, without interfering with the bond between the membrane and the fastener plate. Manufacturers typically refer to these separators as “induction welding cardboard discs.” While they are paper-based products, calling them “cardboard” understates their performance, as they are densely compressed and have a moisture-resistant coating, so they work well in high-performance roof systems.

Why This Matters

For roofers who prefer using EPS insulations for the products’ thermal performance and ease of installation, the discs allow them also to achieve the benefits of the induction welding process discussed above.

Induction welding cardboard discs enable use of the induction welding attachment process for TPO and PVC membranes over EPS insulation. Photo: Insulfoam

While induction welding has always been possible using EPS insulation products that have standard cover boards, the discs make it possible to induction weld over EPS products with glass facers and fanfold EPS with polymeric facers. Glass-faced EPS products can be used in new applications and recovers while roofers typically use fanfold EPS in roof recovers.

Fanfold EPS bundles, like R-TECH FF and others, are available in standard sizes up to 200 square feet, comprised of 25 panels that are 2 feet by 4 feet each, and come in various thicknesses. A typical two-square bundle weighs less than 11 pounds, so it is easy for one person to carry. EPS fanfold bundles require fewer fasteners per square foot than most roofing insulations and are less expensive than virtually every recover board. The man-hours needed to install fanfold bundles are about 60 percent less than working with individual sheets. Material costs are also lower than wood fiber, perlite, or gypsum board. On large projects, the

Induction welding typically requires fewer fasteners and plates than mechanically fastened applications, resulting in both labor and material savings. Photo: OMG

total savings can add up to tens of thousands of dollars. As with other EPS insulations, the product’s light weight also means less crew fatigue.

As roofers look for ways to create cost-effective, high-quality roof assemblies, new methods provide the opportunity to boost the bottom line by reducing labor and material costs. A simple, affordable disc now enables you to obtain the benefits of both the induction welding method for fastening TPO and PVC membranes and the advantages of EPS insulations.

Fasteners Designed to Attach Sheeting over Rigid Insulation

Triangle Fastener Corporation expands their line of BLAZER Drill Screws with new sizes designed to attach metal panels over rigid insulation. These unique screws have two different threads with a gap in between that eliminates jacking of the panel during installation.

Features and benefits:

  • A special ¼-14 “high thread” under the screw’s head secures the metal panel tightly against the head for optimal seal
  • Unique unthreaded section eliminates the “jacking” of the panel during installation, improving the drilling and tapping performance
  • BLAZER 3 drill point for fast penetration with less effort
  • Lengths: 1-7/8-inch, 2-3/8-inch, 3-1/4-inch and 4-inch
  • TRI-SEAL 1,000-hours salt spray coating provides over 20-times more corrosion protection than screws with commercial zinc plated
  • Available with a zinc alloy cap or stainless steel cap providing corrosion resistance in harsh environments

For more information, visit www.trianglefastener.com.

New Commercial Insulation Board Designed for High Load-Bearing Applications

Kingspan Insulation has expanded its commercial product offering by introducing GreenGuard Type VII XPS Insulation Board. The product is designed for high load-bearing engineered applications requiring insulation with a minimum compressive strength of 60 psi. According to the manufacturer, Type VII XPS is primarily used in commercial roofing applications, such as protected membrane and pedestal paver systems.

According to the manufacturer, the insulation board offers an R-value of 5.0 per inch of thickness and meets ASTM C578 Type VII requirements. The product retains its insulating properties over time, has high water resistance and is HCFC-free. In addition to commercial roofing applications, it also is suitable for low-temperature freezer floors, cold-storage facility floors, ice rinks and parking decks.

“Kingspan continues to be committed to our customers and expanding our product offerings to the North American market,” said Ryan Sullivan, managing director, Kingspan Insulation North America. “Our recent investment into a new, state-of-the-art XPS insulation manufacturing line is allowing us to increase capacity and expand our GreenGuard XPS product portfolio to include insulation board with higher compressive strengths.”

Kingspan Insulation has expanded its commercial product offering by introducing GreenGuard Type VII XPS Insulation Board. The product is designed for high load-bearing engineered applications requiring insulation with a minimum compressive strength of 60 psi. According to the manufacturer, Type VII XPS is primarily used in commercial roofing applications, such as protected membrane and pedestal paver systems.

According to the manufacturer, the insulation board offers an R-value of 5.0 per inch of thickness and meets ASTM C578 Type VII requirements. The product retains its insulating properties over time, has high water resistance and is HCFC-free. In addition to commercial roofing applications, it also is suitable for low-temperature freezer floors, cold-storage facility floors, ice rinks and parking decks.

“Kingspan continues to be committed to our customers and expanding our product offerings to the North American market,” said Ryan Sullivan, managing director, Kingspan Insulation North America. “Our recent investment into a new, state-of-the-art XPS insulation manufacturing line is allowing us to increase capacity and expand our GreenGuard XPS product portfolio to include insulation board with higher compressive strengths.”

LEARN MORE

Visit: www.kingspaninsulation.us
Call: (678) 589-7320
Email: info@kingspaninsulation.us

Single-Ply Roofing Best Practices: Doing Everything Right the First Time.

Figure 1: Designing resilient roof systems is the best of practices. When developing details, we find it very helpful to draft out the roof system (for each different system), noting materials and installation methods. Photos: Hutchinson Design Group

Single-ply membranes have risen from being the “new guy” in the market in the early ’80s to become the roof cover of choice for most architects, consultants and contractors. Material issues have for the most part been resolved, and like no other time in recent history, the industry is realizing a period of relative calm in that regard. Whether EPDM, TPO or PVC, the ease of installation, the cleanliness of the installation (versus the use of hot or cold bitumen), the speed at which they can be installed, and the material costs all blend to make these materials a viable option for watertight roofing covers. But with this market share comes issues and concerns, some of which are hurting owners, giving forensic consultants such as myself too much business, enriching attorneys, and costing contractors and, at times, designers dearly.

Following are some of my thoughts on various issues that, in my opinion, are adversely affecting single-ply membrane roof systems. Paying attention to these issues will bring about best practices in single-ply applications.

Specifying the Roof by Warranty

OMG, can architects do any less? Don’t get me started. The proliferation of “canned” Master Specs which call for a generic 10-year or 20-year warranty and then state to install the product per manufacturer’s guidelines is disheartening. Do

Figure 2: Coordinating with the mechanical engineer in the detailing of the pipe penetrations is critical. Here you can see all the components of the curb, penetrations, roofing and waterproofing are noted. We recommend that the same detail be on the mechanical sheets so that at least an 18-inch curb is known to all. Photos: Hutchinson Design Group

designers realize that manufacturers’ specifications are a market-driven minimum? When architects leave out key details, they are simply relying on the roofing contractor to do what is right. This deserves another OMG. The minimum requirements for a warranty can be very low, and the exclusions on a warranty quite extensive. Additionally, a design that calls for products to be installed based on achieving a warranty may result in a roof system that does not meet the code. Owners are often oblivious to the warranty requirements, and all too often fail to ensure the standard of care until the service life is shortened or there is storm damage — sometimes damage the roof should have withstood if it were properly designed and detailed.

If one is not knowledgeable about roof system design, detailing and specification, then a qualified roof consultant with proven experience in single-ply membranes should be retained. Roof systems and their integration into the impinging building elements need to be designed, detailed and specified appropriately for the building’s intended use and roof function. By way of example, we at Hutchinson Design Group typically design roof systems for a 40- to 50-year service life (see Figure 1); the warranty at that point is nice, but almost immaterial. Typical specifications, which are project specific, cover all the system components and their installation. They are typically 30 pages long and call out robust and enhanced material installations.

More Than the Code

I recently had a conversation with a senior member of a very large and prominent architectural firm in the Chicago area and inquired about how they go about designing the roof systems. The first thing he said was, “We do what is required by code.”

Photo 1: The roof drain sump pans shown here were provided and installed by the plumbing contractor, not the steel deck installer. Having the roof drain level with the top of the roof deck allows for a proper integration of the roof drain and roof system.

What I heard was, “We give our clients the absolute poorest roof the code allows.” An OMG is allowed here again. Does it really need to be said again that the code is a minimum standard — as some would say, the worst you are allowed to design a building by law? Maybe you didn’t realize it, but you are allowed to design above the code. I know this will shock a few of you, but yes, it’s true. Add that extra anchor to prevent wood blocking from cupping. Add extra insulation screw fasteners to improve wind uplift resistance; if too few are used, you may meet the code, but your insulation will be susceptible to cupping. Add that extra bead of polyurethane adhesive. (If I specify 4 inches on center, then perhaps by mid-day, on a hot and humid day, I might get 6 inches on center — as opposed to specifying 6 inches or 8 inches on center, and getting 12 inches on center in spots.) Plan for construction tolerances such as an uneven decks and poorly constructed walls. Allow for foot traffic by other trades. These types of enhancements come from empirical experiences — otherwise known as getting your butt in the ringer. Architects need more time on the roof to observe what goes on.

It’s About Doing What is Right

Doing it right the first time isn’t all that difficult, and it’s certainly less stressful than dealing with the aftermath of doing so little. The cost of replacing the roof in the future could easily be more than double the original cost. Twenty years ago, I

Figure 3: Coordinating with the plumbing engineer, like coordinating with the mechanical engineer, is a requirement of best practices. In this drain detail, we can see the sump pan is called out correctly, and the roof drain, integration of the vapor barrier, extension ring, etc., are clearly defined. Photos: Hutchinson Design Group

chaired an international committee on sustainable low-slope roofing. At that time, the understanding of sustainability was nil, and I believe the committee’s Tenets of Sustainability, translated into 12 languages, helped set the stage for getting designers to understand that the essence of sustainability is long-term service life. That mantra seems to have been lost as a new generation of architects is at the helm. This is unfortunate, as it comes at a time when clients no longer ask for sustainable buildings. Why? Because they are now expected. The recent rash of violent and destructive storms — hurricanes, hail, intense rain, high winds and even wildfires — have resulted in calls for improvement. That improvement is called resiliency. If you have not heard of it, you are already behind. Where sustainability calls for a building to minimize the impact of the building (roof) on the environment, resiliency requires a building (roof) to minimize the impact of the environment on the building. This concept of resiliency requires designing a roof system to weather intense storms and to be easily repaired when damaged. (Think of Puerto Rico and consider how you would repair a roof with no power, limited access to materials, and manpower that might not be able to get to your site.)

Achieving resiliency requires the roof system designer to:

  1. Actually understand that roofs are systems and only as good as their weakest link. Think metal stud parapet and horizontal base anchor attachment; only forensic consultants and attorneys like to see screws into modified gypsum boards.
  2. Eliminate your old, out-of-date, incorrect details. Lead vent flashing and roof cement cannot be used with single-ply membrane.
  3. Design the roof system integration into associated barrier systems, such as where the roofing membrane (air/vapor retarder) meets the wall air barrier. You should be able to take a pencil and draw a line over the wall air barrier, up the wall and onto the roof without lifting it off the sheet. If you cannot, you need to redesign. Once you can, you need to consider constructability and who may get there first — the roofer or air barrier contractor. Then think material compatibility. Water-based air barrier systems don’t react well when hit with a solvent-based primer or adhesive.

    Photo 2: This roof drain is properly installed along with 6 inches of insulation and a cover board. The drain extension ring is 1/2 inch below the top of the cover board so that the water falls into the drain and is not held back by the clamping ring, resulting in ponding around the roof drain.

    Perhaps the roofing needs to be in place first, and then the air barrier brought over the top of the roofing material. This might require a stainless-steel transition piece for incompatible materials. Maybe this requires a self-adhering membrane over the top of the roof edge prior to the roofing work, as some membranes are rather rigid and do not bend well over 90-degree angles. You as the designer need to design this connectivity and detail it large and bold for all to see.

  4. Design the roof system’s integration into the impinging building elements, including:
  • Roof curbs for exhaust fans: Make sure they are insulated, of great enough height, and are not installed on wood blocking.
  • Rooftop unit (RTU) curbs: The height must allow for future re-roofing. Coordinate with the mechanical engineer regarding constructability – determine when the curb should be set and when the HVAC unit will be installed. Roof details should be on both the architectural and mechanical drawings and show the same curb, drawn to scale. Be sure the curb is insulated to the roof’s required R-value. Avoid using curb rails to support mechanical equipment. The flashing on the interior side of the rails may be inaccessible once the equipment is placed. Use a large curb where all four sides will remain accessible.
  • Piping penetrations: Detail mechanical piping penetrations through the roof and support of same, where insulation and waterproofed pipe curbs are needed (see Figure 2). If you are thinking pourable sealer pocket, stop reading and go sign up for RCI’s Basics of Roof Consulting course.
  • Roof curbs, RTU, pipe curbs and rails: Coordinate their location and show them on the roof plan to be assured that they are not inhibiting drainage.
  • Roof drains: Coordination with the plumbing engineer is essential. Sump pans should be installed by the plumbing contractor, not the steel deck installer (see Photo 1), and the location should be confirmed with the structural engineer. Be sure drains are located in the low point if the roof deck is structurally sloped — and if not, know how to design tapered insulation systems to move water up that slope. Do not hold drains off the deck to meet insulation thickness; use threaded extensions. Be sure any air/vapor barrier is integrated into the curb and that the insulation is sealed to the curb. I like to hold the drain flange a half-inch down below the insulation surface so that the clamping ring does not restrain water on the surface. Owners do not like to see a 3-foot black ring at the drain, where ponding water accumulates debris (see Figure 3 and Photo 2).
  1. Understand the roof’s intended use once the building is completed. Will the roof’s surface be used for anything besides weather protection? What about snow removal? Will there be excessive foot traffic? What about mechanical

    Photo 3: Gaps between the roof insulation and roof edges, curbs and penetrations are prevalent on most roofing projects and should be sealed with spray foam insulation as seen here. It will be trimmed flush once cured.

    equipment? Photovoltaic panels? Yes, we have designed roofs in which a forklift had to go between penthouses across the roof. Understanding how the roof will be used will help you immensely.

  2. Understand the construction process and how the roof might be used during construction. It is amazing how few architects know how a building is built and understand construction sequencing and the impact it can have on a roof. I firmly believe that architects think that after a lower roof is completed, that the masons, carpenters, glazers, sheet metal workers, welders, pipe fitters, and mechanical crews take time to fully protect the newly installed systems (often of minimal thickness and, here we go again, without a cover board — OMG) before working on them. I think not. Had the architect realized that temporary/vapor retarders could be installed as work surfaces, getting the building into the dry and allowing other trades to trash that rather than the finished roof, the roof system could be installed after those trades are off the roof.
  3. Coordinate with other disciplines. Roof systems cannot be designed in a vacuum. The architect needs to talk to and involve the structural, mechanical and plumbing engineers to ensure they realize the importance of essential details. For example, we cannot have steel angle around the drain whose flange rests on the bar joist, thus raising the roof deck surface at the roof drain. Ever wonder why you had ponding at the drain? Now you know. I attempt to always have a comprehensive, specific roofing detail on the structural, mechanical and plumbing sheets. I give the other disciplines my details and ask that they include them on their drawings, changing notes as required. That way, my 20-inch roof curb on the roof detail is a 20-inch curb on the mechanical sheets — not a standard 12-inch curb, which would more often than not be buried in insulation.
  4. Detail, detail, detail, and in case you glossed over this section, detail again. Make sure to include job-specific, clearly drawn details. Every condition of the roof should be detailed by the architect. Isn’t that what the client is paying for? Do not, as I once saw, indicate “RFO” on the drawings. Yes, that acronym stands for “Roofer Figure Out.” Apparently, the roofer did not figure it out. I enjoyed a nice Hawaiian vacation as a result of my work on that project, courtesy of the architect’s insurance company. How do you know that a condition works unless you design it and then draw it to scale?

    Figure 4: Insulation to curbs, roof edge and penetrations will not be tight, and to prevent a thermal short, the gaps created in construction need to filled with spray foam, as noted and shown here in this vent detail. Photos: Hutchinson Design Group

    I’ve seen roof insulation several inches above the roof edge because, OMG, the architect wanted gravel stop and forgot about camber. Not too big a deal (unless of course it’s a large building) to add several more layers of wood blocking and tapered edge strips at the now high wood blocking in the areas that were flush, but now the face of the roof edge sheet metal needs to increase. But what if the increase is above the allowable ANSI-SPRI ES1 standard and now a fascia and clip are required? You can see how the cost spirals, and the discussion ensues about who pays for what when there is a design error.

  5. Develop comprehensive specifications that indicate how the roof system components are to be installed. This requires empirical knowledge, the result of time on the roof observing construction. It is a very important educational tool that can prevent you, the designer, from looking like a fool.

Components

Best practices for single-ply membranes, in addition to the design elements above, also involve the system components. Below is a listing of items I feel embodies best practices for single-ply roof system components:

  1. Thicker membranes: The 45-mil membrane is insufficient for best practices, especially when one considers the thickness of the waterproofing over scrim on reinforced sheets. A 60-mil membrane is in my opinion the best practices minimum. Hear that? It’s the minimum. You are allowed to go to 75, 80 or 90 mils.
  2. Cover boards: A cover board should be specified in fully adhered and mechanically attached systems. (Ballasted systems should not incorporate a cover board.) Cover boards have enhanced adhesion of the membrane to the substrate over insulation facers and hold up better under wind load and hail. Cover boards also protect the insulation

    Photo 4: The greatest concern with the use of polyurethane adhesives is that the insulation board might not be not fully embedded into the adhesive. Weighting the boards at the corners and center with a minimum of 35 pounds for 10 minutes has proven to work well in achieving a solid bond.

    from physical damage and remain robust under foot traffic, while insulation tends to become crushed. Cover boards are dominated by the use of mat-faced modified gypsum products. Hydroscopic cover boards such as fiberboards are not recommended.

  3. Insulation: Now here is a product that designers seldom realize has many parts to be considered. First, let’s look at compression strength. If you are looking to best practices, 25 psi minimum is the way to go. The 18-psi insulation products with a fiber reinforced paper facer can be ruled out entirely, while 20 psi products are OK for ballasted systems. Now let’s look at facers. If you think about it for a second, when I say “paper-faced insulation,” you should first think “moisture absorbing” and secondly “mold growth.” Thus paper-faced products are not recommended to be incorporated if you are using best practices. You should be specifying the coated glass-faced products, which are resistant to moisture and mold resistant. A note to the manufacturers: get your acts together and be able to provide this product in a timely manner.

Additional considerations regarding insulation:

  • Insulation joints and gaps: You just can’t leave joints and gaps open. Show filling the open joints at the perimeter and curbs and around penetrations with spray foam in your details and specify this as well (see Photo 3 and Figure 4).
  • Mechanical attachment: Define the method of attachment and keep it simple. On typical projects, I commonly specify one mechanical fastener every 2 square feet over the entire roof (unless more fasteners are needed in the corners). Reducing the number of fasteners in the field compared to the perimeter can be confusing for contractors and the quality assurance observer, especially when the architect doesn’t define where that line is. The cost of the additional screws is nominal compared with the overall cost of the roof.
  • Polyurethane foam adhesive: Full cover spray foam or bead foam adhesive is taking over for asphalt, at least here in the Midwest, and I suspect in other local markets as well. The foam adhesive is great. It sticks to everything: cars, skylights, clerestories, your sunglasses. So, it is amazing how many insulation boards go down and don’t touch the foam. You must specify that the boards need to be set into place, walked on and then weighted in place until set. We specify five 35-pound weights (a 5-gallon pail filled with water works nicely), one at each corner and one in the middle for 10 minutes (see Photo 4). Yes, you need to be that specific.
  1. Photo 5: The design of exterior walls with metal studs that project above the roof deck is a multi-faceted, high-risk detail that is often poorly executed. Here you can see a gap between the deck and wall through which warm moist air will move and result in the premature failure of this roof. The sheathing on the wall cannot hold the horizontal base anchor screw, and the joints in the board allow air to pass to the base flashing, where is will condense. This is the type of architectural design that keeps on giving — giving me future work.

    Vapor/air barrier: A vapor air barrier can certainly serve more than a function as required for, say, over wet room conditions: pools, locker rooms, kitchens, gymnasiums. We incorporate them in both new construction and re-roofing as a means of addressing construction trade phasing and, for re-roofing, allowing time for the proper modification of existing elements such as roof edges, curbs, vents, drains, skylights and pipe curbs. Be sure to detail the penetrations and tie-ins with wall components.

  2. Deck type: Robust roof decks are best. Specify 80 ksi steel roof decks. Try staying away from joint spacing over 5 feet. Decks should be fully supported and extend completely to roof edges and curbs.
  3. Roof edge design: A key aesthetic concern, the termination point for the roof system, the first line of defense in regard to wind safety — the roof edge is all of these. The construction of the roof edge on typical commercial construction has changed drastically in the last 20 years, from brick and block to metal stud. Poorly designed metal stud parapets will be funding my grandkids’ college education. The challenge for the metal stud design is multifaceted: It must close off the chimney effect, prevent warm moist air from rising and condensing on the steel and wall substrate, create an acceptable substrate on the stud face in which to accept base anchor attachment, and — oh, yes — let’s not forget fire issues. Tread lightly here and create a “big stick” design (see Photo 5).
  4. Roof drains and curbs: As discussed above, there is a great need for coordination and specific detailing here. The rewards will be substantial in regard to quality and efficiency, minimizing time spent dealing with “what do we do now” scenarios.
  5. Slope: Design new structures with structural roof deck slope, then fine tune with tapered insulation.

Final Thoughts

Best practices will always be a balancing act between cost and quality. I believe in the mantra of “doing it right the first time.”

The industry has the material and contractors possess the skill. It’s the design and graphic communication arm that needs to improve to keep everyone working at the top of their game.

Designers, get out in the field and see the results of your details. See firsthand how a gypsum-based substrate board on a stud wall does not hold screws well; how a lap joint may not seal over the leading edge of tapered insulation; how the roof either ponds water at the roof drain or doesn’t meet code by drastically sumping; or how the hole cut in the roof membrane for the drain might be smaller than the drain bowl flange, thus restricting drainage. Seeing issues that the contractors deal with will help you as the designer in developing better details.

Contractors, when you see a detail that doesn’t work during the bidding, send in an RFI and not only ask a question, but take the time to inform the architect why you don’t think it will work. On a recent project here in Chicago, the architect omitted the vapor retarder over a pool. The contractor wrote an explicit explanation letter and RFI to the architect during bidding, and the architect replied, “install as designed.” In these situations, just walk away. For me, this is future work. A local contractor once told me, “I don’t get paid to RFI, I get paid to change order.” He also said, “If I ever received a response to an RFI, I would frame it!”

Manufacturers, too, can raise the bar. How about prohibiting loose base flashings at all times, and not allowing it when the salesman says the competition is allowing it. Have contractors on the cusp of quality? Decertify them. You don’t need the hassles. Owners don’t need the risk.

Seek out and welcome collaboration among contractors, roof systems designers, knowledgeable roof consultants, and engineers. Learning is a lifelong process, and the bar is changing every year. Too often we can be closed off and choose not to listen. At HDG, I am proud to say we have the building owners’ best interests at heart.

By all working together, the future of single-ply membranes can be enhanced and the systems will be retained when the next generation of roof cover arrives — and you know it will.

Roof Restoration Project Brings Back Luster to Quicken Loans Arena

The 170,000-square-foot roof of Quicken Loans Arena was completely restored using a liquid-applied system from Tremco Roofing. Photos: Tremco Roofing and Building Maintenance

Re-roofing sports and entertainment venues presents its own set of challenges. Sports arenas usually host concerts and other events, so scheduling and logistics can be difficult. Quicken Loans Arena in Cleveland — also known as “The Q” — is home to the Cleveland Cavaliers of the NBA, and it hosts some 200 other diverse events every year, including concerts and conventions. In 2015, realizing the roof was reaching the end of its useful life, the owners looked for advice on their next move. A team of roofing professionals recommended a roof restoration system that would provide the protection and recreate the aesthetics of the original roof — and keep disruption to the facility at a minimum.

Ohio companies stepping up to help the home team included architect Osborn Engineering, headquartered in Cleveland; roof consultant Adam Bradley Enterprises of Chagrin Falls; roofing manufacturer Tremco Roofing and Building Maintenance, headquartered in Beachwood; and roofing contractor Warren Roofing & Insulating Co., located in Walton Hills. After comprehensive testing revealed that more than 90 percent of the roof could be restored, they developed a plan to clean, repair and completely restore the 170,000-square-foot main roof of Quicken Loans Arena using a liquid-applied system from Tremco Roofing.

John Vetrovsky of Warren Roofing and Joe Slattery of Tremco Roofing shared their insights on the project with Roofing magazine. Both men were brought in during the planning stages of the project and saw it through to completion. “We were helping to budget the project with Adam Bradley and Osborn Engineering,” notes Vetrovsky. “They were asking about a few different systems, and the Tremco system was the best fit for the project.”

Warren Roofing has served the greater Cleveland and Akron area since 1922, and Tremco’s roots in northeast Ohio go back to 1928. Warren Roofing served as the general contractor and roofing contractor on the project. The scope of work included updates to the lightning protection system, the safety cable system, and the heat trace system used to melt snow in the gutters.

Repairing the Existing Roof

The existing system was the structure’s original roof. It was 24 years old, and consisted of a mechanically attached hypalon membrane over two layers of polyisocyanurate insulation totaling 3 inches. The roof membrane was showing some wear, and sections had sustained damage from an interesting source: fireworks from nearby Progressive Field, home of the Cleveland Indians, launched after the Indians hit home runs. After the damage was detected, the team changed the direction the fireworks were launched, and the problem ended.

Crews from Tremco Roofing cleaned the roof using the company’s RoofTec system, which recaptures the water and returns it to a truck to be filtered. Photos: Tremco Roofing and Building Maintenance

Despite the damage, visual analysis and a nuclear roof moisture test using a Troxler meter confirmed the roof was an excellent candidate for restoration. “There was some wet insulation and warped insulation, and we marked off those areas that had to be replaced,” notes Slattery. “It was a small fraction of the total job.”

Crews from Warren Roofing removed and replaced the damaged insulation, cutting through the membrane all the way down to the existing 6-mil vapor barrier on the deck. “All of that insulation had to be stair-stepped back so we could properly lap in the new material,” Vetrovsky says. “We got rid of all of the damaged insulation, and we repaired the vapor barrier. Then we staggered the two new layers of insulation, matching the existing thickness.”

Where possible, the existing membrane was pulled back and glued into place. In sections where new membrane was needed, crews adhered pieces of EPDM.

The plan specified adding the fasteners in the existing roof and any repaired sections before the coating system was applied. Tremco Roofing conducted uplift testing through Trinity ERD to ensure the results met or exceeded the specified design. “There was a significant upgrade to the fastening,” Vetrovsky says. “Because of the shape of the building, the perimeter enhancement was probably the greatest I’ve ever seen.”

Screws and 3-inch plates were used. In the field, the minimum was 4 feet on center, 12 inches apart. In the perimeter, fasteners were installed 2 feet on center, 8 inches apart. “It worked out nicely because the fastening ended up in the middle of the sheet, and now the sheet has fasteners that are original at the seam, and a foot or two over, there is a row of new fasteners,” notes Vetrovsky.

Cleaning Up

Prior to the fasteners being installed, the membrane was cleaned by crews from Tremco Roofing using the company’s RoofTec system. “We cleaned the membrane no more than 30 days ahead of what Warren Roofing was doing,” notes Slattery. “We had to mobilize at least three times to clean the roof so the time elapsed would never be more than 30 days.”

The three-step restoration process consists of a primer, a base coat with a fiberglass mat embedded in it, and a topcoat. Here, crews embed the fiberglass mat in the base coat. Photos: Tremco Roofing and Building Maintenance

The cleaning solution is applied using a custom-designed tool that looks like a floor polisher. It has a 2-foot diameter head that spins to clean the surface and a vacuum that recaptures the water, which is returned via hoses to a truck so contaminated waste water, environmental pollutants and high-pH cleaning solvents can be filtered out. “All of that water goes back into the sanitary system after it’s filtered,” Slattery explains. “It does not go into the sewer system.”

“It’s very fast, it’s very effective, and it’s very efficient because you can easily see the areas that have been cleaned,” notes Vetrovsky. “With power washing, you don’t have any way to filter the water.”

The biggest challenge on the cleaning portion of the project was the arena’s sheer size. Approximately 500 feet of hoses were needed to supply water and return it to the truck for filtering.

Cleaning of the substrate is a crucial step, according to Vetrovsky. “The system really does a nice job cleaning the membrane, and that is the key to any restoration project,” he says. “You’re only as good as the surface you’re applying it to.”

Applying the New Roof System

After the sections were cleaned, crews installed the liquid-applied AlphaGuard MT system. The three-step process consists of a primer, a base coat with a fiberglass mat embedded in it, and a topcoat. In this case, the primer was applied with rollers. “The area that we primed each morning was the section we would apply the first coat of AlphaGuard MT with the fiberglass mat that afternoon,” Vetrovsky says. “We did not prime ahead. We didn’t want to take the chance of dust adhering to the primer.”

The top coat was applied with both rollers and spray equipment. Photos: Tremco Roofing and Building Maintenance

Care had to be taken with the schedule to complete the work efficiently. “Once the base coat is on, you have 72 hours to apply the top coat,” Vetrovsky explains. “We would install the base coat and the fiberglass mat for two to three days to get a big enough area. The topcoat would go on faster because you’re not embedding any mesh into it. You really had to always keep an eye on the future weather to make sure you could get the topcoat on within the 72 hours.”

The topcoat was applied with both rollers and spray equipment. After the topcoat was applied, crews installed a second coat with sand embedded in it as a wear surface. Because of the roof’s curved surface, walk pads were not feasible, so the sand was used to provide additional traction for any workers conducting ongoing maintenance.

The sand was broadcast by hand and back-rolled into the coating to maintain a uniform appearance. “Part of this project was to make sure the sand looks uniform when it is visible from a blimp overhead,” notes Vetrovsky. “That was a difficult task, but the guys did a great job.”

The roof features three different finish colors, which were custom designed to match the roof’s original color scheme. The main roof is light gray, with black under the large LED sign. The sections over the wings are white, as are the 2-foot-wide stripes.

“They wanted black under the new LED sign so it would really show the letters nice and clear, even during the day,” says Vetrovsky. “We also put the white stripes back to match the roof’s original appearance. That was a challenge, to keep everything straight. It’s hard to chalk lines on a curve, but it came out nice. Everything matches what the original roof looks like.”

Penetrations for the sign included round posts that held the rails about 2-1/2 feet above the roof level. The liquid-applied membrane made coping with details easy, according to Vetrovsky. “The liquid membrane makes the flashing details all one piece with the roof system,” he says. “We removed the existing boot flashings so that we could seal directly to the conduit or steel posts.”

Gutters, Lightning Protection and Safety Systems

The large commercial gutters also needed to be refurbished. The gutters were 4 feet deep and 4 feet wide, and were outfitted with a cable snowmelt system, which had to be removed. “The gutters had a lot of damaged insulation, so material in the gutter sections was 100 percent torn off,” notes Vetrovsky.

After the roof surface was cleaned, the restoration system was applied. The three step process consists of a primer, a base coat with a fiberglass mat embedded in it, and a topcoat. Photos: Tremco Roofing and Building Maintenance

In the gutters, tapered insulation was installed, and a cover board — DensDeck from Georgia-Pacific — was added for increased durability. New EPDM membrane was installed and cleaned prior to the three-step coating application. New heat trace cable was also installed.

The lightning protection system also required repair, and close coordination with the subcontractors was critical. “The existing lightning protection had to be removed to apply the new roof system, but we couldn’t remove it 100 percent, because we still had to have an active lightning protection system for the building,” says Vetrovsky. “We rearranged the lightning system and installed new stanchions to try to eliminate as many horizontal lines as we could.”

During construction, key to the safety plan was a perimeter barrier system, which was installed by workers who were 100 percent tied off. After the system was in place, workers inside the barricades did not need to wear personal fall arrest systems. “The entire perimeter had a barricade system put on before any material was even loaded,” Vetrovsky says. The company makes its own barricade sections, which are anchored to the parapet walls and gravel stop edges and feature a downward leg for added support.

As part of the project, crews also installed permanent safety equipment. “There was an existing tie-off system out there, but it was not a certified system and we couldn’t use it,” Vetrovsky says. “We brought that to the owner’s attention and replaced it with a new certified tie-off system manufactured by Guardian Safety.”

Challenging Schedule

Progressive Field and the Quicken Loans Arena are right next to each other, and logistics and scheduling around the stadiums was difficult. Work began in 2016 and finished in 2017, and the demanding schedule was made even more difficult when both the Indians and the Cavaliers made deep runs into the playoffs. In 2016, the Cavs became NBA Champions. But it was the Indians making it to the 2016 World Series that posed bigger logistical problems for the re-roofing project.

The restored roof recreates the original color scheme, which features three different custom colors. The main roof is light gray, with black under the large LED sign, while the sections over the wings stripes are white. Photos: Tremco Roofing and Building Maintenance

“The first part of the schedule was the most difficult, as we had the get the black coating on the roof under the sign prior to the playoffs,” Vetrovsky says. The sign covered approximately 30,000 square feet of roof area, and it was difficult to access the roof surface beneath it. “Crews had to work on their hands and knees to apply the coating beneath the steel framing. That was towards the fall, when the weather started changing, and one of the biggest hurdles was just getting the roof dry in the morning. It got colder and colder as we got down to the wire, but we made our deadline for the work under the sign.”

The staging area was also limited, and the crane could only lift material to one section of the roof. Some material had to be moved by hand some 2,000 feet. “It was an awfully long walk from one end of that roof to the other,” Vetrovsky recalls.

Concerts and other events held during the construction cycle made the schedule even more challenging. “The most notable event was probably the Republican National Convention, which totally shut the site down for more than a week because of security,” notes Slattery.

Concerts usually necessitated loading in the early morning and clearing the staging area by 8 a.m., but usually work could continue during the day. “We had to do a lot of coordination to make sure we had what we needed to work the entire day and also not go against our commitment to the owner that we would not work past certain hours,” Vetrovsky says. “Many of the special events started after 7 p.m., so we would be long gone by then.”

Championship Caliber

The project was wrapped up earlier this year. Vetrovsky and Slattery agree that the system chosen was a great fit for this project for several reasons. With restoration, there is less noise, less disruption, and less equipment than with a re-roofing project, and the roof has a warranty for the next 20 years. The process also limits negative impact on the environment by preventing removal and disposal of the old roof system.

“The weight was also a factor,” notes Vetrovsky. “With the existing structure, there wasn’t a lot of room for a different type of roof system with heavy cover boards. This roof system was perfect because it doesn’t add a lot of weight.”

The coating also minimized installation time, notes Slattery. “The disruption of a roof replacement in a hospitality setting like that, where they need 250 days of revenue stream, restoration becomes a real attractive option,” he says. “I can’t think of one day where we really disrupted anything.”

Vetrovsky points to his talented crews as the key to meeting tough schedules with top-quality production “What we can offer is skilled labor,” he says. “We’re a union contractor and our guys are well trained. The harder, the better for us. We can handle projects that most other contractors won’t even put a number to — this project being one of those.”

He credits Adam Livingston, a third-generation foreman for Warren Roofing, for his work on the project.  “With his experience and attention to detail, we were able to complete this project on time, meet the expectations of the client and Tremco, and match the unique aesthetic requirements of the roof,” says Vetrovsky. “We have a lot of great employees who take pride in their work. Take all of that together, that’s why we can be successful on projects like the Quicken Loans Arena.”

The Cavaliers taking the NBA Championship during the project only added to the excitement. “It’s a great feather in our cap,” notes Slattery. “Restoration is a growing segment of the market. Instead of letting the clock run out on these roofs, if you catch them at the right time, it can be a phenomenal way to keep costs down and it’s good for the environment because it’s not adding waste to landfills.” 

TEAM

Architect: Osborn Engineering, Cleveland, Ohio, www.osborn-eng.com
Roof Consultant: Adam Bradley Enterprises, Chagrin Falls, Ohio, www.adambradleyinc.com
General Contractor: Warren Roofing & Insulating Co., Walton Hills, Ohio, www.warrenroofing.com

MATERIALS

Roof Cleaning System: RoofTec, Tremco Roofing, www.tremcoroofing.com
Roof Restoration System: AlphaGuard MT, Tremco Roofing