When it comes to implementing green roofs into building design, the benefits can be EXTENSIVE (pun intended).

But with any sort of ecosystem, sustainability and performance is dependent upon the level of protection & care it is given.

Performing routine, preventative maintenance is essential for keeping your green roof healthy & ensuring those benefits continue.

When a green roof is complete, most of the waterproofing membrane is covered with engineered soil & vegetation, limiting any inspection of the membrane to the elements that are visible or easily accessible. All green roofs must be inspected at least twice a year, generally in early spring & late fall, separate and apart from vegetation maintenance.

Black Pearl® Cold Applied Rubberized Asphalt Waterproofing System requires less maintenance than most other types of membranes. Semi-annual, scheduled inspections are not only prudent, they are cost-effective and can save considerable expense in preserving the warranty protection and extending the life of the system well beyond the warranty period.

Green roof horticulture inspections will vary greatly from project to project depending upon the specific vegetation, depth of soil, weather conditions, irrigation, environmental conditions, and various other factors. Each project must be evaluated independently for the proper vegetation maintenance schedule. During the establishment period, a monthly inspection is generally sufficient for simple, basic, low-profile green roofs planted with sedum unless during drought periods. Drip irrigation systems will require less attention.

The following evaluation sequence is suggested for your maintenance personnel, professional maintenance services, or professional consultants for the membrane portion of the green roof.

Perimeters

Walk the perimeter of each deck and, to the extent possible, examine membrane base flashings, metal counter flashings, caulking sealants, termination bar and metal edging for mechanical damage. Even minor scrapes or punctures need to be properly repaired as soon as possible to prevent any progressive damage. Any loose metal must be re-attached properly, and all caulking must be maintained to prevent water entry around the flashing. If base flashings are bulging, check for water behind the flashing. Check masonry weeps. If water or masonry efflorescence (a whitish, chalky discoloration) is present on either side of the masonry, the source of the water entry must be determined and corrected as soon as possible.

Drains

Examine each drain and remove any debris that has collected around the drain. Ensure that drains are operative. On stone ballasted installations, keep larger stones around the drain strainer to help prevent clogging. Do not use any devices that will restrict water flow. Insure drain clamping ring is intact & tightly bolted to the sump.

Roof Surfaces

Roof surfaces should be always kept clean of debris. On stone ballasted surfaces, where the stone ballast has been displaced exposing the insulation or filter fabric, the stone and fabric must be put back into position. If stone ballast is consistently misplaced due to heavy traffic, such as near door openings or mechanical equipment, replace the stone ballast with concrete pavers.

This should also be done if building geometry and exposure results in localized stone “scrubbing” displacement from wind. Exposed filter fabric or insulation will deteriorate with direct exposure to ultraviolet rays. Inspect all concrete pavers and concrete wear slabs for signs of cracking, disintegration, or other types of breakage. If deterioration is occurring, determine the cause and institute corrective action as recommended by the manufacturer.

Penetrations

Inspect all roof top penetrations such as vent pipes, exhaust fans, skylights, AC units, etc., checking for flashing tightness to substrate, metal flashings, seams, caulking sealants, termination bars, clamping rings and other visible elements.

If a new penetration must be installed through the deck, or if there is an addition to the existing building, contact the Barrett Company for recommendations. Barrett requires that any modifications to the membrane be performed by a Barrett Approved Contractor with Barrett materials of like and kind. This is an absolute requirement if the membrane is covered by a Barrett warranty.

Repair Materials & Chemicals

All petroleum-based products and harsh chemicals should be kept off the system. Any cleaning material, solvent, animal fats, grease, some water chiller chemicals, oil, or material containing any petroleum by-product, may degrade the membrane or other components. Any time such a product comes into contact with the membrane or insulation, an inspection is required to ascertain if damage has occurred.

If the membrane comes into contact with any type of chemical, contact Barrett Company for advice, since some chemicals can degrade the membrane, insulation or fabric. Black Pearl® or Ram Mastic is recommended for emergency repairs. Do not use random petroleum-based roof products to make repairs to the membrane. Contact Barrett for emergency repair recommendations.

Click Here to download your own digital copy of the “Maintaining Black Pearl® Under Greenroof-Roofscapes®” reference guide.

Looking to hire one of our various Approved Applicators for your next project? Interested in applying to become a Barrett Approved Applicator? Click Here to learn more!

NOTE: All product literature (i.e. technical & safety data sheets, specifications, application instructions, etc.) is currently available to download from the “Resource Library” on our website. 

Before operating a rubberized asphalt melter, it is the obligation of everyone involved in its operation to know, understand, and follow all recommended safety procedures, local ordinances, and codes.

As with all safety programs, written directions and codification must be combined with individuals exercising common sense with a high awareness of safety issues. This is applicable to all personnel on a work site, not just the supervisor or safety officer.

With that in mind, the Foreman offers the following common-sense actions that are recommended for the safe operation of propane fueled rubberized asphalt melters.

Still have questions?

Do you still have questions regarding the proper preparation and/or use of propane melters, applying hot rubberized asphalt, or anything related? If so, the following resources may be of value.

National Roofing Contractors Association (NRCA)

• (800) 323-9545

Factory Mutual Research Corporation (FM)

• (617) 762-4300

National Fire Protection Association (NFPA)

• (617) 770-3000

Occupational Safety & Health Administration (OSHA)

• (202) 634-7943

• (202) 523-8017

The Barrett Company

• (800) 647-0100

Looking to hire one of our various Approved Applicators for your next project? Interested in applying to become a Barrett Approved Applicator? Click Here to learn more!

NOTE: All product literature (i.e. technical & safety data sheets, specifications, application instructions, etc.) is currently available to download from the “Resource Library” on our website. 

**All data/information used in this blog courtesy of “Construction Waterproofing Handbook | Second Edition” by Michael T. Kubal

When it comes to maintaining the roof of your home or commercial business, cold-applied coatings can be fundamental for performance and lifespan.

There are many reasons to apply a coating to your roof, though the most common is to maximize the service life by reflecting ultraviolet radiation away from the membrane. Coatings can be used with other roof repairs to restore an aged roof to a more maintainable waterproof condition, too. For many home and business owners, that is reason enough to invest in a roof coating treatment.

Understanding Roof Coatings

When determining which product is suitable for a specific project, always—and we mean, ALWAYS— examine the manufacturer’s material data sheets. Understanding the key differences between these materials can save a lot of time & money for the contractors, property owner, facility manager, and everyone else involved.

There are several types of coatings available on the commercial roofing market. However, the material formulations, uses, and application methods are all different.

Not all coatings are acceptable or compatible on all roof surfaces. Also, all pre-application preparation should be completed in accordance with the roof coating manufacturer’s requirements. As with all liquids and adhesives used in the roofing industry, proper on-site material storage is important, and all these products have a specified shelf life.

Elastomeric coatings are generally a variety of products combined to form a strong compound, known as a hybrid. New formulations of these products are introduced to the market often. Some of the most common include neoprene, silicone, urethane, and latex/acrylic. These combinations are often compatible with the most common types of roofing material, though they tend to be most often used on metal or polyurethane foam roofing.

Acrylic

Acrylic elastomeric coatings are liquid-applied and dry to form a thick, fully adhered, monolithic (seamless) membrane in situ on the roof.  Typically white in color, these coatings have the same viscosity as paint, which makes it brushable, rollable, or sprayable. Once dried, they are also fully adhered and entirely seamless.

Acrylic-based materials provide excellent resistance to radiation and hail damage and have the inherent flexibility required to withstand dimensional instability of most roof membrane surfaces. Some studies have indicated that properly formulated acrylic coatings can reduce surface temperature as much as 20°F when exposed to direct sunlight at 85°F.  Acrylic coatings are economical, provide excellent reflectivity, and are easy to work with. These coatings also, however, lose mil-thickness from weathering, require application in ambient temperature of above 50 degrees F and, in certain cases, cannot withstand ponding water.

Barrett’s Solution:

Ram Ultra-White® Energy-Star® Rated Acrylic Elastomeric Roof Coating

Ram Ultra-White Coating is a co-polymer elastomeric water-based emulsion with a brilliant white color that offers excellent reflectivity, earning it an Energy Star® rating and LEEDS credits. It provides superior UV protection, mildew resistance, color stability, weatherability, and flexibility. Ram Ultra-White® not only helps provide protection from the elements, it provides substantial reduction of roof surface temperatures and thermal stresses, significantly increasing indoor comfort and saving cooling costs. Its ability to flex and move offers the elastic qualities necessary to accommodate the movement found in most polymer modified roof membrane systems.

PMMA (Polymethyl Methacrylate)

One of the most durable of all liquid membranes, these systems cure quickly and efficiently. With the use of catalysts, inhibitors, and separate grades (summer or winter), can be applied in a wide range of temperatures. Another advantage of PMMA liquid applied membranes is that their chemical bonds allow repairs to be easily made years later if needed. Some of the manufacturers have low VOC content so it can be used in enclosed areas (e.g., indoor fountains). These systems do have a limited “pot life”, so there a higher waste factor. Typical application is with squeegees and rollers which corresponds to higher labor costs.

Barrett’s Solution:

Ram Quick Flash PMMA Polymethyl Methacrylate Roof Coating

The Ram Quick Flash PMMA roofing system is a fully reinforced, cold liquid-applied membrane system. It is based primarily upon Polymethylmethacrylate (PMMA) technology, incorporating a liquid component and a powdered catalyst, with each component curing in approximately one hour. A decorative PMMA finish can be applied as either a smooth color coating or a textured aggregate surfacing.the place of product installation. 

Polyurethane

Polyurethane liquid membranes share many of the same advantages as PMMA products, including fast cure time and relative ease of patching. The main difference between PMMA and polyurethane-based systems are the number of components. There are multi-component polyurethanes and single-component polyurethanes. Multi-component polyurethanes have a faster cure time but a shorter pot life. Single-component polyurethanes have a longer cure time, but they do not have a pot life so there is less waste. Both systems can be applied with squeegee, roller, or sprayed with a special sprayer. Application via sprayer allows for a faster rate of installation, which in turn lowers labor cost. The disadvantage of Polyurethanes is that the system has temperature limitations for application (typically between 40-50 degrees and rising), so planning and scheduling of installation is key.

Barrett’s Solution:

HyppoCoat TC Two-Component Aliphatic Polyurethane Elastomeric Coating

HyppoCoat TC is a two-component, very high solids, aliphatic hybrid elastomeric topcoat. HyppoCoat TC is odor friendly, fast-setting, rapid-curing, and can be applied to properly prepared interior or exterior concrete, plywood and metal surfaces. It is suitable for single or multiple applications in temperatures as low as 20°F (-6.7ºC). Please use the correct product grade that complies with VOC regulations as per federal, state, county, and city regulations/codes that adhere to the location of product installation.

Silicone

Silicone-based liquid roof systems, in contrast to other liquid roof systems, can be applied without the use of a primer to the substrate in most instances. They are also applied via squeegee, roller, or sprayer. Silicone exhibits a high level of dimensional stability, and extreme temperature fluctuations. It has seen a rise in popularity in the commercial market over the last decade due primarily to the material’s ability to withstand long-term exposure to ponding water, which is an issue for most other coating options. 

A silicone-based system has most of the same advantages as PMMA and Polyurethane systems but has a greater odor that could potentially limit its applications in sensitive areas/environments (e.g., hospitals and schools). Some of the drawbacks are cost, application requirements, and the fact that there are only a few materials – other than silicone – that can be applied directly to the silicone surface. Silicone also holds dirt on the surface and loses reflectivity over time. 

A silicone-based system has most of the same advantages as PMMA and Polyurethane systems but has a greater odor that could potentially limit its applications in sensitive areas/environments (e.g., hospitals and schools). Some of the drawbacks are cost, application requirements, and the fact that there are only a few materials – other than silicone – that can be applied directly to the silicone surface. Silicone also holds dirt on the surface and loses reflectivity over time. 

Barrett’s Solution:

Ram Ultra-Silver® Energy-Star® Rated Rubberized Aluminum Elastomeric Roof Coating

Ram Ultra-Silver is made of the highest quality SBS polymer-modified asphalt, premium aluminum pigment and refined solvents. When applied, aluminum flakes found in the pigment come to the surface providing a highly reflective metallic shield over the roof surfaces. This shield reduces surface temperatures and thermal movement. The SBS rubber provides elastic qualities necessary to accommodate the movement found in most polymer modified roof membrane systems. This combination of materials has proven itself as an excellent surfacing for both new and weathered asphalt built-up and modified bitumen roof systems. The reflective surfacing complies with current V.O.C. requirements and regulations. Consult the Barrett Company for specific installation recommendations for this product.

If you’re looking for a strong, waterproof, and long-lasting architectural roofing system, an asphaltic, emulsion-based membrane system is a great option. Not only will it extend the longevity of your roof, but it can also easily be applied to a number of existing roof systems. Plus, they are compatible with most other roofing membranes and coatings.

These systems are economical in nature, making it affordable to build up a membrane of sufficient thickness to stabilize most existing roof substrates. It also saves materials by utilizing your failing roof system as a base and saving landfills from additional waste.

When speaking about roofing, the terms liquid membranes and liquid coatings are often used interchangeably. While there are some similarities between the two products, there are a few key distinctions. For a more complete breakdown of the distinction between the two, check out “The Foreman’s Guide to Roof Restoration.”

Barrett’s Solution:

Ram Cold Tar® Plus Energy-Star® Rated Rubberized Aluminum Elastomeric Roof Coating

Barrett’s Ram Cold Tar® Plus roofing-grade ply adhesive & waterproofing coating is a coal tar pitch-fortified, thermoplastic SEBS polymerized surfacing compound that is specially formulated to adhere to asphalt, modified bitumen, gravel surfaced, and coal tar roofing systems. Using the existing bituminous roof mat as a substrate, Barrett’s Ram Cold Tar® Plus fuses a new, high-strength, fluid-applied rubbery membrane to the mass of the old roof mat, creating a new, double thick, elastomeric waterproof membrane. The asphaltic rubber material combines the elastic properties of rubber with the waterproof/weatherproof characteristics of a highly refined emulsified asphalt. A surface coat of Ram Cold Tar® Plus not only offers a superior flexible weathering surface, but the resistance to ponding water, a well known characteristic of coal tar.

Looking to hire one of our various Approved Applicators for your next project? Interested in applying to become a Barrett Approved Applicator? Click Here to learn more!

NOTE: All product literature (i.e. technical & safety data sheets, specifications, application instructions, etc.) is currently available to download from the “Resource Library” on our website. 

**All data/information used in this blog courtesy of “Construction Waterproofing Handbook | Second Edition” by Michael T. Kubal

Restore & Repair So You Don’t Have to Replace

Bituminous roofs and flashings oxidize and dry out as they age. Becoming increasingly brittle, they eventually split open from natural contraction and expansion cycles. These, along with other forces, cause roofs to become increasingly susceptible to moisture entry as they age.

Once moisture enters the system, the roof insulation quickly deteriorates to a point where the roofing and insulation must be completely removed before the roof can be replaced.

With timely intervention, however, it is possible to avoid the necessity of costly and disruptive roof removal.

Liquid Roof Coatings vs. Liquid Roof Membranes?

When it comes to maintaining the roof of your home or commercial business, cold-applied coatings can be fundamental for performance and lifespan.

Unfortunately, when speaking about roofing, the terms liquid membranes and liquid coatings are often used interchangeably. While there are some similarities between the two products, there are a few key distinctions.

While the distinction between the two is incredibly prevalent for understanding their uses, it certainly does not mean the two are mutually exclusive. In fact, when combined with the right roof restoration membrane, these roof coatings can restore an aged roof to a more maintainable waterproof condition while also adding a layer of UV and environmental protection.

For many home and business owners, that is reason enough to invest in a complete roof recover & rehabilitation.

An Efficient & Economical Alternative

Technological advances and labor shortages have led to the development of fluid-applied materials that can effectively extend the service life of the existing roof system at economical rate. 

Barrett’s Ram Cold Tar® Plus roofing-grade ply adhesive & waterproofing coating is a coal tar pitch-fortified, thermoplastic SEBS polymerized surfacing compound that is specially formulated to adhere to asphalt, modified bitumen, gravel surfaced, and coal tar roofing systems. The asphaltic rubber material combines the elastic properties of rubber with the waterproof/weatherproof characteristics of a highly refined emulsified asphalt. 

Using the existing bituminous roof mat as a substrate, Barrett’s Ram Cold Tar® Plus fuses a new, high-strength, fluid-applied rubbery membrane to the mass of the old roof mat, creating a new, double thick, elastomeric waterproof membrane. A surface coat of Ram Cold Tar® Plus not only offers a superior flexible weathering surface, but the resistance to ponding water, a well know characteristic of coal tar.

An efficient and economical alternative to re-roofing, Barrett’s Ram Cold Tar® Plus can save 40-60% of full roof replacement costs by extending the service life of an existing bituminous roof for years, reducing both the life cycle cost of the original roof and the energy usage of the building as a whole.

While classified as a “repair,” the result is a new, fully detailed, watertight roofing system that is guaranteed to perform.

Wall & Curb Flashing Restoration

Flashings at walls and curbs are recognized for their vulnerability to physical abuse, weather exposure and extreme movement. In other words, it’s no place to settle for second best. For guaranteed long-term performance and watertightness without all the hassle of a complete replacement, the solution is Ram Cold Tar® Plus.

Is Your Roof a Candidate?

Candidate roofs must be surveyed to determine their suitability for a recover-rehabilitation process. Insulated roofs are surveyed with a non-destructive moisture survey, either infrared or nuclear, with the results confirmed by core analysis. A review of the roof’s construction history, as well as any special conditions or considerations specific to the project are evaluated, and a project specification is generated. Before the membrane work starts, isolated wet insulation, if any, is removed and replaced with new insulation. All flashings and perimeters are fully rehabilitated.

Knowing a Roof’s Limits

Candidate roofs must be surveyed to determine their suitability for a recover-rehabilitation process. Insulated roofs are surveyed with a non-destructive moisture survey, either infrared or nuclear, with the results confirmed by core analysis. A review of the roof’s construction history, as well as any special conditions or considerations specific to the project are evaluated, and a project specification is generated. Before the membrane work starts, isolated wet insulation, if any, is removed and replaced with new insulation. All flashings and perimeters are fully rehabilitated.

**If you can do this on your roof, it is probably not eligible…

When the existing roof must be removed, The Barrett Company offers a number of high-performance roofing options, including hot or cold elastomeric BUR systems, the environmentally friendly Greenroof-Roofscapes® program, and the time-proven RamTough 250 & Black Pearl® Protected Membrane Roofing Systems.

Looking to hire one of our various Approved Applicators for your next project? Interested in applying to become a Barrett Approved Applicator? Click Here to learn more!

NOTE: All product literature (i.e. technical & safety data sheets, specifications, application instructions, etc.) is currently available to download from the “Resource Library” on our website. 

**All data/information used in this blog courtesy of “Construction Waterproofing Handbook | Second Edition” by Michael T. Kubal

THE MOST IMPORTANT PRINCIPLE OF WATERPROOFING

Each separate envelope trade contractor’s work, regardless of its being thought of as a waterproofing system or not (e.g., exterior mechanical apparatus), must become part of a totally watertight building envelope. Equally important, all individual envelope systems must be adequately transitioned into other components or provided with watertight terminations. Often the tradespeople completing this work are not aware of, trained in, or supervised in enveloping a building properly. And this is the number one cause of water infiltration in all types of structures.

The resulting improper attention to details is responsible for countless problems in construction. Properly detailing a building’s envelope presents an enormous task. From inception to installation, numerous obstacles occur. Highlighting this interrelationship of various envelope systems is the most important principle of waterproofing.

This 1 percent of a building’s exterior skin area contains the termination and transition detailing, as can be seen in the diagram below. This 1 percent area all too frequently leads to breaches and complete failure of the effectiveness of the building envelope and is the main cause of all waterproofing problems.

Industry members, including contractors, designers, and manufacturers, now are recognizing the importance of the 90%/1% principle; Architects must recognize the importance of these termination and transition detailing, manufacturers must provide the appropriate details with their specifications, and general contractors must provide the coordination and oversight of the numerous subcontractors involved in a single envelope for the completed product to perform as expected.

The 90%/1% principle is the reason that despite continuing technological advances, waterproofing continues to be one of the major causes of legal claims in the design and construction profession. It is not the actual manufactured waterproofing systems or envelope components that leak but the field construction details involving terminations and transitions.

THE SECOND MOST IMPORTANT PRINCIPLE OF WATERPROOFING

The inattention of detail is often exacerbated by overall poor workmanship that presents the next most important principle of waterproofing.

When considering the millions of square feet of waterproofing systems installed, both barrier and drainage systems, and miles of sealant involved in building envelopes, it can be estimated that only 1 percent of envelope failures and resulting leakage is actually attributable to materials or systems actually failing.

The reasons typically involved in failures include human installation errors, the wrong system being specified for in-place service requirements (e.g., thermal movement encountered exceeds the material’s capability), the wrong or no primer being used, inadequate preparatory work, incompatible materials being transitioned together, and insufficient—or in certain cases, such as with sealants, too much—material being applied.

Today, with quality controls and testing being instituted at the manufacturing stage, it is very infrequent that actual material failures occur. For example, it is rare to have an outright material failure for below-grade liquid applied membrane. More often than not, the leakage would be attributable to improper application, including insufficient mileage, improper substrate preparation, or applying over uncured concrete, among numerous other possible installation errors. Furthermore, it is likely that the leakage is also attributable to the 90%/1% principle, with inattention to proper detailing of terminations and transitions with the below-grade membrane occurring.

UNDERSTANDING THESE PRINCIPLES

These two important principles of waterproofing work in unison to represent the overall majority of problems encountered in the waterproofing industry:

Considering that these two simple principles cover most leakage problems, it would seem that preventing water infiltration problems would be easy. Certainly, prevention of envelope failures must be a proactive process implemented before each actual field construction activities commence. One of the first steps to implement this quality control process is to encourage pre-construction envelope meetings that include all subcontractors involved in the building envelope and cover the following topics:

SERVICE WITH EXPERTISE

Service with expertise is the hallmark of every Barrett warranted project. Barrett’s understanding and acquired knowledge of roofing basics and material engineering concepts, from asphalt polymerization to felt condensing techniques; from workable flashing techniques to CAD detailing, is applied to each and every project by a Registered Roof Consultant or a corporate principle. To get the best performance from our roofing and waterproofing systems, the smart choice is to use a Barrett Approved Applicator.

Looking to hire one of our various Approved Applicators for your next project? Interested in applying to become a Barrett Approved Applicator? Click Here to learn more!

NOTE: All product literature (i.e. technical & safety data sheets, specifications, application instructions, etc.) is currently available to download from the “Resource Library” on our website. 

**All data/information used in this blog courtesy of “Construction Waterproofing Handbook | Second Edition” by Michael T. Kubal

There is a significant difference between standard oxidized asphalt ASTM D-312 Types I, II, III and IV and unoxidized asphalt materials.

The ASTM D-312 products utilize a petroleum derived material called “flux” which is put into a still, heated while air is induced, which essentially ages the asphalt flux to a point that is within the softening point range of the desired end product. The composition of the flux can vary widely and directly relates to the final product’s long-term performance characteristics. These products can and do vary greatly in their performance properties, depending on their source and the competence of the processor.

Rubberized asphalt is not an oxidized material. A significant improvement over their predecessors of coal tar pitch and felt materials, hot rubberized asphalt waterproofing systems like Barrett’s RamTough 250 are fluid applied membranes consisting of a blend of asphalt and modified rubber polymers containing mineral stabilizers. It has derived its properties from chemical engineering, not from a premature aging process.

To derive the end product, the highly selected base asphalt is modified with SBS or SEBS polymer for improved water resistance and elongation, elasticity and cold flex characteristics. Crumb rubber is added to provide body, as well as enhancing the material’s flexibility properties. A small amount of filler is used to give the product the desired consistency for proper application.

When processed, this combination of components provides a product with superior moisture resistance, even under ponded water conditions, elongation and flexibility properties at temperatures below 0ºF and well below most other waterproofing products. Polymer modified bitumen also offers excellent warm temperature self-healing properties and a 40+ year proven record of superior performance. They are monolithic, seamless, fully adhered systems that can withstand constant immersion in ponded water, thermal cycling, corrosion, and any potential damage caused by soils, microorganisms, and chemicals.

Applications

Hot fluid-applied asphalt waterproofing can be applied on horizontal or vertical structures. There are numerous construction applications in which it can be utilized, including but not limited to:

Benefits of Rubberized Asphalt

Hot rubberized membranes were designed in order to provide effective waterproofing for large surface areas. They excel in conditions with intricate transitions and, when they are applied correctly, the benefits are outstanding.

Using a hot rubberized asphalt waterproofing system eliminates seams, thus reducing potential issues with detailing transitions on systems such as roofs. Additionally, the material drastically reduces the risk of leaks and provides the ability for much more aesthetically pleasing finishes.

Fluid-applied materials also provide particular advantages in vertical applications. They are easier to install than regular sheet membranes, and because they are liquid, they can fill naturally occurring imperfections, becoming a part of the existing substrate. However, extreme caution should be taken when applying hot rubberized asphalt to vertical surfaces. 

Can’t Take the Heat?

The primary issue people tend to have with hot asphalt applications comes from the added material preparation time. SBS polymer modified bitumens are heat sensitive and must be heated in equipment designed for this purpose. Unlike the traditional roofers’ kettle, a bitumen melter has a double jacketed design and uses hot oil or hot air to transfer a more even heat to the material. A melter also has an agitator which must be in constant operation to help keep the material at an even temperature.

The maximum heating temperature for Barrett’s RamTough 250 bitumen is 400°F under summer conditions and 425°F in colder winter conditions. Most contractors target 375°F as the ideal temperature during spring, summer and fall temperatures. The SBS polymer material is heat sensitive and should not be held at elevated temperatures for prolonged periods of time.

While all of this might seem like added time to the overall schedule of the project, it is important to consider that fluid-applied applications are often much less labor-intensive compared to installing pre-formed sheet membranes. It can save some projects up to 60% in labor costs. Less labor means less time, so construction schedule timelines can often be greatly reduced.

NOTE: All product literature (i.e. technical & safety data sheets, specifications, application instructions, etc.) is currently available to download from the “Resource Library” on our website. 

Cold Process Systems consist of multiple plies of reinforcement sheets that are set in a cold adhesive (solvent based or water based).

These systems are often referred to as cold process BUR systems because the application procedures are similar to hot applied BUR systems. The most common reinforcement felts are manufactured from fiberglass or polyester, which is either stitch bound or spun bound.

One of the primary advantages of cold process roof systems is their relative ease of application. Very little equipment is required, and most applications can be completed by just three or four workers. The systems can be completed as new or remedial construction or can be applied over existing smooth-surfaced roof systems in an effort to extend the service life of an existing roof system.

Barrett’s Cold Process Solutions

While Barrett has multiple cold applied systems available, our primary systems for cold process BUR & roof restorations are built around the following products:

• Ram Cold Tar® Plus | Coal Tar Fortified Asphalt
• Ram CP-80 | SBS Modified Asphalt
• Ram 40 | Trilaminate Polyester/Fiberglass Reinforcement Fabric
• Ram 306 | Granular Cap Sheet
• Ram Ultra-White® Coating | Energy-Star® Acrylic Surface Coating
• Ram Ultra-Silver® Coating | Energy-Star® Aluminum Surface Coating

Ram Cold Tar® Plus is a coal tar fortified roofing-grade ply adhesive and waterproofing coating. Ram CP-80 is a SBS polymer modified asphalt-based roofing grade ply adhesive and coating. Used as a ply adhesive, Ram Cold Tar® Plus assures total adhesion of the membrane reinforcement plies, providing the completed membrane assembly with superior strength and durability.

Ram 40 ply sheet is a trilaminate of polyester and fiberglass. This combination is one of the strongest membrane reinforcement products available for roofing installations.

Polymer modified and coal tar fortified, a surface coat of Ram Cold Tar® Plus not only offers a superior flexible weathering surface, but the resistance to ponding water, a well know characteristic of coal tar. Both Ram CP-80 and Ram Cold Tar® Plus membrane roofing systems have been designed for when cold application and optimum performance are required.

Common Cold Process Applications

Generally, the application procedures vary based on the needs & specifications of the project in question.

However, these are some of the most common applications available with Barrett’s Cold Process systems:

NOTE: All product literature (i.e. technical & safety data sheets, specifications, application instructions, etc.) is currently available to download from the “Resource Library” on our website. 

A well-designed green roof assembly, whether extensive or intensive, involves a series of functioning layers that must succeed in achieving the following:

The success of a green roof relies heavily on the performance of the waterproofing system. In addition to preventing water ingress, waterproofing systems must also be able to provide the building with thermal performance, roof drainage, air tightness & vapor control, and protection from any structural damage caused by root penetration. To ensure that the waterproofing membrane is protected, these systems will typically include a root barrier.

Root barriers can be used to create a protective barrier, either chemically or with a physical sheet, between the vegetation and the waterproofing membrane to protect from potential roof penetration. Physical barriers are made from dense, inorganic materials that will not break down due to bacterial activity or allow roots to penetrate. Chemical barriers contain a compound that stunts root growth on contact and therefore do not allow roots to penetrate the surface of the waterproof membrane.

Today, root barriers installed on green roofs are most commonly made of low and high-density polyethylene, often abbreviated to LDPE and HDPE. This doesn’t come as much of a surprise, especially when considering that HDPE makes up 47% of the material in all plastic milk, water, and juice bottles in the U.S. 

In addition to being a lightweight, pliable, heat weldable, and fully recyclable material, HDPE also offers outstanding tensile strength, moisture resistance, and the ability to withstand extreme temperatures. Naturally, it has proven to be a great material for green roof root barriers.

Barrett offers a number of root barriers to be used with our Greenroof-Roofscapes®, each offering their own features and benefits based on their recommended application.

Root Barriers for Low Profile (Extensive) Greenroof-Roofscapes®

RB20 (20 mil) is the most common root barrier product used for extensive green roof systems. It is a low-density polyethylene sheet that is ideal for systems that have typical green roof plants such as sedums, which have shallow roots and will not present a lot of penetration pressure.

Root Barriers for High Profile (Intensive) Greenroof-Roofscapes®

RB30 (30 mil) is a high-density polyethylene sheet most common in intensive green roofs and roof gardens that will have more aggressive and larger plants like perennials and grasses. The thicker sheet provides additional protection and peace of mind that roots will not penetrate.

Root Barriers for Specialized High Profile (Intensive) Greenroof-Roofscapes®

RB40 (40 mil) is a heavy-duty high-density polyethylene sheet that is recommended when very aggressive rooting plants are installed. This product has been used effectively with bamboo, but we recommend caution when installing bamboo on any roof due to the aggressive nature of the root system. 

*For questions regarding RB40 applications, please contact a Barrett technical representative directly.

All Barrett root barrier products are installed in a similar manner, typically lapping the proceeding sheets a minimum of 12 inches and taping all joints with Barrett’s RB 25 Seam Tape. The barrier is to be turned past the top of the growing media to avoid roots growing around the edges of the sheet. Taping the edges is an extra measure of assurance.

These products are not biodegradable when covered and are intended to provide protection from root penetration during the life of the green roof assembly. This type of root barrier is FLL compliant. Similar to ASTM in the United States, the German FLL is an organization that has been developing and standardizing green roof technology for over 30 years.

When properly installed within one of our hot asphalt RamTough 250 and/or cold asphalt Black Pearl® Greenroof-Roofscapes®, these root barriers provide a comparatively inexpensive solution for membrane protection without compromising performance or quality.  With warranties available for up to 20 years, the solution for any green roof assembly is Barrett’s Greenroof-Roofscape®.

NOTE: All product literature (i.e. technical & safety data sheets, specifications, application instructions, etc.) is currently available to download from the “Resource Library” on our website. 

Using ice melting compounds to clear snow and ice from plazas, drives, public entryways, and other pedestrian & vehicular traffic surfaces is virtually a universal practice today. Facility maintenance personnel learned long ago that to achieve safe surfaces in the shortest time with the least total cost, ice melters are a necessity.

This is also common practice for bridge decks. In regions where snow and ice are common during the winter months, deicing salts are used to treat hazardous road conditions. The chloride ions from the deicing salts can travel with the water through the permeable concrete structures and begin attacking the exposed steel underneath.

The corrosion caused by this attack leads not only to weakened steel but also can contribute to spalling of the surrounding concrete. This results in deterioration of the load-carrying capacity as well as the quality of the riding surface of the bridge. Waterproofing membrane systems are vital for combating this specific type of accelerated deterioration in bridge decks.

Unfortunately, whenever a product category gains such widespread acceptance, the market attracts a host of suppliers looking to capture a share. As a result, there are more than 100 brands of ice melters available today, many of which are packaged with no mention of their chemical composition.

Because of this, we cannot offer a simple, all-encompassing answer. We can, however, confirm that RamTough 250 membranes will withstand exposure to both calcium chloride and sodium chloride (or “rock salt.”), the two most extensively used deicing materials in applications around commercial, industrial, and institutional facilities.

We recommend exercising caution with liquid applied deicing agents, as some also contain solvent carrying agents that can be detrimental to the assembly. Since the installation of the Ram-Tough membrane is often in conjunction with extruded polystyrene insulation, concrete surfacing, paver systems, drainage mats, as well as other materials installed above the membrane system, consideration should be given to those materials as well. The same holds true for Barrett’s drainage mat products.

We have talked with the major suppliers of extruded polystyrene insulation and they have confirmed their product is unaffected by both calcium chloride and sodium chloride deicing agents. Because of the wide variety of concrete and paver systems available, if there is a concern, Barrett suggests the suppliers be contacted for their recommendations.

What about Greenroof Installations and other Vegetated Areas?

If deicing is necessary for traffic surfaces adjacent to vegetated areas, care should be taken to avoid having the deicing material come into contact with the plants and growing media. Alternatively, we recommend selecting a deicing product that is vegetation friendly.

There are a variety of newer materials coming on the market which claim to be more environmentally friendly. If there is an interest in any of these products, please provide us with the product literature and Material Safety Data Sheet and our Technical Services Department will review.

NOTE: All product literature (i.e. technical & safety data sheets, specifications, application instructions, etc.) is currently available to download from the “Resource Library” on our website. 

It is important to understand what may be encountered during cold weather applications and what material and manpower limitations exist. Following these cold weather suggestions will help provide greater application efficiency and system performance.

Acceptable weather conditions are based not only on the actual ambient temperature, but a total combination of elements (e.g., wind, humidity, frost, dew and precipitation). The “wind chill” factor will have a great deal of influence not only on materials, but also on workmanship. Careful planning of work during cold weather will improve the quality of the installation. Laying out the roof area and placing materials where they will be needed prior to application will lessen problems associated with cold weather application.

Where different grades of materials are specified for summer or winter use, the grade specified for cold weather should be used.

Applying RamTough KLB-100 Polymer-Modified Elastomeric Roofing Bitumen

At the point of application of the roofing plies, the mopping asphalt should be at the recommended temperature. Failure to keep the asphalt in the proper application temperature range will result in poor ply adhesion, slippage and over usage of material.

The maximum heating temperature in the summer should be 500°F and in the winter, 525°F. The EVT of 125 cP (centipoise) with KLB-100 is generally around 500°F. However, the ideal viscosity of SEBS modified asphalt is approximately 180 cP, which occurs at about 450°F.

To compensate for the rapid cooling of mopping asphalt in cold weather, it is extremely important to keep the asphalt within the specified range, but never less than 400°F and not greater than 525°F at the kettle.

SEBS modified bitumen material is heat sensitive and should not be held at elevated temperatures for prolonged periods of time. If bitumen usage throughout the day is expected to be of limited quantity, consider using a smaller kettle or keeping a smaller volume of material in the kettle to avoid prolonged heating of the bitumen that could occur in a large kettle or tanker.

Felts must be installed into the hot mopping as rapidly as possible to guarantee adequate embedment. Mopping should not precede the roofing plies by more than five feet to prevent premature cooling of the bitumen. Brooming the felts in place immediately is very important.

Proper insulation of all asphalt handling equipment is required to keep bitumen at an appropriate application temperature in cold weather. The use of insulated rooftop equipment for transporting asphalt across the roof, such as hot luggers and mop buckets, is recommended.

This is especially important when bitumen is being transported over long distances on the roof. Bitumen pumping lines from the kettle to the roof should also be insulated, as they tend to clog in colder temperatures.

Ultimately, Barrett does not recommend installing built-up roofing applications below 25°F under any circumstance.

Roof Membrane Application Precautions

Asphaltic base sheets, plies and cap sheets become less flexible in cold temperatures. Rolls should be stored on end and when possible, in a warm (>50°F) and dry location prior to application. As the work progresses on a day-to-day basis, it is essential that each section of the roof be completed as specified. “Phased construction is not acceptable”.

Applying RamTough 250 Hot Rubberized Asphalt Waterproofing Bitumen

RamTough 250 bitumen can be installed at 0°F. However, the installation techniques become critical. Use approved double-jacketed melters with mechanical agitation. Begin melter warm-up early enough to have hot fluid material when the work is scheduled to start. Cold weather start-up will take longer.

Regulate melter to maintain material temperature range of 375°F to 400°F, with constant agitation. Do not overheat RamTough 250. To compensate for the rapid cooling in cold weather, it is extremely important to keep the Ram-Tough 250 within its specified range, never less than 350°F and never greater than 425°F. It is important not to hold RamTough 250 material at elevated temperatures for prolonged periods of time. Generally, the upper limit recommendation is four (4) hours at 400°F.

At the point of application, the RamTough 250 bitumen should ideally be 325°F-375°F. Failure to keep the RamTough 250 at the proper application temperature could result in excess material usage.

When applying a RamTough 250DM system, the reinforcing ply must be installed before the bitumen cools to assure adequate embedment. RamTough 250 should not precede the reinforcing ply by more than five feet to prevent premature cooling of the bitumen.

Proper insulation of all RamTough 250 handling equipment is required to keep bitumen at an appropriate application temperature in cold weather. The use of insulated rooftop equipment, such as hot luggers and buckets, is highly recommended for transporting the bitumen to the worksite. This is especially important when bitumen is being transported over long distances. Bitumen pumping lines from the melter to the work location are not recommended with RamTough 250, as they tend to clog in colder temperatures.

Pail materials, such as cements and coatings, should be properly stored with tight-fitting lids to prevent moisture intrusion or other forms of contamination. Use winter grade material and store in heated space if possible.

Applying Ram Ultra-White® and Other Water-Based Coatings

Water-based coatings must be stored in a warm (>35°F) location to prevent freezing. Should any material freeze, be sure to properly discard it.

It is recommended that these products be applied when temperatures are 40°F and rising and that temperatures will remain above freezing until the material has cured sufficiently. Depending on weather conditions, cure time can range from 24 to 48 hours or more.

Applying Solvent-Based Coatings

• Ram Cold Tar® Plus
• CP-80 Cold Process Adhesive
• Ram Ultra-Silver®
• Ram Primer Surface Conditioner
• Ram Mastic

Although not susceptible to freezing, these bituminous based coatings will become stiff and harder to apply at colder temperatures. It is recommended that the application temperature for these products be 40°F and rising.

Storing materials in heated storage until the time of application will make application easier and require less material. Care should be taken not to apply these materials heavier than recommended. Heavy applications will effect cure time and contribute to other performance problems.

HANDLING RECOMMENDATIONS

NOTE: All product literature (i.e. technical & safety data sheets, specifications, application instructions, etc.) is currently available to download from the “Resource Library” on our website.