Monolithic Roofing Membranes- A Full Review
Posted by Tim Simpson, Quality Assurance and Quality Control Manager, Maintenance Coatings Inspector on 24th May 2023
What Is a Seamless Monolithic Roof?
Roof care frequently seen as spot repairs instead of a defined preventative maintenance program. The result is often a decision reached by building managers and owners to completely replace a roof or to overlay the roof with a Seamless Monolithic Roof Membrane.
In this article we focus on defining a variety of roof systems along with a discussion about the pros and cons associated with the most popular systems. We will also introduce you to Ames Liquid Applied Seamless Monolithic Reinforced Membrane Roofs and offer detailed information on all our systems.
The Evolving Roofing Industry
Historically, hot tar has been used on flat roofs dating back to the mid-1800s. Although roof systems have evolved, there are still many tar roofs on older buildings that continue to be re-tarred to this day.
Thanks to emerging technology, building owners and facility managers have turned away from inefficient and non-eco-friendly hot tar applications and moved to energy efficient, long-lasting, low VOC, and sustainable roofing materials.
Interestingly, most modern roofing materials still begin as a liquid. Sheet materials are created from liquids that are converted (via heat or chemical application or both) to a solid sheet of material. These formed materials are then trimmed, cured, and rolled into sizes that can be handled by crews during installation. These materials do not combine to create a monolithic (single) roof but are instead joined at their seams by a fastening system. Although these rolled roofing materials may be reinforced at the factory, a major drawback of this manufacturing and installation process are the numerous seams and joints that, predictably, create weak spots for water to penetrate the roofing system.
These prefabricated materials can include:
- Cap Sheet – a commonly used low-cost asphaltic based reinforced rolled material with an embedded granular top surface which is similar in composition to an asphalt roofing shingle. Cap Sheet comes in a roll form typically sized so that each roll covers about 100 sq. ft. The material is unrolled into a wet bed of asphaltic-based adhesive and overlapped onto adjacent strips of cap sheet. The overlapping joints are glued together with a splicing adhesive. The granular side of the cap sheet material is face-up to provide a wear surface.
- Other Rolled Roofing Products – Various other rolled sheet materials such as EPDM, TPO, Modified Torch Down, and Vinyl are also provided in rolls which are applied in a similar manner to Cap Sheet. These other products are partially or fully glued with seams spliced by a variety of methods including the use of adhesives or heat welding. Sometimes a portion of these roof types are also ballasted with gravel.
Regardless of the method of interlocking these materials together, the common denominator of these rolled materials are numerous seams and joints. These seams and joints can result in a finished product that may need to be frequently inspected and the seam’s integrity maintained.
Monolithic (seamless) Membrane Roofing Systems
A simple and somewhat obvious workaround for the weak spots created by seams and joints in a roofing system is to have no seams at all. In a monolithic membrane system, liquid materials are applied in bonded layers to provide a fully gap-free roof surface.
Liquid applied materials are provided in a homogeneous uncured state then seamlessly applied in bonded layers to provide a fully monolithic (seamless) roof surface. Ames Research Laboratories has developed state of the art materials that deliver high performance and sustainable seamless roof systems that can perform for the life of your building.
Ames Monolithic Seamless Reinforced Membrane Roofs are superior in that roof components are combined at the project site and liquid-applied for a custom fit to the building’s roof. What results is a fully adhered protective membrane that seals out all moisture, eliminating roof leaks and the costly upkeep otherwise associated with non-monolithic systems. Periodic maintenance of this Ames Liquid Applied Roof System can extend the life of your roof for decades.
The Ames Liquid Applied Seamless Monolithic Reinforced Membrane Roofing & Roof Repair Systems are made up of multiple chemically bonded wet applied layers of elastomeric coatings and reinforcing membrane. This monolithic membrane includes Ames Maximum Stretch UV Stable Reflective Topcoats, Ames Elasto-Barrier Waterproofing Elastomeric Basecoat, Ames Seam Tape, and Ames Reinforcing Fabric. All components become an integral part of the monolithic membrane. The installed product has excellent adhesion to the existing roof deck substrate. Periodic maintenance of this Ames Liquid Applied Roof System can extend the life of your roof for decades.
Ames Research feels that – given the choice in fabrication of a reinforced membrane in our manufacturing facility, then delivering it to your project in rolls, and finally seaming all the pieces together – we prefer to deliver the materials in a liquid state along with all the reinforcing accessories to your project. Applicators then install the Seamless Monolithic Reinforced Membrane tightly adhered to your roof substrate.
Ames Liquid Applied Seamless Monolithic Reinforced Membrane Roofing & Roof Repair System
Ames® Maximum-Stretch® is a flexible, high quality rubberized acrylic elastomeric coating with reflective properties blended especially for restoration of aged and deteriorated roofs. It has been designed specifically for waterproofing and maintaining many types of existing roofs & roof substrates. Maximum Stretch is used as a stand-alone roof coating and as a topcoat in our multi-layer Roof Coating Membrane Systems.
Maximum Stretch Features and Benefits
- Reduce the temperature on the roof by as much as 88% by reflecting the sun’s rays
- Reduce the transfer of solar heat loads to the building’s interior with a thermal emittance of 0.85
- Increase the effective R-Value performance of existing insulation(s) by cooling the insulation
- Increase the efficiency of roof-mounted HVAC units through reduced demand loads
- Result in lower energy costs through reducing peak electrical demand levels
- Reduce overall roof lifecycle costs by extending the time until a full roof removal and replacement becomes necessary.
Additional Features and Benefits of Maximum Stretch:
- Has a solar reflectance index SRI between 100-110. Higher indexes result in cooler roofs.
- This means cooler inside temperatures for you and the resulting energy savings.
- Reduce the “Heat Island Effect” in the area of the roof depending on the density of adjacent roofs and pavement in proximity.
- This may qualify as a repair/restoration expense rather than a roof replacement allowing the entire cost of a project to be expensed in the year incurred. Always confer with your CPA or tax advisor regarding appropriate treatment for tax reporting.
- Ease of application of an Ames Roof System means you can choose to apply with your own personnel or have a qualified independent applicator do the job.
Life Safety Considerations
- Ames Liquid Applied Materials are lightweight
and do not add substantially to the roof load. This is an important factor to
consider if the roof has existing deteriorated materials that are close to the
roof’s load limits. Factors that can push a roof’s load limits over the edge
and increase the danger of roof collapse can include:
- Multiple layers of existing heavy roof materials installed over each other, possibly exceeding a roof’s design loads
- Adding heavy snow loads to an overloaded roof design
- A storm event producing heavy uplift or downdraft loads on an overloaded roof design
- Ames products are exceptionally low VOC and do not contribute emissions to the Earth’s growing pollution
Acceptable Substrates for Ames Monolithic Seamless Membrane Roof System:
- Existing Tar Roofs
- Existing Cap Sheet Roofs
- Existing Weathered EPDM, TPO, Urethane Foam and Vinyl Roofs
- Existing Modified Bitumen “Torch-down” Roofs*
When You’re Ready, Ames Is Ready Too
Whatever type of roof you wish to maintain, seek the advice of industry professionals. Ames Research Laboratories has been helping building and facility managers maintain their roofs for many years. We are here to assist you in evaluating your roofing needs and what maintenance system might be right for you.