Whether it’s a multi-story building or a single-story home, roofs are major contributors when it comes to the safety and aesthetics of a building. From sub-zero temperatures and relentless snow and ice, to sweltering heat and intense UV rays, the roof of a building goes through a lot. The cold Winter weather in particular can take a toll on roofing systems.
When it comes to choosing the best type of material that looks great and protects the roof from damage in freezing temperatures, informed contractors and homeowners often choose a cold-weather self-adhered roof membrane system.
Do these membranes really work and are they truly any different from traditional roofing solutions? This information offers answers to help you decide on a cold-weather roofing membrane and even discuss how to install them for your upcoming roofing project.
Why a Cold-Weather Membrane?
When it comes to roofing, making informed decisions is important to ensure longevity and durability. Adhesion is one of the greatest factors that can greatly impact the integrity of a roof.
Adhesion, or the bond between two materials or surfaces, is a critical component in the overall performance of a roofing system. In cold weather conditions, the adhesion properties of roofing materials can be impacted, leading to poor performance, potential leaking issues, and other forms of damage.
It is critical to find a suitable membrane with the required adhesive characteristics to be successfully installed and perform in cold-weather environments. Property owners and contractors should take the necessary steps to ensure their roofs are protected and secure.
👉Also read: Cold Weather Roofing Systems for Low-Slope Roofs
Impact of Cold Weather on Traditional Roofing Adhesion
- Rigidity and Cracking
Extreme cold temperatures can cause roofing materials, such as asphalt-based products, to become more rigid and crack, reducing their effectiveness and allowing water to penetrate the roof deck.
- Ice Damming
Freezing temperatures can cause snow and ice to build up on the roof, during periods of freeze/thaw, water refreezes creating ice damming to voids and laps which can cause leakage and water damage.
In harsh cold weather conditions, many roofing materials can become rigid and brittle, making them more susceptible to fracture and cracking. Low temperatures can also cause roofing materials to lose their flexibility, impacting performance and longevity.
How Are Cold Weather Self-Adhered Membranes Different?
The science behind cold-weather self-adhered membranes lies in their construction and the quality of materials used. Such membranes are designed for improved installation and to provide superior protection for roofs, even in harsh cold-weather conditions.
Typically made from a combination of Styrene-Butadiene-Styrene (SBS) modified asphalt, a strong polyester reinforcing mat and elastomeric adhesive compound, these membranes withstand cold-weather conditions without the typical issues experienced with non-modified membranes.
The rubberized asphalt used in self-adhered membranes is specially formulated to remain flexible and adhere to the roof deck even in colder temperatures. This is accomplished by adding special additives to the asphalt compound, which help to reduce its brittleness and maintain its adhesive properties even in cold weather.
In addition, the self-adhesive nature of these membranes is an important factor in their effectiveness in cold weather. They are designed and can be applied directly to an acceptable substrate without the need for additional fasteners or solvent-based adhesives.
When properly handled and installed, cold-weather self-adhered membranes create a seamless, waterproof barrier that protects the underlying substrate from moisture damage, even in harsh cold-weather conditions. Their superior adhesion and flexibility make them an ideal choice for professionals and homeowners looking for a reliable, long-lasting roofing solution.
A Difference in Durability and Performance
As the temperature drops below zero, it can affect the adhesion of roofing materials. In such conditions, regular oxidized asphalt could become brittle and crack, where modified asphalt in cold weather membranes like Elastoflex SA V Polar Base® remains unaffected.
A comparison of traditional asphaltic and specifically designed cold-weather SBS modified asphalt membrane below will help show the difference.
- Traditional Roofing Materials
Traditional roofing materials, such as traditional membrane base sheets, ply sheets and cap sheets, utilize an oxidized asphalt compound which offers little flexibility, especially in cold-weather, resulting in brittleness and cracking which can result in adhesion failure to surfaces and leakage.
- Cold-Weather Self-Adhered Membranes
Cold-Weather self-adhered membranes are designed to remain flexible and adhere to the substrate even in extremely colder temperatures. The use of components like specially formulated rubberized asphalts allow these to adhere even in less than favorable weather conditions.
Cold Weather Performance
- Traditional Roofing Materials
The materials used in traditional roofing solutions are not specifically designed to withstand cold temperatures and can become brittle, shrink, and crack in subzero temperatures.
- Cold Weather Self-Adhered Membranes
Specially designed cold-weather membranes remain flexible and adhere to the substrate surface, even in freezing temperatures.
Installation of Cold-Weather Self-Adhered Membranes
Installing cold-weather self-adhered membranes isn’t as complicated as other traditional systems, however it does require a series of steps to be followed. Below is a summarized process of installing these membranes for maximum performance and longevity.
Step 1: Surface Preparation
Whether you are installing self-adhered membranes or using traditional roofing solutions, proper and thorough surface preparation is important to achieving a proper bond of the materials.
- Cleaning the Roof
Before installation of any roof system component, the roof should be cleared of all dirt, dust, debris, and free of surface moisture. Use of a broom or mechanical blower is usually suitable to remove large and loose materials that may interfere with the adhesive. For items such as oils or curing compounds may require use of a pressure washer to be sure any latent material is cleaned away.
- Inspecting the Roof Surface
It’s important to check for any damage or weak spots in the roof deck that may need to be repaired prior to roofing installation. This may include any cracks or voids in the concrete deck, rusting or loose panels of a metal deck, water damage or cracking of wood decks and other organic type decking.
- Making Necessary Repairs
Repair any and all areas that are prone. Fixing such areas before installing any roofing components, be it thermal insulation or membrane roof components.
Step 2: Priming the Substrate Surface
Depending on the substrate surface, many surfaces require the application of a primer to aid in adhesion. It is important to consider all conditions when choosing the proper primer to use. Primers will enhance adhesion and can simplify installation of materials.
It is important to remember that any primer needs time to dry before the subsequent materials can be installed. Drying or cure times will vary with the primer, surface conditions and climatic conditions.
Step 3: Rolling Out the Membrane
This is an important step of the process, as it can substantially impact handling and installation of the membrane and its performance. Industry experts recommend the following steps when rolling out the membranes.
- Start at the Low End of the Roof
Begin unrolling the self-adhered membrane at the low end of the roof and work your way up-slope. This will help prevent wind from causing the membrane to lift or shift and ensure water run over the top of or parallel to all membrane laps.
- Overlap the Seams
As you place the membrane prior to installing, make sure to keep the alignment of all sheets straight. Ensure to maintain a minimum 3 inch side lap and minimum 6 inch end lap. This helps ensure a tight, secure fit and helps prevent any water from penetrating the seams.
Step 4: Trimming the Membrane
- Cutting the Membrane to Size
A straight blade utility knife can be used to cut the self-adhered membrane to the appropriate sizes. Make sure to leave enough excess membrane to maintain all laps and carry up cant-strips and penetrations.
When cutting mineral surfaced membranes a hook blade utility knife is usually best to provide the easiest cut.
Ensure to cut required 45 degree angle cuts at all T-joints and similar conditions.
- Placement and Installation of the Membrane
Once membrane pieces are cut to a usable length for best handling, and sheets are allowed to relax, installation of the membrane can begin. Align the membrane pieces maintaining all lap requirements and removed release film from the back surface one half at a time.
- Applying Pressure to the Membrane and Laps
With a minimum 75 lb weighted roller, apply pressure to the field of the membrane sheet followed by rolling of the lap seams. Multiple strokes of rollers may be required, depending on the thickness of the membrane and how well the seams bond with each other. Pay special attention at all lap joints to ensure they are sealed, probe and reroll as needed to any incomplete bond at laps.
Elastoflex SA P Polar Cap membranes from Polyglass come with SEALLap – a granule-free and self-adhesive compound at the side lap and FastLap – a granel-free end lap design both a standard feature on SA cap sheets. These Polyglass product features offer a superior lap.
Step 5: Final Check – Inspecting the Roof and Repairing Issues
Walk the entire roof paying special attention to laps and detail work. As needed, probe any suspect laps and reroll using a hot air welder if needed to warm the membrane. If there are any issues, fix them immediately.
Polyglass Cold-Weather Self-Adhered Roofing Membranes
Cold-weather self-adhered membranes are durable and can offer better performance than traditional roofing solutions. Roofing contractors, architects, and homeowners should be aware of all the practical and economic benefits of installing self-adhered membranes in areas that experience winter weather.
Polyglass Cold-Weather Self-Adhered Membranes are a best choice for most roof designs in colder climates.
Not All Cold-Weather Self-Adhered Membranes Are Equal
While many manufacturers offer a range of modified bitumen self-adhered product lines, the product performance varies. When choosing a self-adhering roofing product, contractors, architects, and homeowners should ask the following:
- How well does the product adhere to the substrate
- Can the adhesive withstand contraction and expansion stresses without delaminating, especially from the details, side laps, and end laps
- Does the membrane compress or scuff from foot traffic in hot weather
- How well does the subsequent membrane sheets adhere to the underlying membranes
- How does the product handle when the temperature falls under 40°F
- Does the release film remove effectively during installation of the membrane
Is Cold-Weather Self-Adhered Membrane the Future
The future is here. Cold weather self-adhered membranes are becoming increasingly popular as a roofing option for a variety of reasons. From homeowners looking for a long-lasting roofing system that works well in cold-weather to contractors looking for a roofing solution that is cleaner, cost-effective, and easy to install. Self-adhered membranes are the best choice.
These self-adhering roofing systems have redefined the future of roofing, as they prove to be a cost-effective and safe alternative to traditional roofing methods.
Trust Polyglass for All Your Roofing-Related Needs
When it comes to self-adhered membranes for cold-weather or non cold-weather conditions, Polyglass is a name you can trust. We manufacture high-quality modified bitumen roofing membranes in our state-of-the-art facilities to ensure you save time and money on your next roofing project.
With our multiple patented adhesion technologies, we’ve been innovating advanced roofing solutions for every roofing need.
Polyglass is here to answer all your questions about cold-weather self-adhered roofing membranes. Get in touch with our roofing experts to learn more about our durable self-adhered membranes and other products perfect for your next residential or commercial roofing project.
Contact us to learn more about the best cold-weather self-adhered membranes for your next new or re-roofing project. Explore our range of modified bitumen membrane products for more roofing solutions.