How to Work with EPDM in Cold Weather

One of the questions most often asked about EPDM roofing is whether or not it can be installed in poor or cold weather conditions. Whilst most other roofing solutions require at least a warm temperature for installation such as GRP roofing, which requires an adequate temperature for the resin to cure properly, EPDM can be installed all year round, even in the cold weather. Some extra precautions and safety measures do need to be taken, which we will outline in this guide.

Precautions Before Installing

• Check the weather forecast for the day you plan to install the EPDM roofing. If temperatures are expected to drop below 5°C within the first 24 hours after installation, the installation should be postponed as freezing temperatures can cause adhesives to not work properly.
• Ensure that the roof space that you are going to be applying the adhesive to and laying the membranes on is dry.
• Take extra care when climbing and navigating the roof in cold weather, especially if there is ice on the roof from the previous day.

1. Membrane Preparation and Installation

• Relaxation Period: Before you begin, you should allow EPDM membranes to relax for at least 30 minutes in their final installation position. This will help reduce tension and ensure that the membrane remains flat during the installation.
• Timing: The membranes should be installed as soon as the adhesive is ready. Water-based adhesives can be applied to the flat roof to begin the installation without any delay, making them ideal for cold weather. PU and bonding adhesives should be tack-tested first to measure their adhesion capabilities. These adhesives can then be evenly applied over the flat roof area and allowed to become tacky before installation.
• Consolidation: Once the membrane is placed on top of the applied adhesive, consolidate the bond using a broom, roller, or squeegee.
• Tape Temperature: Use an electric hot air gun to warm the tape before application. This is especially important in cold conditions as warming the tape improves its flexibility and adhesion.

2. Adhesive Storage and Care

Keep your EPDM adhesives in a warm environment before and during the installation to maintain their effectiveness. Cold adhesives can thicken, which will make them difficult to spread evenly across the roof.

Avoid leaving any canister adhesives outside overnight, as cold temperatures reduce the pressure within the canisters, which makes applying them more difficult. Instead, store them indoors or in an adequately heated area. Cold weather can cause condensation to form on adhesives, particularly HP-250 primer and SPB adhesive. Use a cold air blower to evaporate condensation before bonding surfaces.

3. Pressure-Sensitive Elastoform Products (Uncured Tapes)

• Storage: PSEF products can cure prematurely if they are exposed to heat for an extended period of time, so be sure to store them in a cool and dry place to maximize their shelf life.
• Usage: If you find that your PSEF tape has become stiff from the cold, use an electric heat gun to warm it up, which will make it more pliable and easier to work with.

4. Lap Sealant Application

Lap sealant should be applied along the entire edge of all PSEF products where water might sit or flow in order to add an extra layer of protection against leaks. Use a tool to feather the edges of the sealant to create a smooth and seamless transition that prevents water pooling. We’d recommend that the application of leap sealant be completed on the same day as the PSEF installation, since prompt application minimizes the risk of water ingress.

We hope that this guide has answered any questions you might have about working with EPDM roofing in colder weather, but if not or you would like to learn more about our EPDM products, please don’t hesitate to contact us.