If you’ve decided to use foam board insulation for your construction project’s exterior walls, you’ll also need an accessory to go with it: tape for the joints.
When putting together your building’s enclosure, your system is only as good as its weakest point. That’s what makes sealing the joints between rigid insulation boards so critical. This step keeps air and other elements from seeping through the cracks and into your building’s interior by performing as an air and vapor barrier.
There are many construction tapes on the market to pick from. Choosing the right one for your job ensures that your building’s wall systems can perform as intended.
Learn more about the best tape for foam board insulation for your exterior wall applications below.
The Difference Between Construction Tape and Insulation Joint Tape
When shopping for the best tape for foam board insulation applications, you’ll need to choose between construction tape and insulation joint tape. Both types of tape are made of an adhesive and a backing material. The difference between construction tape and insulation joint tapes is in the material used for these two components.
Construction tapes are more versatile and can be used for multiple applications outside of just sealing insulation joints, including sealing windows and other penetrations. They can be made of rubberized asphalt, butyl, or acrylic. However, not all construction tapes can double as insulation joint tapes, so you’ll need to verify compatibility with your installation.
Insulation joint tapes are designed specifically and solely for sealing insulation joints for corresponding types of insulations and facers. This type of joint tape is usually made of an acrylic adhesive and features various backing materials—including foil, foam, paper, or BOPP film.
What Is the Best Tape for Foam Board Insulation?
To get the best of both worlds, look for an acrylic-based construction tape that is compatible with your insulation. Acrylic is an ideal adhesive for walls due to its properties of water and mold resistance, as well as adaptability to temperature changes. Other factors to consider when shopping for the best tape for foam board insulation include the following:
Pressure-sensitive
Water-resistant
Mold-resistant
Moisture-resistant
Wide enough to cover the joint
Tough, durable
Compatible installation temperature range
Wide operable temperature range
Rmax R-SEAL Construction Tape
Rmax R-SEAL Construction Tape is specifically designed for use with aluminum-faced polyiso products, including Rmax Thermasheath®-SI and Thermasheath® insulation. It can be used for additional applications such as sealing around windows and door frames, patching, and more. The tape is 3” wide and comes in a 165-foot roll.
The 3 mil acrylic-based tape is pressure sensitive for maximum adhesion. Additional reasons that Rmax R-SEAL is the best tape for foam board insulation include UV-resistance and weather-tight seal. This tough sealing tape can be installed at extreme temperatures from five below up to 180 degrees Fahrenheit and it is also effective in sub-zero temperatures as low as -40 degrees.
How to Apply Rmax R-SEAL Construction Tape
To install Rmax R-SEAL—first, verify compatibility by testing the adhesion on your material (skip this step for Thermasheath® and Thermasheath®-SI). Once you’ve confirmed compatibility, proceed with these steps:
1. Clean any dirt, dust, moisture, or other debris off your insulation with a dry cloth.
2. Center the tape over the joint or object that you’re taping (extend ¾” beyond the joint’s edge).
3. Affix the tape so that it is smooth and flat.
4. Cut the tape from the roll at the end of the joint with a utility knife.
5. Flatten out any imperfections with a feathering tool or hand roller.
Rmax R-SEAL 3000 as Adhesive for Insulation Joints
If you’re looking for a foil-backed joint tape, Rmax R-SEAL 3000 is a construction tape that has superior conformability for taping foam board insulation joints. This 2 mil acrylic-based pressure-sensitive tape features foil coating plus a release liner for maximum adhesion even in cold conditions. This tape is 4” wide and comes in a 150-foot roll.
How to Apply Rmax R-SEAL 3000 Tape
R-SEAL 3000 Tape is installed the same over insulation joints as standard R-SEAL. Clean the surface, tape the joint, and apply pressure for a good bond. Lastly, smooth out any wrinkles with a feathering tool.
Key Points of Using a Good Quality Tape for Foam Board Insulation
You’ll know you’ve got the best tape for foam board insulation when your construction tape has these attributes:
Excellent adhesion
Easy to work with
Easily cuttable in the field
Flexible
Durable
Long-lasting
Adequate coverage
Rmax is the Superior Construction Tape for Insulation Joints
As an industry leader in insulation products since 1978, Rmax stays on top to bring better products and accessories to builders as technology and codes change. Check out our full line of accessories which includes tapes, clips, and anchors. We help your projects run smoothly by providing solutions that make the job easier.
If you need expertise in matching the right product to your project, contact your local Rmax representative today.