. EPS Foam Sheets

Article provided by: Star R Foam

EPS Foam Sheets

Foam board insulation is easy to cut and manipulate when you use the right tools. Effective installation of insulation will keep your home safe and comfortable all through the year. 

The fundamentals of installing EPS foam sheets is that the board insulation should face away from direct sun to prevent degradation of the R-value. Cover the insulation before installation to improve the absorption of water vapor and use tape or caulk to maximize insulation between the board or floor and the material. 

The US Department of Energy states that one inch of polyurethane foam will give an R-Value between 5.5 and 6.5. This value is higher than the R-value of fiberglass and guarantees more advantages. Follow the following installation tips to improve the foam’s performance. 

Process of installing gel foam in unfinished walls

Begin by measuring the width and height of the spaces within the walls using studs. Cut the foam insulation to fit the measurements using a box cutter, circular saw, or table saw. These tools save time because they can make substantial cuts with minimal motions of cuts. 

Press the EPS foam sheets into the wall so that they maintain contact with the attachment of studs. Seal the perimeter with caulk after expanding the foam to occupy every space around the border. Sealing the edge maximizes heat efficiency and ensures that the board stays in place long after its installation.

Installation on masonry walls

Foam insulation is applicable on masonry surfaces like block, brick, and concrete with minimal attachment agents. You can place the material on the exterior of the surfaces and then cover them with siding or install them on the interior. 

Cut the foam to fit the surface of the application and cover the back with a construction adhesive. Draw a line of adhesives around the perimeter of the sheet and mark the area at the center. Press the glue to the side of the sheet against the surface of the masonry and smooth it out until it fits into place. Seal the joints between the sheets if you use multiple sheets in adjacent positions. 

What you should know before installing EPS foam sheets


EPS foam sheets have plenty of advantages and one main drawback. The material is highly flammable and must, therefore, have a decent setup against fire hazards. Covering the surface with at least half an inch of drywall is an excellent way of preventing fire breakouts in areas like the garage and attic. 

Using the foam in outdoor spaces poses additional risks of fires. You can minimize the occurrence by covering the foam with another protective finish. 


Faced EPS foams have construction that contains small gas bubbles. The gas leaks out and causes the eventual reduction of the effectiveness of insulation. The US Department of Energy states that one should use EPS foams when they are faced with plastic or foil.

The materials slow thermal drifts and prevent the escape of gas into the atmosphere. Position the faced side of the material to face the home when you use EPS indoors. The faced side should face outside when you use it in the outdoors.




EPS Foam Sheets
Star R Foam
3220 Avenue F
Arlington TX 76011

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