DiversiFoam D4 Contour Drop-In Foam BackerBoard
Insulation Board

BackerBoard is manufactured from RayLite brand polystyrene insulation. RayLite is a superior quality insulation that is extremely lightweight. It resists water absorption, will not mold, rot or decay, and will not create a second moisture barrier.

RayLite BackerBoard cuts easily with a knife or can be scored and snapped over a sharp edge.

RayLite BackerBoard's high compressive strength and R-value of 3.85 per inch at 75 degrees Fahrenheit make it an excellent siding underlayment and insulator.

Note that like many construction materials, EPS is combustible. It should not be exposed to flame or other ignition sources. Current model building code requirements should be met for adequate protection or separation from occupied areas.

  • Standard contour double 4 siding backer board packaged (2) squares per box (200 sq ft)
  • Will not shift or vibrate in place when properly installed
  • Increases impact resistance for siding
  • Reduces accumulation of wind-driven dirt and streaking
  • Improves look of siding with less lap exposure and truer profiles