Foam Insulation Board Over Windows

Polyisocyanurate is another option coming in as the densest and more expensive option for foam board.

Foam insulation board over windows.

This is an even more dense and more expensive foam board insulation. One common use of extruded polystyrene foam board is for foundation insulation panels. Shop at lowe s to find the foam sheeting you need for your next insulation project. Flash the sheathing around the buck to the window opening with tape or liquid flashing before installing the exterior foam insulation.

It comes in sheets the same size as plywood and is easy to work with. If your building has outie windows you should use the rigid foam or housewrap installed on the exterior side of the rigid foam as your wrb. Instead you should use zip sheathing asphalt felt or housewrap as your wrb. There are basically two types of reflective insulation that can be used by homeowners today.

Typically sold as sheet insulation in a standard size of 4 x 8 foam insulation panels can help reduce energy costs get a handle on moisture control and more. Polyiso comes in several thicknesses and is used over house sheathing underneath siding or in attic spaces where its reflective properties are very effective. It provides an r value of 6 per inch of thickness and often comes foil faced to help reflect radiant heat. Insulating boards are just one of the many types of foam insulation.

Even with all the joints sealed it is still not recommended to have a vertical joint in the sheathing occur over a window head. Prepare a rough opening for a nail fin window over exterior rigid foam insulation. If you choose asphalt felt or housewrap it should be installed between the wall sheathing and the rigid foam. The first is a foam backed foil that is much like the blue foam insulation used on a home s outer shell.

The layout of the sheathing board over the wall area should be done with this in mind.