If warm moist house air.
Exposed foam board insulation.
As already noted a decent thickness of extruded foam insulation may create a pretty good air vapour barrier especially when covered with taped and painted drywall.
Shop at lowe s to find the foam sheeting you need for your next insulation project.
Foam insulation alternatives to solid foam board insulation.
Xps has an r value of 4 5 to 5 0 per inch of thickness.
For new construction use rigid boards to insulate slabs and the outside of foundation walls.
Owens corning foamular 250 extruded polystyrene xps rigid foam insulation is a closed cell highly moisture resistant rigid foam board well suited to meet the needs for a wide variety of residential and commercial construction applications.
For a basement remodeling project consider insulating basement walls with foam board.
The problem with that application has always been that the foam board needed to be covered with a thermal barrier or flame spread barrier like drywall in order to meet local fire codes.
Extruded polystyrene foam xps also known as blue board or pink board comes in many different thicknesses and edge profiles.
As far as i know most types of rigid foam insulation can t be left exposed but need to be covered with a layer of drywall for fire resistance.
While many modern foam insulating products do not themselves readily support combustion that is they don t catch fire and burn alone they may give off thick acrid or toxic black smoke in a fire making it difficult to safely exit the burning building.
Compare click to add item r 3 expanded polystyrene foam board insulation 3 4 x 14 1 2 x 48 6 pk to the compare list.
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.
Use a premade kit for this type of project.
Attach the tongue and groove insulation boards to the concrete wall with adhesive.
Foamular 250 product data sheet pdf v 1593673075000 1 45 mb.
Polyisocyanurate is another option coming in as the densest and more expensive option for foam board.
Those are all viable options but perhaps the most sought after option is to insulate with foam board on the inside of the foundation wall so you don t have to worry about the above grade exposure.