Insulating Concrete Walls Below Grade

Because they are naturally located below ground level basements are mostly cool and damp.

Insulating concrete walls below grade.

Interior insulation insulated cavities insulation inserts foamed in place insulation granular fills in block core spaces and exterior insulation systems. Because insulation installed on below grade building foundations and under concrete slabs is often exposed to moist soil it is crucial to choose an insulation that has minimal long term moisture retention and the ability to dry quickly. If the foundation is on frost susceptible soils install a layer of impermeable insulation horizontally in the soil at a slope ratio of 1 5 for at least 1 m 3 ft. Installing rigid foam insulation below grade on building foundations the insulation whether eps or xps is installed over the damp waterproofing after that layer has adequately cured.

Preparing masonry block walls for exterior damp proof coating. Any of the following insulation materials are acceptable for this purpose. Above and below grade walls of a building or home can use insulated concrete forms icfs in their construction. Both above and below grade icf walls are durable sound reducing energy efficient and disaster resistant.

For poured concrete walls a damp proof coating can be applied directly to the surface. The best way to insulate the interior side of a basement wall is with foam insulation that is adhered to or sprayed directly on the concrete. However because of soil conditions below grade walls require added waterproofing steps unlike above grade walls. Insulation is applied to houses with slab on grade foundations exactly as you would insulate the outside of a full basement see section 6 1 insulating the basement from the outside.

Wet insulation is ineffective insulation rigid foams that retain high volumes of moisture lose about half of their insulating r value. A properly insulated basement provides comfort and is a good way to save on your energy bill. Insulation on the exterior of below grade portions of the wall is. Basements however have specific features that must be kept in mind when it comes to insulating the foundation from the inside starting with the fact that a variable portion of the walls is below ground.

However for masonry block walls and below grade insulated concrete forms the surfaces must first be prepared. Rigid foam can be adhered to a poured. Closed cell spray polyurethane foam or either xps eps or polyisocyanurate rigid foam.