An exposed floor is any floor that overhangs the exterior wall or is otherwise exposed to exterior conditions. This could be a bay window, a fire place bump out, a floor over a garage, or any floor where the floor below has a thicker wall. Because the floor is exposed to the outdoors or to the garage (which will not be the same temperature as the rest of the house) there will be heat loss through the floor. Properly insulating the exposed floors can significantly reduce heat loss through these areas and help to provide a higher level of occupant comfort.

Insulating exposed floors:

Batts should be cut to fit and placed using the same techniques used in wall cavities. A means of securing the batts in place needs to be incorporated. This is often strapping that is placed on the underside of the joists.

If the underside of the floor is exposed in such a way that it may be subject to mechanical damage, it must be protected in accordance to the Building Code. A friendly reminder to the builder should be all that is required by the insulator.