A properly insulated foundation can result in lower heating costs and more comfortable below-grade rooms, if you have any. It can also help prevent moisture problems, insect infestation, and radon infiltration in your home.
In the United States, the most common types of foundations include the following:
* Basements
* Crawl spaces
* Slab-on-grade floors.
Some construction techniques lend themselves to both foundation structure and insulation, including these:
* Insulating concrete forms
* Insulating concrete blocks.
When insulating any type of foundation, it’s also important to take into account moisture control and air sealing.
Source: U.S. Department of Energy, Energy Efficiency and Renewable Energy