Basement foundations should be insulated to minimize energy losses and should be protected from water infiltration. Even if a basement is not intended to be used as a finished space, it’s best to assume that it may be finished in the future. That’s why it’s a good investment to upgrade from damp-proofing to a true waterproofing system when the basement is built. It’s always cheaper to perform this work at the time of construction than years later, when landscaping is in place and excavation is difficult.
For information on ways to improve a damp basement, see Fixing a Wet Basement.
#Types of basement foundations
Full foundations that create usable basements can be built in a number of ways: formed-in-place concrete walls or concrete block on footings are the most common. Insulated concrete forms (ICFs) and precast concrete panels are two newer options. Although it’s possible to build basement walls with treated wood lumber on footings of compacted gravel, all-wood foundations are rarely installed.
Insulated concrete forms
The most common type of ICF is made from inner and outer layers of rigid foam insulation with internal cavities that are reinforced with steel and filled with concrete. The forms are light, easy to handle, and quick to assemble. The foam provides an efficient thermal barrier. ICFs can be used to build above-grade walls as well as basements. ICFs can also be made from recycled polystyrene or wood chips combined with cement.
Treated Wood. Foundations made from treated lumber can be less expensive than building with concrete or concrete block. Despite their novelty among many builders, these foundations have a long history of reliability. Regular carpentry crews can erect them, and wood foundation walls can be set on a gravel base rather than a concrete footing. All of…
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