Foundation walls are the same basic principal as retaining walls. Foundation walls are set up and poured the same way. Foundation walls are notorious for letting moisture from the ground seep in through the mortar joints, block or even concrete. Even in new construction concrete foundation walls take several months to cure properly.
Poured concrete and masonry block are the most common materials in new construction. Poured concrete foundation walls provide the structural integrity necessary to bridge “soft” zones on “marginal lands,” saving the builder and consumer time and money when construction takes place on fill or poor soil conditions. And technological advances in concrete mixtures provide quality control for poured concrete foundation walls constructed in inclement weather or freezing temperatures.
Footers (the things your foundation sits on) may be built on loose material. It might expand or contract over time because of the weight on it, or you may be in an area with soils that move. Footings are the widened portion at the foot of the foundation walls. They must be placed below the frost line to prevent the building from moving as the ground expands and contracts during freeze/thaw cycles.
Foundation walls are surprisingly complicated things because they have to hold up the weight of the house, resist the pressure from the ground surrounding them, and keep the basement dry and warm. That’s why building codes are so strict about them, and that’s why they require so much painstaking planning. Foundation walls are constructed by pouring concrete between sets of form work. Wall thickness is determined by a structural engineer who considers the height of the wall and the load it has to bear. Foundation walls are typically load-bearing, lumber-framed walls sheathed with structural plywood panels. All lumber and plywood components in a PWF are pressure treated with a relatively high concentration of a waterborne preservative to withstand decay from moisture and insect damage.
Foundation walls are poured concrete, concrete block or wood. The major factors determining the size and shape of the footing are the weight of the structure and the bearing capacity and stability of the soil. Foundation walls are built on the footings. They are most commonly made of poured concrete or concrete block. Foundation walls are set and poured on day two. On day three, the forms are stripped. If you choose to do your walls out of block it could possibly save you time but it is considerably more work and time consuming. Poured concrete walls can have special designs such as Brick, stone or many other designs. This will give your basement a different look when you finish it off.
Concrete is designed based on the strength it should attain in 28 days, but it takes time to reach that strength, and the concrete can be vulnerable during that period. Tensile force is applied to concrete as it contracts due to the evaporation of unused water. Concrete professionals know that unless the material used fills the crack cavity completely, including the portion of the crack below the floor, it can’t be considered a permanent repair solution. The only material capable of completely penetrating a concrete foundation wall crack is epoxy. Concrete is tested when it is poured to ensure its structural integrity. Foundation walls are designed to bear the full load of the house.
Usually a basement is not backfilled for at least 10 days after the concrete has been poured and must have bracing material in place before the dozer pushes the heavy dirt into place. A drain tile is also placed around the exterior walls along with pea-stone on top so that any water that accumulates around the walls can be moved away from the house and keep you basement walls dry.
As always just be sure to do your homework when trying to find the best contractor for the job. The lowest price is not always the best way to go and if you choose to make your final decision on just that fact, be prepared to be disappointed most of the time.