Homes are built on a number of different support systems; the standard well known types on footings are slab, crawlspace, and basements. There are others that deal with particular soils conditions such as piers, grade beams, driven piles and engineered post tension slabs.

1.Your problems with a slab foundation are pretty straight forward. Slab foundations are built in one variation as one pour of concrete including the footing, walls, and floor system. The tendency of single pour solid concrete slabs is to crack because the concrete cures at different rates based on the thickness or mass. The floor system is normally 4 thick and cures at one rate, the walls and footing maybe 12 thick and 30 deep will cure at a different rate this can cause cracks in the floor system. These cracks will cause an opening to the soil below which is the big problem. The crack will cause moisture to wick into your carpet, the crack may split the hardwood floors, crack your ceramic tiles, and stain the vinyl tiles or sheet flooring.

Slab foundations are also built on footing with block or brick walls and floor system. The chance of cracking is less likely to occur with this system. The footing is poured separately cures, the foundation walls are erected and the floor system is poured and cures. The chance of cracking is lessened because of three separate stages of work. The cracks can occur but are at a minimum as compared a single pour system.

2.Crawlspace problems are cause by the poorly finished or unfinished areas below the first floor decking. The dirt floor of a crawlspace can be covered with different materials according to local and state building codes. Some required a concrete slab over a 6 mil plastic vapor barrier others require only 100% coverage of a 6 mil plastic vapor barrier. Both can cause serious moisture problems because of the unfinished walls and unconditioned area of the crawlspace. The unconditioned (no heat or air conditioning) space can cause mold, mildew in the crawlspace and moisture to wick up into the home through the wood joist and deck floor system. This is causes odors in carpet, cupping or warping hardwoods, wet ceramic tiles, and stains in vinyl floor backing.

Worst yet is that in some cases the heating system and the water heater are located in the damp wet crawlspace causing corrosion on the pipes, fittings, valves, and any metal parts in the crawlspace over time it will be a huge problem for any future homeowner. The better builders today are providing a completely conditioned crawlspace where the dirt floor is sealed the walls are sealed and insulated which keeps out the moisture and allows your mechanical systems to operate properly for years. What did your builder do or what are the plans for your new home?

3.Basement problems can be the same as crawlspaces with the unconditioned areas except the basement is deeper in the ground, closer to any water level or water table which can be a more serious problem. Basements have always had the reputation for being damp and smelly they still can be if the builder is not using modern waterproofing materials and designs. The possibility of floor system cracks exists in basement homes. Using proper water proofing techniques and exterior grading basements have become very desirable. The walk-out condition where the rear wall is actually open to ground level (the lot sloping down from front to rear) has offered some excellent opportunities for homeowners to add usable heated square footage to the home and become a much better alternate to the finished bonus room on the third floor.

Your choice of foundation system is governed more by the site and soil conditions. Most builders would rather build what pleases you at a profitable cost than to chance losing a sale. Some homebuilders you may find are stuck or set in their building techniques and may not offer you choices that are evidently available or possible.