We are often asked what kind of foundation is best.
From many years of experience, here are a few of our thoughts.
Full Height Basement
Advantages: good access to mechanical and electrical systems, adequate
space for appliances and equipment, extra storage space.
Disadvantages: vulnerable to water leakage, not well suited to
some soil types, typically most expensive to build.
Crawl Space (minimum eighteen inches deep)
Advantages: good to fair access to mechanical and electrical systems.
Disadvantages: vulnerable to water leakage, not well suited to
some soil types, moderately expensive to build.
Slab-On-Grade
Advantages: least expensive to build.
Disadvantages: no access to mechanical land electrical systems,
more difficult to heat, less comfortable floor surface.
Cast In Place Concrete
Advantages: most durable, most water tight, strongest.
Disadvantages: more expensive in some geographic areas.
Concrete masonry units (CMU or concrete block):
Advantages: less expensive in some geographic areas.
Disadvantages: less durable, less water tight, more vulnerable
to movement.
Wood (PWF or Permanent Wood Foundation)
Advantages: less expensive in some geographical areas, can be built
in any weather, more flexible for interior finishes, water tight
if constructed properly.
Disadvantages: general acceptance is low, vulnerable to water leakage
if not constructed properly, vulnerable to movement.
Summary
Soil conditions and budgets permitting, most experts agree that
the best foundation is built of cast in place walls enclosing a crawl
space or basement.
This provides access to the mechanical and electrical systems,
good durability and optimum structural integrity. Of course, any
foundation is only as good as the soil it rests on.
Properly designed footings, caissons, piles or other supports are
always important. No home should be built without a thorough analysis
of the underlying soils. From the expansive clays of the Southwest
to the glacial clays of the Northeast, if improperly accommodated,
any soil can cripple even the best foundation.