Features of Precast Concrete Foundation Walls
While most concrete contractors would prefer to cast concrete foundation walls in place, precast concrete foundation walls have some attributes that make this technique appealing to modular home owners and builders. For concrete contractors, either erecting or actually casting precast concrete foundation panels could be a lucrative addition to what you can offer your customers.
Precast Concrete Foundation Has High Insulation Rate
The most popular precast concrete foundation walls come as nearly finished panels, incorporating insulation and interior studs ready to accept drywall. On site, precast panels go up much more quickly than cast walls, including those constructed with insulating concrete forms (ICF). And since there’s no concrete placed on site, construction can proceed in virtually any weather without concern about freezing or wet conditions. Precast concrete foundation wall erection is also simpler than cast-in-place or ICF construction and can be done by low-skilled workers with only one trained lead.
Insulated panels come in various configurations, depending on the owner’s requirements. The exterior face of the monolithic panel is 2-inch-thick concrete with integral 6 ¾-inch-deep concrete studs and reinforced bond beams, top and bottom. Standard wall panels have an insulation value of R-5 from 1 inch of rigid insulation attached to the concrete between the studs. Thicker insulation can increase that to R-21.
Precast Concrete Foundation is Crack Free and Waterproof
This precast concrete system results in crack-free and waterproof walls. The panels are made with 5000-psi concrete with low permeability. Since the concrete is cast in a factory setting, all shrinkage has taken place prior to erection of the walls so panels virtually never crack in service. A broom finish is standard for the exterior of the panels, although other finishes are available, including simulated brick or flagstone textures.
Precast Concrete Foundation Has No Footer
The base for precast concrete foundation panels is crushed, compacted gravel—no footing is poured. After excavation, 4 inches of ½-inch crushed stone is placed and compacted with a drainage system beneath. This base is adequate for most soils and loading conditions.
Precast Concrete Foundation is Above Grade
Precasters also provide panels for above-grade walls. The Thermomass system is a sandwich panel that has interior and exterior concrete wythes with a rigid insulation interior, all attached with fiber-composite connectors.
Manufacturers of precast concrete produces what they call double-wall panels intended to be used for an entire modular home like the walls, floors, and even roof deck. Interior and exterior 2 3/8-inch-thick concrete wythes are cast, held together by wire trusses. Rough electrical and plumbing are installed in the cavity and the void is filled with foam insulation. Precast concrete foundation panels are connected with an infill of high-strength grout. They claim that a medium-sized modular home can be erected in about five days, although that is preceded by several weeks of planning.
Superior Walls’ above-grade panels are virtually the same as the foundation wall panels. They have been used to construct up to three-story structures (a foundation wall and two levels above grade). Panels can be designed for any architectural feature desired.
In case you still have question about modular homes, you may contact Legendary Homes Inc in Jackson, Michigan. A representative will be happy to assist you. Meanwhile you can check our modular home price sheets by signing up to our blog
Topic: Precast Concrete Foundation