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Build on a pier foundation when conditions suit

Tags: Kitchen or bath addition, New construction, Gable or eave end add-on, Tuck under, Foundation, Piers, cold, dry, Foundation and Load-Bearing Elements, hot_humid, marine, mixed_humid

A pier foundation–an elevated foundation on columns–allows construction on difficult sites.
These include swamps, lakes, and areas prone to flooding or hurricane-driven ocean waves. Pier foundations work well on difficult slopes or areas with exposed ledge. And, because of their much smaller footprint, pier foundations have the least impact on the earth beneath the building. Tree roots are relatively unaffected by them. Drainage and runoff are not usually a problem in thickly wooded areas.

Sealing and insulating the bottom of the building envelopeExterior components of a house that provide protection from colder (and warmer) outdoor temperatures and precipitation; includes the house foundation, framed exterior walls, roof or ceiling, and insulation, and air sealing materials. for thermal and moisture protection is more difficult with pier foundations. Careful planning is essential. This is also true for routing underground utilities into the building. In colder climates, water supply and sewer lines need frost protection. Pier foundations in high-risk earthquake zones are not advised.

GREEN POINTS

LEED for HomesLeadership in Energy and Environmental Design. LEED for Homes is the residential green building program from the United States Green Building Council (USGBC). While this program is primarily designed for and applicable to new home projects, major gut rehabs can qualify. :1/2 point available under MR2.2 (Material & Resources) for fly ashFine particulates consisting primarily of silica, alumina, and iron that are collected from flue gases during coal combustion. Flyash is employed as a substitute for some of the portland cement used in the making of concrete, producing a denser, stronger, and slower-setting material while eliminating a portion of the energy-intensive cement required. More info or slag as replacement for 30% or more of Portland cement in foundation.

NGBSNational Green Building Standard Based on the NAHB Model Green Home Building Guidelines and passed through ANSI. This standard can be applied to both new homes, remodeling projects, and additions. /ICC-700:Under Ch. 6 — Resource Efficiency: 3 pts. for using a pier foundation system (601.8); up to 4 pts. for substituting recycled-content, such as fly ash or slag, for Portland cement in concrete (604.1).