Crawl Space Foundations Are Found In Many Homes

If a combustion appliance such as a gas or oil furnace is present, a dedicated combustion air supply may be necessary during the heating season. If outside grade is higher than inside grade, a damp proof coating on the exterior foundation wall is recommended. spraying insecticides and re-insulating ductwork).6. rain water, underground springs) must be eliminated.Conditioned Crawl SpaceThis method is usually used in new construction but can be specified for retrofit applications when existing insulation is damaged and must be removed. The goal of this step is to provide 100% ground coverage and eliminate as much outside air as possible being pulled through the block walls. Cut blocks of ½" to 2" rigid polystyrene and pressure fit into the backside of vent openings to further reduce the intrusion of outdoor air. Access doors are insulated using 2 inches rigid foam board or equivalent. In either case, the band joist is insulated using either rigid or batt insulation. Additionally, high humidity provides an ideal environment for insect growth. Seal the CleanSpace to the foundation wall by using construction adhesive. Batt insulation extends down the wall and terminates 2 to 3 feet into crawlspace with seams continuously taped.4. Research and experience has shown that unvented and conditioned crawl spaces provide better moisture control than vented crawl spaces and behave similarly to houses constructed with basements. The durable CleanSpace vapor barrier covers the foundation wall and terminates under the sill plate (or lower if retro fitting). This technique is not in full compliance with local and national building codes and should not be specified for new construction. Extend the outside edge of the CleanSpace up the foundation wall to a few inches below the top plate. Downspouts should empty 8 to 10 feet from the foundation2. The code also allows for the installation of an exhaust fan to exhaust crawl space air to the outside.2. Because exhausting can create negative pressure in the crawlspace, this method is not recommended.e. From that point forward, the space should operate safely. Outlined below are techniques for unvented and conditioned crawlspace construction. Outside foundation walls are insulated using code approved rigid insulation with flame spread less than 25.If you have crawl space problems we can help. Install gutters and slope grade away from the foundation at least 5 %( 6 inches per 10 feet) to direct rain and surface water away from the house. Seal forced air ductwork to reduce or eliminate leakage.e. Outdoor air is controlled by sealing all penetrations to the exterior and installing gaskets.