An important element of spray foam safety is making sure that occupants of a building do not return to the building until it is safe to do so following the spray foam application. Following the correct reoccupancy protocols is essential for preventing chemical exposure, respiratory ailments and other possible side effects of exposure to uncured spray foam. How long should you wait before allowing residents to return to a newly insulated building? This depends on several factors.
One benefit of spray foam is that it cures so quickly. Once it is cured, it does not give off dangerous chemicals, and it is completely safe to be around. However, the exact curing time will depend on the type of spray foam used, how thick of a layer was applied, how ventilated the area is, the outdoor temperature, the humidity, and other factors.
As a general rule of thumb, most product manufacturers recommend waiting at least 24 hours after application is finished to allow re-occupancy. This guideline is based on an interior application of high-pressure spray foam using a 2-component system. High humidity, poor ventilation or a high outdoor temperature may increase the recommended time to 48 hours or longer, so always take these into account before assuming 24 hours is safe.
Visit NCFI's website for more information about spray foam safety and reoccupancy guidelines for our spray foam insulation products.