This spray polyurethane foam (SPF) roof was installed over 10 years ago. On average, most of these roof types have 1-2 inches of foam applied onto an existing substrate and are then top coated with an acrylic or silicone coating. To avoid degradation, SPF roofs must be recoated about every 10 years.
First, the roof was pressure washed with 1,500-2,000 psi of pressure. Heavy pressure washing was avoided to prevent damaging the existing SPF system. To aid the cleaning process, a detergent was used to eliminate any heavy residue from the roof surface.
The next step was to cut out and repair any damaged portions of the existing foam to avoid moisture contamination in the new system. Some smaller blisters were patched using polyester fabric and waterproofing mastic.
Once repairs were done, a bonding primer was applied to ensure the silicone top coat would adhere to the existing system. Finally, a silicone base coat and top coat were applied to form a protective, bright-white finish for the foam membrane.