Your flat roof is showing its age. There are hairline cracks, the surface looks weathered, maybe you have patched a few small leaks. But the membrane underneath is still solid. Full replacement seems like overkill.
Recoating might be the answer. A quality coating can add 10 to 15 years to a flat roof at a fraction of replacement cost. But it only works if the existing roof meets certain conditions.
When Recoating Makes Sense
Recoating works best when your roof has surface deterioration but structural integrity. The membrane should be intact - no large tears, no extensive bubbling, no soft spots where water has gotten underneath.
A roofer evaluating your roof for coating should do core samples. They cut small sections to check the layers underneath. If moisture has penetrated the insulation, coating over it just traps that moisture in place. The roof will continue to fail from inside.
Drainage has to be working. Coating will not fix ponding water problems. If water sits on your roof for days after rain, you need to address that first.
Assuming your roof is a good candidate, here is what the process looks like.
Cleaning comes first. The surface needs to be free of dirt, debris, grease, and any loose material. Pressure washing is typical. The coating will not adhere properly to a dirty surface.
Repairs happen next. Any cracks, open seams, or damaged areas get patched before coating. Flashing gets resealed. The goal is a sound surface that the coating can protect.
Primer goes on if required. Some coatings need primer to bond correctly to certain membrane types. Your contractor will know what your specific roof needs.
The coating itself gets applied in multiple coats. Each coat needs to cure before the next one goes on. This usually means the project takes a few days. The crew applies coating with rollers, brushes, or spray equipment depending on the product and roof conditions.
Thickness matters. A properly applied coating has measurable depth. Cheap jobs that spray a thin layer might look okay initially but will not last.
After coating, the roof needs time to fully cure before foot traffic. Your contractor will specify how long.
Peak Builders evaluates and coats flat roofs throughout San Diego. We will tell you honestly whether coating is right for your roof or whether you need a different approach.
