Roof Coatings

Never Coat Over Wet Insulation

A restoration coating can add years to a commercial roof for a fraction of replacement cost. It is also the most abused product in commercial roofing, because it is easy to spray over a failing roof and walk away.

If the insulation under your membrane is saturated, a coating seals the water in. It cannot evaporate, it keeps degrading the deck, and it will corrode a metal deck from above while the roof looks new from the parking lot. Core cuts and moisture scanning are the only way to know. Anyone proposing a coating without cutting cores is proposing to hide your problem.

When It Is The Right Call

• Insulation dry, confirmed by cores
• Membrane weathered but intact
• Details and terminations sound or rebuilt as part of the scope
• Drainage working, or corrected in the same project
• You need to defer a capital replacement for a defensible number of years

Coating Types

For DFW roofs with any ponding tendency, silicone is usually right. Mil thickness is where cheap coating jobs cut corners: applied at half the specified thickness it fails in a fraction of the warranty period, and you cannot see the difference from the ground. We check with a wet mil gauge.

Coating Salesmen Follow The Storms

After a hail event moves across the Metroplex, property managers start getting calls about roof coatings from companies nobody has heard of. The pitch is quick and cheap, the crew sprays for two days, and the paperwork is a warranty from an entity that will not exist when you need it. Texas does not license roofing contractors at the state level, so there is no board to call about it afterward.

Coating is where this does the most damage, because a fresh white roof looks finished from the parking lot whether or not the assembly under it was dry. Before you sign anything, ask for the core cut photographs and the moisture scan, the manufacturer's name and whether the crew is approved by them, the specified mil thickness with the wet mil readings taken during application, and a local address. Any coating proposal that arrives before someone cut a core came from a sales route, not a roof.