Commercial Roofing
Peeling coating curling off a roof like sunburned skin, with bare patches near the drains and a pale chalk on everything else, is what an acrylic job looks like when it was put on the wrong roof. The same product on a well-drained, dry roof reads very differently: a clean white surface that keeps rooftop heat down and extends the life of the membrane underneath.
In Edinburg, TX the difference comes down to water. With May to October designated heat-safety season, a reflective coat has real work to do, and with hurricane readiness running June to October, a coat that cannot handle water sitting on it has a short future. We look at where the water goes before we talk about the coating.
Acrylic is a water-borne polymer. It goes on wet, loses its water to the air and leaves a rubbery film. Crews can brush, roll or spray it, tools rinse with a hose, and the same material can be thickened with fabric to bridge a crack or thinned for a first coat. It is bright white when new, which sends a large share of sunlight back up, and it bonds to many surfaces: aged single-ply sheets, modified bitumen, built-up roofs, metal and sprayed foam.
Owners pick it for three reasons. It cools the roof surface, it seals pinholes and hairline cracks, and the next coat sticks to the last one, so upkeep means a wash and a thin recoat instead of another full project. Those traits make it a regular part of any roof coating restoration plan where the roof beneath is still doing its job.
Any roof where water lingers. Acrylic that stays wet for days softens, blisters, and eventually lets go of the surface under it, and the damage starts in the low spots and spreads outward. If the roof holds water after a storm, the choices are a drainage correction, a silicone coating, which tolerates ponding, or both.
The best time to read a roof for this is a day after real rain. Hanna's July 2020 flooding in Edinburg shows what a heavy event can do, and flood preparedness is a year-round matter. Dirt rings, algae and a line of debris show where water stood, and we photograph them with a tape measure beside each one. Where the roof clears itself within a few hours, acrylic is a sensible candidate.
Acrylic cures by letting go of its water, and a damp, still morning slows that down. Rain before the coat has set will streak it off the roof, and heavy dew leaves a cloudy, poorly bonded skin. Crews therefore watch the forecast closely and divide the roof into sections small enough to finish and protect before the afternoon sky changes.
Washing, patching and priming can happen weeks ahead, so only the coat itself waits for a good day. We mask cars, glass and rooftop intakes before spraying, drop the pressure when a breeze picks up, and stop when humidity climbs. A halted job leaves a visible edge, so each stopping point is chosen at a seam, a curb or a roof break where a lap will not show or fail. We also keep a small reserve of coating and fabric on site, because a surprise soft spot found during washing is much cheaper to treat while the crew is already on the roof.
The coating copies whatever is under it, so surface work decides the result. Pressure washing removes chalk and dirt. Loose or failed flashing is cut back and rebuilt, seams are taped or fabric-reinforced, blisters are opened and repaired, and rust on metal is treated. Metal edges, gutters and counterflashing get refastened first, because a coat stretched over a loose edge cracks the first time wind moves it.
Moisture comes before everything else. A coat over wet insulation seals the water in, and the heat then pushes vapor up through the film as blisters. An infrared moisture survey and a few cores map the wet areas, those areas are replaced, and a small test patch proves the bond before the full roof is touched. The test patch cures for a few days, and we pull it by hand. If it lifts, the roof gets a different primer or a different plan.
Penetrations get their own treatment. Each pipe, vent and curb is cleaned, flashed with fabric where it needs reinforcement and coated in a separate step so the film is thickest where the roof moves most. Drains and scuppers are cleared and tested with water before the coating goes on, which keeps overspray out of the pipe and shows whether the outlet empties as it should.
Thin coating wears out first at the places that move or get walked on. We therefore specify a number of coats and a minimum wet-film thickness, check it with a gauge at marked points and record the readings. Seams, edges, curbs and drains get extra material, since those spots fail before the open field does.
Whiteness fades as dust, pollen and algae settle, and a yearly wash recovers much of it. A coating also does not replace insulation: where a roof is replaced or substantially rebuilt, the 2018 IBC and IECC that Edinburg adopted govern what the permit requires, and we confirm that with the permitting office. Product, application date and gauge readings go into the roof file, so whoever owns the building next can find them.
TxDOT identifies a divided widening project on Main Street between US 83 and Business 83 in Donna, and the MPO lists Mile 6 North widening work spanning Weslaco and Mercedes. Elsa's economic development corporation describes local commerce serving retail, entertainment and nearby ranching communities. For owners of shops and commercial buildings in towns like these, the live question is whether a sound roof can be restored or must be replaced.
We work in Donna, Mercedes, Elsa and Edinburg, and for each building we line up acrylic against a replacement and against the other coatings. Which one wins is a function of drainage, moisture readings and the number of years the owner plans to keep the property, and we put all three in writing.
Often, since the material and the recoat cost less. On a roof that ponds, though, it is the wrong purchase: a coat that fails in two summers gets paid for twice.
Not until the film has dried through, which varies with temperature, humidity and thickness. We book settled weather and pull the crew when a front shows up on the radar.
Yes, once it is washed and inspected. New acrylic bonds to sound old acrylic, so upkeep is a wash, a look at every seam and a thin recoat.
We time how long the water stays and test whether the drains can be improved. A roof with permanent ponds is better served by silicone, a drainage fix or both.
It seals small, reinforced defects. Open seams, torn flashing and soaked insulation get repaired first, because the film cannot hold back water that is already under it.