Commercial Roofing
A roof that gets blasted by sun for half the year does not fail in one afternoon. It chalks, then crazes, then shrinks a little at every seam and flashing until a storm finds the weak spot. On a flat roof in Edinburg, TX, the Rio Grande Valley's heat-safety season, which NWS Brownsville places from May into October, is the long stretch of sustained roof-surface heat and solar exposure. I start a heat and UV call by looking at the surface for the first signs of that wear, then follow it down into the details that move the most.
The facility director wants to know what is cosmetic, what is a leak waiting to happen and what a restoration would cost compared with replacement.
On a single-ply sheet, I look for chalking, fine surface cracks, hardened edges and areas where the color has faded unevenly. On a coated roof, the coating can peel, blister or wear thin to the base. On a modified bitumen cap, granules wear off and expose the asphalt to direct sun. Sealants crack and pull away from the surfaces they were meant to join. None of these alone proves a leak, but together they tell me how much service life is left in the surface.
I photograph the worst areas next to the best ones. The contrast shows how fast the roof is aging.
Color tells part of the story and the underside tells the rest. Where a lap has lifted, the underside of the sheet shows whether the weld or bond was sound, and the dirt line along the edge shows how long the opening has been there. I lift a corner of a few suspect laps to check, then close them again and note which ones were already open.
Mostly at the details. The field of the roof can be crazed and still shed water, while a heat-shrunken flashing or a split sealant lets it in. As a sheet shrinks, it pulls on its terminations, lifts off the wall and opens the top edge of the base flashing. Water then runs down behind it. I trace the stain backward along that path and check the flashing at penetrations first, since movement concentrates there.
A moisture survey confirms whether the water has spread beyond the detail.
Shrinkage shows up as tension. A sheet that has drawn back from a wall leaves a small gap at the base, and a membrane that is bridging a corner instead of lying in it is under strain. I press on those spots and look for sheet that sounds hollow. A heat-shrunken detail often looks tight in the morning and open by afternoon, which is another reason I take photographs at different times of day.
I press on the sheet to check flexibility, flex a corner of a patch and watch for cracking, then probe the seams for open edges. A sheet that bends and recovers still has life, while one that snaps or splits at a fold has hardened. I also look for exposed reinforcement, because a scrim showing through the surface lets water wick into the sheet. These checks determine whether the roof can accept a restoration or needs a different repair.
Surface temperature affects the testing, so I note the time of day and avoid judging flexibility at the hottest hour.
I also check the fasteners. Heat and movement back out fasteners in a mechanically attached sheet, and loose plates let the membrane flutter under wind and wear at the seams. Where I find a pattern of loose plates, I report the area and the likely cause, since re-fastening can be cheaper than a larger repair if it is done before the sheet is damaged.
A roof is a candidate for restoration when it is dry underneath, fastened well and structurally sound. A roof coating restoration can renew a weathered surface and add reflectivity, and a silicone coating resists ponding water better than some alternatives. If the insulation is wet or the sheet is hardened through its thickness, a coating only covers the problem. In that case, a recover or replacement is the sound choice, and I show the cost side by side.
The substrate sets the limit on any restoration. A coating needs a clean, dry and stable base that holds fasteners well. I test adhesion on a small area before committing to a full surface, and I report the result. Coating thickness, cure time and the weather window all have to line up, and I describe them in the scope so the facility director sees the conditions for a good result.
Seams and flashings come first, because a coating or patch over an open lap fails with the lap. I repair open seams, rebuild cracked flashings, replace failed sealants and fix punctures, then clean the surface for the new layer. The boundary of each repair runs from sound material to sound material, and the record shows where each one is. A seam failure at the edge of a restored area is the usual reason a restoration disappoints, so the seams get probed twice.
Cool-roof options can lower surface temperatures, and I describe where a cool roof fits the building.
The written scope lists every repair that must come before the coating, with quantities, and every detail that will be coated over. If the building has a failing flashing at a wall, it is rebuilt first, since a coating applied over a moving detail splits with it. The repair order is part of the price.
Heat shortens the working day. Adhesives and coatings cure too quickly in direct sun, and a surface that is too hot to touch will not accept a bond. We begin early, stage materials in shade, watch the surface temperature and stop when conditions leave the window. The work is divided into sections that can be finished in a shift. An owner with several buildings, say along the Mission Shary Road corridor, can compare how each roof has aged by keeping one photo record across them.
Restoration also depends on afternoon storms. In the wet months, sudden rain can wash out an uncured coating, so the crew watches the forecast and closes the day with all coated areas cured or covered. The record logs the weather at each stage, so a later question about a spot of poor cure can be traced to the conditions.
Test the flexibility of the sheet and probe the seams and flashings. A faded or chalky surface that stays flexible and watertight is often cosmetic. Cracks, open laps and exposed reinforcement are not.
It reduces surface temperature, but it does not stop UV or movement at seams and flashings. The deciding factor is the condition of the details, which still need inspection.
No. Coating over trapped moisture seals the problem in. A moisture survey comes first, and wet areas are cut out and replaced before the coating goes on.
At least before the heat-safety season and after any major storm. I recommend photographing the same areas each time so changes show up clearly.
It depends on the terms, which differ by manufacturer. Send the paper and the repair history, and I will read the notice and maintenance requirements.