Commercial Roofing
Climb a corrugated or ribbed metal roof on a hot afternoon and the story is in the screw heads. Some sit proud of the panel, some are ringed with orange, and a few turn freely under a fingertip. Water gets in through those holes long before the panel itself gives out, which is why a metal building can leak for years while the metal still looks decent from the lot.
In Edinburg, TX the panels bake through a long summer and take hard tropical rain, so the fasteners and laps work harder than almost any other part of the roof. Our work on exposed-fastener roofs splits two ways: restore the panels, or, when the metal is spent, build a new standing seam roof over them and skip the tear-off. The first job is to learn how far the failure runs and whether the steel under the screws is still sound.
Each screw passes through a panel rib or flat and clamps a rubber washer against it. Daily expansion and contraction rocks the screw in its hole until it stops gripping the purlin. Sun hardens the washer and cracks it, and rain runs down the shank into the building. Screws set too tight crush the washer on day one, and screws set too loose never seal.
Most of the loosening happens during the Valley's heat-safety months, May to October. We test fasteners by hand and by driver, mark the loose and rusted ones on a roof plan and look at where they cluster. Failures concentrated at panel ends, ridge lines or one slope point to movement or sun exposure, while scattered failures point to age, and each calls for a different repair.
With sound panels, the work starts at the ridge and moves down. Loose screws are replaced with larger-diameter ones and fresh washers set to the right depth, laps get butyl tape or compatible sealant, and ridge caps, rake trim and curb flashing are cleaned and resealed. Rust is brushed back to bright metal and primed the same day, because bare steel flashes over again in humid air within hours. Working downslope keeps loosened debris falling toward the eave, and the trim is finished last.
Restoration has a ceiling. If rust has eaten through a panel, if panels have buckled, or if purlins have corroded, new sealant only postpones the problem. We press on suspect panels, look at the framing from below where access allows and tell the owner which fixes should last and which are temporary. Even a good restoration benefits from a yearly walk, which belongs in a preventive maintenance visit.
A liquid coating over clean, primed metal seals heads and small seams in one pass and brightens the roof, which counts for a lot under Valley sun. Silicone and acrylic are the usual options and they grip metal differently. Either one needs the rust removed, the chalk washed off and the panels dry.
A film cannot stop motion. Laps that flex and screws that back out will crack it, so fasteners are replaced and laps taped first, then fabric is bedded at seams and penetrations. Rain on uncured coating washes it away, and hurricane readiness runs from June through October, so coating is scheduled around the forecast and wet-film thickness is measured at several points on each run.
When the old panels are finished, a retrofit avoids tear-off. Sub-framing is fastened across the old roof and new standing seam panels go on top. The old roof stays as a ceiling and vapor layer, the interior stays dry and occupied, and no part of the building sits open during the work.
The method has limits. The structure must carry the added load, the old roof must be firm enough to hold the new framing, and the cavity between old and new can take insulation. The new roof is specified for the wind loads the building requires, which matters in a county that has seen 50-to-70-mph Hurricane Dolly gusts. We inspect framing and old panels to confirm feasibility and price the retrofit beside a full replacement.
Uninsulated metal buildings sweat. Warm, wet morning air meets a cool panel and runs down the underside as water, with no rain involved. Owners often call it a leak. The roof was never open, and a screw replacement will not stop it.
We sort the two before pricing. Drips that follow rain and line up with screws or laps are roof leaks. Drips that show on humid mornings without rain suggest condensation, and the answer lies in added insulation, a vapor barrier or air movement through the cavity, all of which a retrofit can include. Once Hanna's July 2020 wind and flooding had passed through Edinburg, post-storm checks of edges and flashings were the advice, and on metal that means end laps, ridge cap and gutter transitions. Photographs tie each stain to its cause, and the estimate prices the leak repair and the condensation fix as separate lines.
Gutters and eave closures deserve a look in the same pass. A gutter that sags holds water against the panel edge, closure strips that have crumbled let wind-driven rain in under the first rib, and a ridge cap with open ends admits storm rain along its whole length. Those items cost little to fix alongside the fasteners and cost a lot to rediscover after the next tropical system, so they go on the same work order, each with its own photographs and a note of the condition found.
TxDOT lists a four-lane divided widening of FM 492 from FM 1924 to FM 2221 under Palmview, with another FM 492 route project from US 83 to FM 2221, and the Census Bureau places the Doffing area about 14.6 straight-line miles from Edinburg. Another TxDOT project widens FM 491 in the La Villa area, about 14.1 miles away. Commercial buildings along corridors like these can be clad in metal, though what a building is used for says little about what covers it, so each one starts with a look at the panels.
We serve owners in the FM 492 Doffing corridor, the FM 491 La Villa corridor and Edinburg. Restore, coat or retrofit is settled by three things: panel condition, framing and the owner's time horizon for the building.
On sound panels it is only the first step. Laps and trim also need tape or sealant, otherwise the leak moves a few feet down the roof.
That follows the panel condition, the framing and the exposure. We say what the work should achieve and which pieces are unlikely to hold.
Frequently, since the old roof stays and the building stays in use. The added framing and new panels still cost money, and the structure must carry the added weight.
A little. The roofline rises by the depth of the new framing, and the ribs read cleaner than the old fastener-studded profile.
Sealing cannot hold on perforated metal, so that area has to be replaced or covered by a retrofit. Walking the top and inspecting the underside shows how far it spreads.