Commercial Roofing
Look across a flat roof the morning after a storm and you can read its drainage: bright patches where it dried, dark ones where water is still hiding in a dip. A roof that keeps some water for a day is a poor fit for many coatings and a good fit for silicone, which is the one product in this family built to sit wet without dissolving.
In Edinburg, TX, tropical rain can leave a roof wet for hours and the summer sun is strong for months, so a coating has to take both. We use silicone on membranes and metal that qualify, and we turn down roofs that do not, because a coat applied over wet insulation or a poor bond fails no matter how good the chemistry is.
Silicone sets by pulling moisture from the air, and the cured film shrugs off immersion. Acrylic film, by contrast, can swell and let go under prolonged standing water. That difference matters on older flat roofs where decks have sagged slightly, drains sit a little high or small ponds stay after every storm.
It does not excuse bad drainage. A pond adds weight, gathers dirt and grows algae, and it may mean a drain needs resetting. Street flooding from Hanna in July 2020 is a reminder of how much water Edinburg roofs can be asked to hold. We survey the low spots with a level, open the drains, and add a drain or a taper where we can, using the coating to manage what water remains. The ponding water repair comes first.
Two tests come before any material is mixed. The first is moisture: an infrared moisture survey and a few cores show whether the insulation under the surface is dry. A coat over wet board traps the water, blisters in the heat and wastes the money. Wet areas are cut out and replaced with new insulation, and the cut lines are photographed so the owner can see the extent.
The second is adhesion. We wash the roof, remove loose material and treat rust, then coat a small test area and let it cure a few days before pulling it by hand. Old coatings of another type often need a primer or reject silicone altogether, and the test shows which. After that, seams, penetrations and fasteners get fabric and extra material, and edges and drains are cleaned and detailed by hand before the broad pass starts.
Humidity helps silicone cure, and heat speeds it up, so the Valley climate suits the chemistry. The risk is rain landing on film that has not yet set, which can wash it off the roof. Tropical storms can arrive from June into October, so we plan the year around that window: larger projects in drier stretches, sections sized to finish before an afternoon storm, and priming and sealing done earlier to shorten the coating day.
We spray or roll one or two coats, measure wet-film thickness with a gauge at marked points and write down the readings. Edges and penetrations get checked more often than the field, because thin spots there fail first. The next morning we walk the roof for pinholes and thin edges and touch them up while the crew and the material are still on site.
Detail work takes longer than the open field and decides how the roof ages. Each pipe boot, curb corner, drain bowl and wall base gets fabric bedded in wet coating, then a finish coat that overlaps the fabric by a wide margin. Metal edges are secured first, since a loose edge flexes in wind and cracks the film along its line. Skylight curbs and hatch lids get the same treatment, and the finished detail photographs go into the roof record beside the thickness readings. If a detail looks thin on the walk-through, it is recoated before the crew leaves, not logged for later, and the owner receives the thickness readings along with the photographs.
Dirt sticks to silicone more readily than to most coatings, and a white roof can dull within a few seasons. Rain removes some of it, and a periodic wash brings back much of the reflectivity. Algae shows up first where a pond lingers, as a green or black stain that a wash and a mild cleaner remove, and its position makes a useful map of where water still stands after a storm. When wet the film is slick, so walk routes need traction pads and service staff should know.
The bigger limit is what comes later. Little bonds well to cured silicone, and even a fresh silicone coat needs a prepared surface. Owners who may switch to another coating or a new membrane should know that the silicone must then be removed or covered with a compatible product. We log the product, date and thickness in the roof record, and an annual look at wear fits into a preventive maintenance visit.
The best candidate has a sound membrane or metal panel, dry insulation, and problems limited to surface wear, small leaks and heat. TPO and PVC single-plies, aged modified bitumen, smooth built-up roofs, metal and sprayed foam can all take it when prepared well. Roofs with widespread wet insulation, rotted decking or a membrane that has bubbled away from its base cannot.
The decision is partly financial. Compared with replacement, a coating spares the owner the removal and disposal, yet it can only last as long as the roof under it allows. The roof coating restoration process opens with the condition and moisture findings, and the recommendation that follows may well be a repair or a replacement instead. Edinburg's adopted 2018 IECC applies where insulation changes, and we check it there.
The MPO lists a Westgate Business 83 widening project and other Weslaco work on Airport Drive and Border Avenue, and TxDOT lists Military Highway construction from Shary Road to Abram Avenue in Mission. Where a corridor is being improved, an owner may want to hold a sound roof through the work, and a coating can extend it through that period without a full tear-off. Road projects tell us nothing about any particular roof, so each building starts with a walk.
We serve owners in the Westgate Business 83 corridor in Weslaco, the Shary Road corridor in Mission and Edinburg, and we weigh silicone against an acrylic coating using the roof's ponding, the budget and the plan for the building.
Only a sound, dry roof with a surface it can bond to. We scan for moisture and cure a test patch before committing to the whole roof.
Where water ponds, yes. Where drainage is good, acrylic can cost less and recoat more easily.
When wet, yes. Traction pads go along access routes, and service crews get a warning.
That depends on the product, humidity and temperature. We book dry spells and stage the work in sections so a storm never catches an uncured area.
Small defects that have been reinforced, yes. Large splits, soaked insulation and failed flashing get fixed before any film goes down.