Silicone Roof Coating · Houston, Texas
Commercial Roof Coating in Houston: Silicone Restoration
A restoration coating can add years to a sound commercial roof without a tear-off. It can also fail fast on the wrong roof. This page explains how to tell the difference, how silicone compares with acrylic and urethane, and what actually drives the price for buildings across Houston and the Bay Area.
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The short answer
Commercial Roof Coating: what Houston owners should know.
A commercial roof coating is a fluid-applied membrane, such as silicone, acrylic or urethane, sprayed or rolled over an existing roof after cleaning and repairs. It works when the roof is structurally sound and free of wet or damaged insulation. Silicone is often chosen in Houston because GAF's silicone products are built to resist ponding water and stay reflective in strong sun.
Mammoth Services evaluates and installs restoration coatings on commercial roofs in Houston and the Bay Area, starting with a roof assessment that checks for wet insulation, drainage and adhesion before recommending a coating or not. Cost depends on condition, repairs and coating thickness, not a flat rate. Call (832) 416-1566.
Candidate or not
When a roof coating makes sense, and when it does not
GAF says a roof is a restoration candidate when it is structurally sound and free of wet or damaged insulation. Everything starts there.
Good candidates
Roofs with normal aging and wear, intact membranes or panels, and dry insulation. GAF lists metal, aged single-ply, smooth and granulated asphaltic, structural concrete, SPF and previously coated acrylic as substrates its coatings can restore.
- Aged TPO, PVC or EPDM with sound seams
- Modified bitumen and built-up roofs in fair condition
- Metal roofs with surface rust but strong panels
Poor candidates
GAF notes replacement may be needed when damage is widespread or when coatings have previously failed to adhere or perform. Coating over saturated insulation seals the water in.
- Wet or crushed insulation over large areas
- Deck damage or structural concerns
- Previous coating peeling or delaminated
Moisture survey first
Wet insulation is not visible from the surface. Before recommending a coating, we run a moisture survey and confirm readings with core cuts. Wet areas are cut out and replaced so the coating goes over a dry, solid base.
- Infrared or capacitance scan
- Core cuts to verify
- Wet area removal priced separately
Adhesion test
GAF calls an adhesion test essential for any roof receiving a coating. If adhesion fails, a primer may improve it on certain substrates. Newer substrates can be harder to bond to than aged ones.
- Test patches on each substrate
- Primer where results call for it
Sources: GAF, restoring a commercial roof, GAF roof coating systems, GAF, silicone coatings.
Chemistry
Silicone vs acrylic vs urethane roof coatings
Each chemistry has a job. In Houston, rainfall and flat roofs that hold water push many projects toward silicone, but not all.
| Silicone | Acrylic | Urethane | |
|---|---|---|---|
| Strength | Ponding water resistance; moisture resistant; UV stable | Durable, highly reflective white, low-odor options for occupied buildings | Tensile strength, abrasion and chemical resistance |
| Ponding water | GAF says silicone typically has no warranty exclusion for ponding areas | GAF says ponding can be detrimental to acrylic performance | Not addressed in GAF's comparison |
| Watch for | Slick surface; less dirt pickup resistance; may need cleaning to stay reflective | Needs positive drainage | Manufacturers generally do not warrant grease or chemical exposure |
| Fits | Low-slope roofs with ponding, humid climates | Well-drained roofs, metal restoration | Manufacturing and food processing roofs |
Sources: GAF, how to choose the right roof coating, GAF, best use cases for silicone, GAF Technical Bulletin C-47.
Ponding water
Ponding water and silicone in Houston
Flat roofs in Houston see heavy rain. Ponding is one of the main reasons silicone gets specified here.
GAF defines ponding water as water that does not drain or dissipate from the roof surface within 48 hours after precipitation ends. It also notes ponding can come from improperly piped air-conditioning or steam condensate lines, which is common on Houston rooftops.
The warranty language follows the chemistry. GAF's Liquid-Applied Emerald Pledge limited warranty specimen excludes conditions that prevent positive drainage or areas that pond water, but that exclusion does not apply when GAF Unisil or GAF High Solids Silicone is used. GAF's Unisil data sheet states the coating provides protection against leaks due to ponding water, while also listing positive drainage among its application requirements.
For acrylic-coated roofs with poor drainage, GAF's Technical Bulletin C-47 allows Unisil over eligible GAF acrylics in ponding areas, applied within 90 days and extended at least 4 feet beyond any area that ponds. Where possible, GAF still advises fixing ponding first. We look at drains, crickets and condensate lines before choosing a coating, because solving the water is cheaper than coating around it.
Sources: GAF Technical Bulletin C-47, GAF Liquid-Applied Emerald Pledge specimen, GAF Unisil data sheet.
Cool roof
Cool roof benefits in Houston heat
A white coating changes how much heat the roof sends into the building. The data is published; use it.
Lower roof temperature
The U.S. Department of Energy says conventional roofs can reach 150°F or more on a sunny summer afternoon, while a reflective roof under the same conditions could stay more than 50°F cooler.
Biggest payoff in hot climates
DOE notes cool roofs save the most cooling energy in hot climates and can help older or undersized AC units keep up. Houston is squarely in that category.
Rated, not claimed
The Cool Roof Rating Council's Rated Products Directory lists solar reflectance, thermal emittance and SRI. GAF's Unisil data sheet reports CRRC values for Smooth White of 0.83 initial and 0.72 aged reflectance, which GAF notes are approximate.
ENERGY STAR has ended
The ENERGY STAR roof products program ended June 1, 2022, according to CRRC. Ask for CRRC ratings instead of an ENERGY STAR label.
Keep it clean
DOE notes dark algae or mold shows more on light roofs in warm, moist areas, and GAF says silicone may need cleaning to keep its reflectance. Plan a periodic wash.
Sources: U.S. DOE Energy Saver, cool roofs, CRRC, GAF Unisil data sheet.
Cost drivers
How much does silicone roof coating cost?
We do not publish a flat price because the same square footage can vary widely. These are the factors that move the number.
Coating thickness and warranty term
Coverage rate drives material cost. GAF's silicone guidance ties 1.5 gallons per 100 square feet to 10 years of coverage, 2 gallons to 15 years and 2.5 gallons to 20 years, and says each manufacturer sets its own minimums.
- Longer terms need more material
- Mil thickness is verified for warranty
Condition and wet insulation
The moisture survey sets the scope. Every wet area cut out and replaced adds labor and materials before any coating goes down.
- Insulation and membrane replacement
- Deck repairs if found
Prep and detail work
Cleaning, primer where adhesion tests require it, seam and fastener treatment, and mastic at drains and penetrations are often a large share of the job.
- Number of penetrations and curbs
- Primer on difficult substrates
- Rust treatment on metal
Access and logistics
Building height, roof access, occupied spaces below, and the need to stage work around operations all affect labor.
- Lifts or hoisting
- Working around tenants and air intakes
Coverage rates per GAF, when and how to install silicone coatings. Warranty eligibility, terms and coverage are set by GAF and depend on the system and project.
The process
How a silicone roof restoration is installed
A coating is only as good as the roof under it. The sequence below follows GAF's published guidance.
Assess
Roof survey, moisture scan with core cuts, drainage review and adhesion test patches.
Repair
Replace wet insulation and damaged membrane, fix flashings and fasteners, and correct condensate lines that pond water.
Clean
Power wash with a cleaner such as GAF Cleaning Concentrate, rinse the residue and let the roof dry. GAF notes silicone is moisture cure and loses adhesion if the roof is not dry.
Detail
Apply GAF Silicone Mastic to seams, drains and penetrations, and prime where test patches called for it.
Coat
Apply the field coat to the specified rate. GAF's Unisil requires a minimum of two coats; GAF says Unisil High Solids can go on in one coat on slopes of 2:12 or less.
Document
Record thickness checks, photos and findings for the warranty file and your roof record.
Sources: GAF, when and how to install silicone coatings, GAF Unisil data sheet.
Service area
Commercial roof coating across Houston and the Bay Area
Coatings fit different buildings in different parts of the region. Here is where restoration tends to make sense.
Houston, TX
Big-box retail, distribution and office roofs with aging single-ply or modified bitumen are prime restoration candidates when insulation is still dry. Commercial roofing in Houston.
Webster, TX
Medical offices and clinics need low disruption; low-odor coating options and work staged around patient hours keep operations running. Webster commercial roofing.
Clear Lake, Houston
Office and technical buildings around the NASA Johnson Space Center often carry heavy cooling loads, where a reflective white coating can reduce roof heat gain. Clear Lake commercial roofing.
Nassau Bay, TX
Waterfront hotels and offices on Clear Lake face humid air that favors silicone's moisture resistance, along with regular washing to control algae. Nassau Bay commercial roofing.
Seabrook, TX
Bay-front businesses with metal roofs can use a metal restoration system that primes rust and seals fasteners before the field coat. Seabrook commercial roofing.
League City, TX
Retail centers and churches with flat roofs that hold water after storms are where silicone's ponding resistance matters most. League City replacement and coating.
La Marque, TX
Warehouses with aged built-up or modified bitumen roofs can often be restored if a moisture survey shows the insulation is still dry. La Marque commercial roofing.
Dickinson, TX
Commercial buildings near the bay and bayou see frequent heavy rain, so drainage fixes come before any coating decision here. Dickinson commercial roofing.
Santa Fe, TX
Schools, churches and shops with older metal or flat roofs can stretch capital budgets with restoration instead of full replacement when the roof qualifies. Santa Fe commercial roofing.
Pasadena, TX
Industrial roofs exposed to process emissions or grease may call for urethane rather than silicone, with the warranty limits on chemical exposure in mind. Pasadena industrial roofing.
Questions
Commercial Roof Coating: direct answers.
If your question is not here, call Mammoth Services at (832) 416-1566.
- 01
How much does silicone roof coating cost?
It depends on the roof. The main drivers are coating thickness tied to warranty term, the amount of wet insulation and membrane that must be replaced first, prep and detail work, and access. GAF ties 1.5, 2 and 2.5 gallons per 100 square feet of its silicone to 10, 15 and 20 years of coverage. We price after a roof assessment, not by a flat rate.
- 02
Is silicone better than acrylic for a flat roof in Houston?
Often, when the roof holds water. GAF says silicone typically has no warranty exclusion for ponding areas, while ponding can be detrimental to acrylic. Acrylic still fits well-drained roofs and many metal restorations. Silicone's tradeoffs are a slick surface for foot traffic and weaker dirt pickup resistance, so it may need periodic cleaning.
- 03
Can you coat a roof with wet insulation?
Not over the wet areas. GAF describes a restoration candidate as structurally sound and free of wet or damaged insulation. Coating over saturated insulation traps the moisture. The standard approach is a moisture survey, core cuts to confirm, and removal and replacement of wet sections before coating.
- 04
How long does a silicone roof coating last?
The warranty term gives a useful benchmark. GAF links its silicone coverage rates to 10, 15 or 20 years of coverage, and says silicone can be recoated at the end of the warranty without tearing off the old coating if the roof is in good shape. Actual life depends on the roof under it and maintenance.
- 05
Do roof coatings come with a warranty?
Yes, from the manufacturer on qualified projects. GAF lists limited guarantees between 10 and 20 years depending on the system and contractor certification. Its Emerald Pledge specimen requires written leak notice to GAF within 30 days and owner maintenance. Eligibility, terms and coverage are set by GAF and depend on the system and project.
- 06
How do I find out if my roof can be coated?
Start with a roof assessment that includes a moisture survey, drainage review and adhesion testing. Mammoth Services will tell you whether coating, repair or replacement is the right call and why, with photos and written findings. Book at our contact page or call (832) 416-1566.
Sources
- GAF: When and how to install silicone commercial roof coatings
- GAF: Unisil Silicone Roof Coating data sheet
- GAF: Technical Bulletin C-47, Unisil on acrylic-coated roofs with poor drainage
- GAF: Liquid-Applied Emerald Pledge Limited Warranty specimen
- GAF: Roof coating systems
- GAF: How to choose the right roof coating
- GAF: Best use cases for silicone roof coatings
- GAF: Restoring a commercial roof with protective roof coatings
- U.S. Department of Energy: Cool roofs
- Cool Roof Rating Council: ENERGY STAR roofing program sunsets
This page is general information for commercial property owners, not legal, insurance or engineering advice. Warranty eligibility and terms are set by the manufacturer.
Next step
Talk to Mammoth about your roof.
Call Mammoth Services at (832) 416-1566, or book a roof assessment and tell us about your building. For planned work, book a roof assessment call.