David Contreras, owner of DC Roofing of Arizona, has been roofing in Tucson since 2011, and he walks every Oro Valley roof we estimate before recommending a coating. Silicone is the coating we reach for most often on flat roofs, mainly because it handles standing water better than the alternatives. It also comes with trade-offs, and one of them is permanent: once a roof is coated with silicone, it stays a silicone roof. This page covers where silicone makes sense, what to know before you choose it, and how we apply it. We're licensed, bonded, and insured (ROC #328733), with $1M per occurrence and $2M aggregate in general liability coverage, and manufacturer-certified with GAF, Polyglass, and APOC.
Why Silicone Handles Water Better
Flat roofs rarely drain perfectly. A slight sag, a drain partly blocked with leaves, or a section that settled over the years can leave water sitting after a storm. Roofing manufacturers generally call it ponding when water is still there 48 hours after the rain stops.
Acrylic coatings soften and wear away where water sits. Silicone is made to tolerate it, which is why it's the usual choice for roofs with low spots. That doesn't make ponding harmless. Standing water still adds weight, collects dirt, and points to a drainage problem. When we can correct a low spot or clear a drain, we do that too.
Silicone also holds up well to UV and stays flexible through big daily temperature swings, which is most of what a coating has to survive here.
The Trade-Offs to Know First
- It's a one-way door. Almost nothing but silicone will stick to cured silicone. Every future recoat and repair on that roof has to be silicone. If you might want a different system later, that matters now.
- It picks up dirt. Silicone surfaces tend to hold onto dust, and a dirty roof reflects less sun. Rinsing with plain water helps keep it bright.
- It's slick when wet. Something to keep in mind if a service tech needs to walk the roof after rain.
- It costs more than acrylic. On a roof that drains well, an acrylic elastomeric coating can do the job for less, and David will tell you if that's your situation.
What Silicone Can Go Over
Silicone bonds to most flat roof surfaces we see, including foam, older acrylic coatings, EPDM, and built-up roofs. Each one needs its own preparation, and some need a primer. Before we commit to a whole roof, we do an adhesion test on a small area to make sure the coating will actually stick to what's there. It's a simple step, and skipping it is how coatings peel in sheets.
Silicone isn't for tile roofs, and it isn't a fix for a roof that's already failing. If the deck is soft or the insulation underneath is wet, coating over it traps the moisture in. Those problems get repaired first, or we'll tell you the roof needs more than a coating.
Oro Valley: Permits and HOAs
Oro Valley is an incorporated town, so it sets its own permit rules. The Town's permit page lists replacing a roof covering without replacing the sheathing as work that doesn't need a building permit, and roof coating isn't on its list of projects that do. If a repair involves replacing sheathing, check with the Town first. Oro Valley also has many master-planned communities with HOAs. A coating on a flat roof behind a parapet usually isn't visible from the street, but if your association reviews exterior changes, check with it before work starts.
How We Apply It
David walks the roof and checks drainage, seams, penetrations, and whether anything underneath is wet. We pressure wash the surface, repair cracks, blisters, and open seams, seal pipes and vents with a 3-course mastic method, test adhesion, prime where the surface calls for it, and apply the silicone at the thickness the manufacturer specifies. There are no salespeople and no subcontracted crews: our own crew does the work, with David on site. Our coating jobs carry a 5-year labor warranty, and every project we complete includes free annual inspections. Applied at the right thickness, silicone typically lasts about 10 years before it needs another coat. For the full process and how timing works around monsoon season, see our silicone roof coating page.
FAQ: Silicone Roof Coating in Oro Valley
Is silicone worth the extra cost over an acrylic coating?
On a roof where water sits after storms, usually yes, because silicone tolerates ponding and acrylic breaks down there. On a roof that drains well, an acrylic elastomeric coating can do the job for less. David will tell you which one your roof actually needs.
Can I switch back to an acrylic coating later?
Not without removing the silicone. Acrylic and most other coatings won't bond to cured silicone, so once a roof is coated with silicone, every future recoat and repair has to be silicone too.
Can silicone go over my existing roof coating?
Often, yes. Silicone can go over many existing surfaces, including older acrylic coatings and foam, after cleaning and repairs, and sometimes with a primer. We test adhesion on a small area before coating the whole roof, so you know it will stick.
Does a silicone roof get dirty?
Silicone tends to hold onto dust more than some other coatings, and a dirty roof reflects less sun. Rinsing it with plain water helps keep it bright. We look at the surface during the free annual inspections that come with every project.
Do I need a permit or HOA approval for a silicone coating in Oro Valley?
The Town of Oro Valley's permit page lists replacing a roof covering without replacing the sheathing as not needing a building permit, and coating isn't on its list of projects that do. Many Oro Valley neighborhoods have HOAs, so if yours reviews exterior changes, check with it first.
How do I know if my roof has a ponding problem?
Look at the roof a day or two after a real rain. If water is still sitting in the same spots 48 hours later, that's ponding. Stains or dirt rings on a flat roof show where water has been sitting before. We check drainage as part of every coating inspection.
How long will a silicone coating last?
Applied correctly, silicone is usually a one-time coat that lasts about 10 years. How long yours lasts depends on how thick it was applied, how well the roof was prepped, and how much water sits on it. Our coating jobs carry a 5-year labor warranty.
