Metal Roof Coating and Painting Systems Compared
Silicone Coatings
Silicone is the coating most roofers reach for on metal. It sticks well and moves with the panels as they heat and cool. It also tolerates standing water, which is why manufacturers market it for roofs that pond. The Florida Building Code lists ASTM D6694 as the standard silicone roof coatings must meet. A few practical limits:
- Thickness. About 22 dry mils for a 7-year warranty on one system; longer warranty tiers call for heavier specifications.
- One-coat limit. One maker allows a single heavy coat only on roofs of 2:12 or flatter.
- Surface temperature. Between 40 and 150 degrees Fahrenheit during application on one system.
Acrylic Elastomeric Coatings
Acrylic elastomeric coatings are water-based and usually white, and the code holds them to ASTM D6083. Florida also has its own test protocol, TAS 143, for white elastomeric coatings on metal roofs that are sloped to drain. That hints at the dividing line: acrylic suits a pitched roof that sheds water, and silicone suits a low roof that holds it.
Rust Primer and Spot Treatment
Coating over rust traps it. The prep step is to wire-brush loose, flaking rust and then apply a rust-inhibitive primer, one coat on bare metal or two over an old painted finish on one system. HomeGuide puts rust repairs at $300 to $3,000. Panels rusted through are a repair job, not a coating job, and get replaced first.
Seam and Fastener Sealing Before Coating
On an exposed-fastener roof, the coating only lasts if the seams and screws under it are sound. The sequence one manufacturer publishes runs like this. Loose or missing screws are tightened or replaced, the roof is power washed, and an adhesion test confirms the coating will stick. Then lapped seams get mastic, ridges and rakes get mastic with embedded fabric, and every screw head is encapsulated. Typical standing seam profiles don't need the seam treatment.
Repainting Faded Panels
Repainting is the answer once a wash no longer brings the color back and the panels stay chalky after cleaning. It keeps the roof's profile and look, but a field paint is not the same as the PVDF finish applied at the factory. Ask what paint is going on, whether it is made for metal roofing, and how many coats the price includes.
Why Pompano Beach homeowners call Pompano Metal Roofing
- One independent roofer per request, never a call list
- Ask for tear-off, deck repair and permit as separate lines
- No fee to homeowners for the referral or the estimate
- Your details go to that one roofer and nobody else
Metal Roof Coating Candidates: What to Check First
Panels still sound
Light rust and chalking can be coated. Holes and rusted-through panels can't.Adhesion test
A small test patch shows whether the coating bonds to your old finish.Approval and permit
In Broward, every roofing component is supposed to carry a product approval, and permits cover roof maintenance as well as repair. Ask for the coating's approval number and whether the job needs a permit, or ask the City's Building Inspections office.Photos
One coating warranty requires photos before work, after prep, after detailing and after coating. Ask for copies.Clean first
Coatings need a clean, dry surface. If the roof only looks dirty, cleaning may be all it needs.