Roof Coatings · an Amrize brand100% silicone, solvent-free liquid roof coating. Highly UV-stable and ponding-water resistant — built for flat and low-slope roofs that hold water. Spray, brush or roller applied.
One coating, three of the most common roofs in Ireland — pick yours and the calculator sets itself up for it.
Flat roofs Felt, asphalt, torch-on and single-ply — S42 lives under ponding water where acrylics fail. Seams sealed, one seamless coat over the lot.
Set the calculator for a flat roof →
Metal roofs Direct adhesion to weathered sheet — and in White it reflects 87% of solar energy, so the sheets run cooler and stop working their fixings loose.
Set the calculator for box profile →
Asbestos roofs Encapsulate, don’t strip — S42 self-bonds with zero drilling or disturbance of the sheets. Allow +20% for the corrugations.
Set the calculator for cement fibre →A moisture-curing elastomeric silicone that goes straight onto most weathered roofs — metal, asbestos cement, aged bitumen, aged single-ply — without a primer.
Silicone chemistry doesn't re-emulsify in standing water — designed for flat roofs that pond, where acrylics fail.
Highly UV-stable. White S4200 reflects 87% of solar energy when new — a cooler roof expands and contracts less, so laps and fixings stay put.
Strong direct adhesion to metal, foam, aged asphalt and aged single-ply. Concrete and some single-ply need a primer — we'll tell you when.
One product, three application routes — and both warranty builds go on in a single coat.
Worked out the way our estimators do it: plan area × pitch factor × corrugation allowance = the developed area your coating actually has to cover. Pail counts use our real per-pail yields for each warranty build.
Figures from the manufacturer's Product Data Sheet (GacoFlex™ S42 Series, rev 06/2025).
| Type | 100% silicone, solvent-free, single-component, moisture-curing |
| Solids by weight / volume | 96% / 95% |
| VOC | < 50 g/L |
| Tensile strength | 1.9 MPa |
| Elongation at break | 196% |
| Water swelling | 0% |
| Solar reflectance (initial / 3-yr) | 0.87 / 0.69 |
| Min dry film per coat | 0.45 mm (18 mils) |
| Application | Brush, 19 mm nap roller, or spray |
| Application window | 0°C to 48°C; no rain within 1 hour |
| Light foot traffic | After 24–48 hrs cure |
| Colours | White S4200 · Grey S4222 |
Coloured silicones are not used over asphalt substrates. Concrete needs GacoFlex E5691 epoxy primer first.
One coat at the 18-mil TDS build. Manufacturer-backed product warranty, issued through Duratite Building Products.
Still one coat — just applied at the heavier 34-mil TDS build. A white-then-grey two-coat split is an option on slopes where you want coverage visible as you go, but one coat at the full build qualifies.
Duratite's warranty QA requirement: comb-gauge wet-film readings across the roof so the build that earns the warranty is proven, not assumed.
A warranted silicone roof is cleaned → seams sealed → coated. Buying the full system is what qualifies the warranty.
The same pail, doing the job it's sold for.
Metal roof 687 m² of weathered metal roof coated as one continuous, seamless membrane — no strip-off, no disruption below.
687 m²S42 system See our case studies →Torquay, England · Flat roof A failing town-centre flat roof waterproofed with the full silicone system — seams sealed, coated white around every penetration.
Gaco S42Flat roof Read the case study →
Bournemouth, England · Terrace roof S42 roller-applied over a terrace flat roof — the white-then-grey option in action, so full coverage is visible as the coat goes on.
Gaco S42Roller applied Read the case study →Trade accounts get volume rates, priority stock and 30-day terms. Speak to a Duratite expert on info@duratite.ie.
Tell us about your building and we’ll recommend the right system — foam, waterproofing or both — surveyed, specified and quoted at no cost.
