Method · Liquid-applied waterproofing
Silicone is very UV-resistant, tolerates ponding water and can be applied over an aged one — so a roof can be restored without stripping the old layer.
A silicone coating with excellent UV resistance, among the best of the liquid systems. It can be coated over an aged membrane.
Re-roofing: renewing a tired roof without tearing off the old membrane.
The old membrane must still be sound and clean — we survey it first.
Layers (built up from the bottom)
Applied once coat 1 has dried, giving a seamless film.
The first coat over the whole roof. Seams and bolt heads are sealed with a separate material.
Stops the asphalt from bleeding through into the coating above.
The roof before coating, cleaned and dried.
The figure shows one typical build-up. The actual layers are decided after we see the site.
We inspect the substrate — moisture, cracks, laitance — before choosing the system. A wrong substrate defeats any membrane.
Roofs and tanks get a water (ponding) test before handover; the result is signed off jointly.
Liquid membranes are chosen by where they go and the conditions on site. If another one fits better, we will say so.
| Membrane | Strength | Where |
|---|---|---|
| Acrylic (water-based) | Paint-like, cheapest | Roof, exterior wall |
| Bituminous Liquid | Liquid asphalt, low-cost, below ground | Below ground |
| Polyurethane (PU) | Flexible; Aliphatic grades are UV-stable | Outdoor — roof, deck |
| Polyurea — Pure / Hybrid | Sets in seconds; drinking-water tanks take a potable-certified grade | Water tanks |
| Siliconethis page | Very UV-resistant; ideal over existing membranes | Over existing membranes (repair) |
| PMMA (Methyl Methacrylate) | Works through the rainy season, rain-resistant in about 30 minutes at 20 °C | Metal-sheet roof, deck, roof garden, joints |
| STPE | Goes onto damp (not wet) substrates | Basins & pits, enclosed damp areas, non-absorbent substrates |
Also with this method:Sirindhorn Dam Power Plant (EGAT)
The area, the state of the substrate (cracks, wet spots, or an old membrane to remove), the system and number of layers, whether it is exposed to the sun, and the hours we can work. Send photos and drawings on LINE and we will check the site and quote.
Yes, as long as the existing membrane is sound and clean. We check that on site first.
Silicone is very UV-resistant, tolerates ponding water and is ideal over existing membranes. Polyurethane is a highly elastic membrane for outdoor roofs and decks; its standard grade needs a UV top coat where exposed.
Send the area, the substrate and a few photos. We check the site and propose the membrane that fits.
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