Liquid Membrane Coating

Applications

Procedure

1. 1
   Clean the surface of dirt, dust, loose particles, oil, fungus and algae. Re-plaster areas where plaster has come off. Remove any old tar or bitumen felt completely.
2. 2
   Seal cracks first: open them to a U-groove about 6 mm wide and deep and fill with ROOFEXSEAL PU 212. Expansion joints take ROOFEX-SEAL PS. On sheet roofs, laps and bolts take RAINSEAL BXL.
3. 3
   On AC and GI sheet roofs, after sealing the overlap joints and nuts and bolts with RAINSEAL BXL, fix fibre mesh patches (about 4 × 4 inches) over every nut and bolt with a coat of RAINSEAL BMW 250 diluted with 20% water.
4. 4
   Choose the membrane for the surface and its use. Exposed roofs: RAINSEAL 200, RAINSEAL FRC 623, RAINSEAL CFR 613, RAINSEAL RWC 902, RAINPROOF PU 400, RAINPROOF FPU 404 or RAINPROOF PRG 909. Hot roofs: SUMMERSHIELD COOL 666 or SUMMERPROOF COOL 644. Tiled floors kept visible: RAINSEAL CLEAR 202 or RAINCARE PU CLEAR. Under tiles, screed or soil: ROOFCOAT FLEXI 100, ROOFBOND RFX PLUS 210 or ROOFCOAT PU 2K. Soil side: RAINSEAL BMW 250. Decks needing fast return to traffic: RAINPROOF PWR 690, RAINPROOF PHB 660 or RAINPROOF PHW 600.
5. 5
   Prime. Most membranes are primed with a thinned first coat of the same product: RAINSEAL 200 at 1:1 with water, RAINSEAL RWC 902 and RAINPROOF PRG 909 with about 50% water, RAINPROOF PU 400 at 2:1 with water. RAINPROOF PWR 690 is primed with SHINESHIELD WP 305. On porous or AAC block walls, prime with ROOFBOND BCS PRIME 501.
6. 6
   Apply the first full coat, with up to 20% water for the water-based membranes, and bed the reinforcement into it while wet: geo-fabric on concrete roofs, fibre mesh on metal, GI and AC sheets. RAINSEAL RWC 902, RAINPROOF PU 400 and RAINPROOF PRG 909 are stated for use with mesh or geo-fabric; RAINSEAL BMW 250 with glass fibre tissue or geotextile. On sheet roofs the standard build-up is a RAINSEAL RWC 902 primer with 50% water, fibre mesh laid into a coat of RAINSEAL RWC 902 with 20% water, then two coats of RAINSEAL 200 with 20% water.
7. 7
   Apply the following coats at right angles to the last. Recoat times: RAINSEAL 200 and RAINSEAL FRC 623 after 3 to 4 hours, RAINPROOF FPU 404 after 4 to 6 hours, RAINSEAL RWC 902 and RAINPROOF PRG 909 after 6 to 8 hours.
8. 8
   Carry the membrane over the coving and up the parapet or skirting. On external walls, apply two coats of RAINSEAL 200 with 20% water, tinted with a colour stainer where a colour is wanted; high walls are worked from a suspended cradle (jhoola).
9. 9
   Let it cure before rain or water: 3 days for RAINSEAL RWC 902, RAINPROOF PRG 909, RAINSEAL 200 and RAINSEAL FRC 623; 7 days for RAINPROOF FPU 404 and RAINSEAL CFR 613; at least 72 hours for RAINCARE PU CLEAR; 3 to 5 days air cure for ROOFCOAT PU 2K.

Important Suggestions

Why This Treatment?

A liquid membrane forms a continuous film with no laps or joints for water to find. Armstrong makes one for every surface and use: acrylic for UV resistance and heat reflection, rubberised and bituminous for cracked and moving roofs, polyurethane for the longest service, clear coatings that keep the look of tiles, cementitious membranes that go under tiles and screed, and polyurea where a deck must reopen in hours.

Recommended Products

Dosage & Coverage

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