Description
ARDEX WPM 155 Rapid Plus is a modified polyurethane hybrid waterproofing membrane designed for application under tiles or screed, internally and externally. It is compliant to both AS 4858 (internal wet areas) and AS 4654 (external above-ground), micro-fibre reinforced, and formulated so that it will not re-emulsify once cured. Manufactured by ARDEX Australia.
The “Rapid Plus” part is the schedule. The membrane is totally dry 3 to 4 hours after the final coat at 23 degrees C and 50% relative humidity, and direct tiling or screeding can begin at that point – so a bathroom floor waterproofed in the morning can be tiled the same afternoon rather than the next day. Recoat time between coats is 1 to 2 hours. Also written ARDEX WPM155.
Technical Specifications
| Product type | Modified polyurethane hybrid liquid-applied membrane |
|---|---|
| Standards | Compliant to AS 4858 and AS 4654 |
| Colour | Light blue |
| Specific gravity (mixed) | 1.35 kg/L |
| Solids content | 74% |
| Elongation | Class III (AS 1145.3) |
| Tensile strength | 1.33 MPa (AS 1145.3) |
| Bond strength | 28.0 N (ASTM C794) |
| Water absorption | 1.89% (AS 3558.1) |
| Moisture vapour transmission | 4.21 g/m²/24 hours (ASTM E96) |
| Cyclic movement | Pass (AS 4858 Appendix B and AS 4654.1 Appendix B) |
| Durability – immersion and heat ageing | Pass (AS 4858 Table A1, AS 4654 Table A4) |
| Wet film per coat | 0.5 mm |
| Dry film per coat | 0.25 mm |
| Total dry film (2 coats) | 0.5 mm |
| Recoat time | 1-2 hours at 23 degrees C and 50% RH |
| Dry time | 3-4 hours at 23 degrees C and 50% RH |
| Full cure (immersed areas) | 72 hours at 23 degrees C and 50% RH |
| Application temperature | 10 degrees C to 35 degrees C, ambient and substrate |
| Packaging | 15 L and 4 L pails |
| Shelf life | 12 months unopened, stored dry at 23 degrees C and 50% RH |
Coverage Rates
Coverage is quoted at 0.5 mm total dry film thickness, applied as two coats of 0.5 mm wet film each.
| Pail | Coverage at 0.5 mm DFT, 2 coats |
|---|---|
| 15 L drum | Approx. 17.5 m² |
| 4 L drum | Approx. 4.5 m² |
Coverage rate may vary depending on application technique. Allow additional material for detailing at junctions, penetrations and joints.
Where to Use
- Podiums
- Terraces
- Balconies
- Internal wet areas including bathrooms and showers
- Under tile and under screed applications, internal and external
How to Apply
- Prepare the substrate – remove all dirt, dust, curing compounds, oils, grease, surface sealers and existing coatings by mechanical methods and vacuum as necessary. The surface must be sound, clean, dry and free from sharp edges. Damaged concrete between 2 mm and 30 mm can be made good with ARDEX A 46; spalling concrete needs the ARDEX Concrete Repair range.
- Prime – ARDEX WPM 300, ARDEX WPM 265 or ARDEX Multiprime may be used on prepared substrates, and ARDEX P9 Single Part Primer on non-porous surfaces. Where masonry or concrete moisture exceeds 80% relative humidity (ASTM F2170) or 15 g/m²/24 hrs (ASTM F1869), a minimum of two coats of ARDEX WPM 300 HydrEpoxy must be used as the primer.
- Detail the junctions – seal around drains, penetrations, floor/wall and wall/wall junctions, joints and substrate changes before the general coats, using ARDEX STB/STA Tape, ARDEX neutral cure silicone, or ARDEX CA 20 P PLUS / RA 050 sealant. Tape overlaps must be at least 50 mm. Silicone bead sizes are 12 mm (6 mm x 6 mm) for wet areas and 15 mm x 15 mm externally. Avoid three-sided adhesion and follow Australian waterproofing standards for bond breaking and coving.
- Apply the first coat – stir the contents before use. Apply by brush or roller at 0.5 mm wet film thickness. Do not add solvent or water.
- Apply the second coat – after 1 to 2 hours at 23 degrees C and 50% relative humidity, apply the second coat at 90 degrees to the first, again at 0.5 mm wet film, giving 0.5 mm total dry film.
- Cure and check – the membrane is totally dry in 3 to 4 hours. Inspect before flood testing, which may commence at 72 hours; apply an additional coat if damage, imperfections or pinholes are found. Clean equipment with water and detergent before the product dries.
Important Notes
- Do not apply if ambient or substrate temperature is below 10 degrees C or above 35 degrees C, or if rain is imminent.
- Not for permanently submerged environments such as swimming pools and spas.
- Not designed as a stand-alone UV-exposed or permanently trafficable membrane.
- Must not be left exposed for longer than 5 days before recoating, direct tiling or direct screeding. After longer exposure the cured membrane may need cleaning with mild detergent and water, then full drying, before overcoating.
- Do not add solvent or water to the product.
- Areas over ARDEX STB Tape or ARDEX sealant dry slowest – these must be completely dry before tiling or screeding.
- Immersed areas such as showers must not be used until full cure at 72 hours from the final coat.
- Store in the original unopened packaging in a dry place; shelf life is 12 months at 23 degrees C and 50% relative humidity.
Frequently Asked Questions
How much area does a pail of ARDEX WPM 155 Rapid Plus cover?
A 15 litre drum covers approximately 17.5 square metres and a 4 litre drum approximately 4.5 square metres, both at 0.5 mm total dry film thickness applied in two coats. Coverage varies with application technique and substrate texture. The membrane must be applied at 0.5 mm wet film per coat, which gives 0.25 mm dry film per coat and 0.5 mm total over two coats.
How long before you can tile over ARDEX WPM 155 Rapid Plus?
Direct tiling or screeding may begin 3 to 4 hours after the final coat at 23 degrees C and 50% relative humidity, which is also when the membrane is totally dry. Recoat time between coats is generally 1 to 2 hours under the same conditions, with the second coat applied at 90 degrees to the first. Immersed areas such as showers should not be used until the membrane reaches full cure at 72 hours, and flood testing may start at 72 hours. Areas over ARDEX STB Tape or sealant dry slowest and must be completely dry before tiling.
Can ARDEX WPM 155 Rapid Plus be used in a swimming pool?
No. ARDEX WPM 155 Rapid Plus is not to be used in permanently submerged environments such as swimming pools and spas. It is also not designed as a stand-alone UV-exposed or permanently trafficable membrane, and must not be left exposed for longer than 5 days before recoating, tiling or screeding.
