Ardex WPM 415

Ardex WPM 415

ARDEX WPM 415 is a one component, penetrating crystalline waterproofing powder formulated from Portland cement, it is used specially for treated quartz sand and active chemicals. ARDEX WPM 415 waterproofs and protect concrete or masonry render through the crystallization process.

The unique reactive chemicals penetrate and become an integral part of the concrete where the crystals reacts permanently in the presence of water. ARDEX WPM 415 is suitable for use in damp surface and high water pressure applications on both the positive and negative side.


No odor and no fumes - environmentally friendly

Easy to use - requires only water for mixing

Fast setting - two coats can be applied the same day

Not a vapour barrier - allows the substrate to ‘breathe’

Seals and post seals shrinkage cracks, up to 0.4mm

Brush/spray applied in +ve/-ve pressure applications

Inorganic and non-toxic - Non-flammable


Residential , commercial applications for floors & walls

Waterproofing of below grade foundations,basements ,retaining walls,elevator pits,subway stations

Marine structures such as docks, piers and aquariums

Water tanks , tunnels , dams , sewerage plants , swimming pools , parking garages , decks , balconies and roofs


New and old conrete of interiour and exterior construction


Remove the remaining concrete fins and projections, general surface dirt, grease, oil and other contaminants. Use steam cleaning, high-pressure water blasting, wet or dry sand blasting, wire brush or other mechanical methods to produce surfaces suitable to allow ARDEX WPM 415 to penetrate.

Clean and prepare surfaces and seal cracks and joints.

Stable construction joints and visible cracks (> 0.4mm) should be raked out to 20mm width and 25mm depth. Before brushing the area with two coats of ARDEX WPM 415, use ARDEX Primer to fill up the joint.

Ensure that there are no water leakages, the surfaces must be strictly sound and clean from residue, oil, sealers, waxes, contaminants and laitance. Holes, cracks and deteriorated area are seal for maximum penetration

Saturate the surfaces with clean water to minimise surface suction and maximise crystal formation. Surface shall be moist but not wet when ARDEX WPM 415 is applied. Remove any surface water that is on the horizontal surfaces .


Add 7.5 - 8L of water to 25kg bag of WPM 415 powder and mix thoroughly until the mixture is completely free of lumps. Re-mix the used ARDEX WPM 415 within 40 minutes. If the mixed material starts to “pseudo setting”, re-stir to restore the workability.


Apply 1st coat in a slurry consistency and evenly by a masonry brush. Work well into the prepared substrates. Apply 2nd coat within 30-60 minutes whilst the first coat is just touch dry.

ARDEX WPM 415 may be applied with appropriate compressed air spray equipment according to the specifications, in perpendicular movements.

Clean the tools and equipment immediately after use with water.


Protect the freshly treated ARDEX WPM 415 surface from rain and traffic for 24 hours.

Ensure that the freshly treated ARDEX WPM 415 is moist cure for at least 48 hours.

Further cementation plaster, render finish or tiling system can be applied onto treated ARDEX WPM 415 at 48 hour after completion.

Coating or painting on ARDEX WPM 415 treated surface should be applied 2 weeks after completion. Recommend neutralizing the surface with water or an appropriate acid, e.g. diluted vinegar solution or diluted muriatic acid (1:8 to water) for better bonding


Do not apply ARDEX WPM 415 at temperatures below 5oC or onto dry substrates.


Application Number of coatsRate/coat(kg/m2)
Normal internal & external surface for waterproofing1 - 20.7 - 0.8
Concrete for waterproofing & hydrostatic pressure resistance20.8 - 1.0
Concrete slab, concrete component - by dry spreading11.4 - 1.6


ARDEX WPM 415 is packed in paper sacks - net weight 25kg.


ARDEX WPM 415 should be stored in the original unopened packaging in cool and dry warehouse at 23oC and 50% relative humidity. When stored under the correct conditions ARDEX WPM 415 will have a shelf life of 12 months.



Product Properties

Single Part






Bulk density:

Approx. 1.36 - 1.4 kg/litre


12+ 1



Pot Life:

(28C & 60% R.H.)

>40 mins

Setting time:

(28C & 60% R.H.)

Initial > 120 minutes

Final < 180 minutes

Testing Method


Water Permeability 

(JIS.A6101 / DIN 1048)

No measurable leakage up to 15kg/cm2 for 48 hours after 28 days curing

Depth of Max Penetration (DIN 1048)

> 20mm after 28 days curing

Water Absorption (ASTM C642)

Up to 25% decrease the un-treated samples at 28 days curing.

Compressive Strength (ASTM C39)

+10% at 28 days over un-treated samples

Bonding Strength (ASTM D4541)

+10% increase in cementation adhesion

Flexural Strength (ASTM C348)

+10% at 28 days over un-treated samples

Efflorescence Resistance (ASTM C67)

No affected on treated surface

Freeze-Thaw Resistance (ASTM C67)

50 cycles ( -18C ~ -23C) - weight loss of less than 0.5%

Salt-attack Resistance (ASTM C67)

No affected on treated surface