Technical Reference

Treatment Procedures.

Step-by-step waterproofing, structural repair and rehabilitation methods, grouped by the chemistry they use, each mapped to the Armstrong products that carry it out. Select a treatment to view the full procedure and product recommendations.

Choose a treatment

Treatment · Cementitious & crystalline

Crystalline Waterproofing

Crystalline technology for positive and negative water pressure

Applications

Basements and cellarsLift pitsSumps and tanksRetaining wallsConstruction jointsWater-retaining structures

Procedure

Expose the concrete. Remove paint, putty, plaster and every loose or flaking layer with wire brushes and chiselling equipment. A crystalline coating must touch bare concrete.
Stop running water and rebuild joints and honeycombs first.
Wash and dampen the surface well so the pores are full, with no water standing on it.
Mix ROOFEX COP or ROOFEX with water to a slurry and brush it on, working it into the surface, joints and fillet. ROOFEX goes on at 0.75 kg per sq.m per coat. ROOFEX COP covers 0.75 to 1 sq.m per kg per coat.
Apply the second coat at right angles to the first, at the same rate. With ROOFEX COP, apply it within 48 hours while the first is still green.
Moist-cure: mist the coating with a fine spray 3 to 4 times a day for 2 to 3 days.
Where the wall will be plastered or knocked by use, protect the cured coating with ROOFCRETE AR or a sand-cement plaster modified with ROOFBOND SBR 401.

Important Suggestions

Do not use a membrane curing compound on a crystalline coating, because it blocks the surface. For higher water pressure (10 to 12 bar) or masonry walls, use the two-component ROOFEX 2K 711. At construction joints, ROOFEX is applied as a slurry or dry powder at 1.5 kg per sq.m before the next pour.

Why This Treatment?

When water comes from the negative side, from groundwater, and the outside cannot be excavated, crystalline technology is the answer. It reacts with the moisture in the concrete to grow insoluble crystals in the pores and capillaries, seals cracks up to 0.4 mm and lets the concrete breathe.