TECHOTHANE- PU WHITE

Preparation

All surfaces to be waterproofed should be sound, clean and dry. Concrete surfaces should have a light steel-trowel followed by a fine hair broom or equivalent finish which is dry and free of dust, oil and other contaminants. All high spots should be removed. Moss and laitance must be removed physically followed by treatment with fungicidal wash to kill any spores and inhibit further growth. After treatment wash down thoroughly with clean water and allow drying. All metal surfaces should be made clean of paint, oils, rust and other contaminants.

Priming

Priming is not normally required on good quality concrete substrates. However, absorbent surfaces such as porous concrete sand/cement and cement boards will require sealing to prevent absorption of TECHOTHANE PU WHITE. This should be done using a 1:1 mixture of TECHOTHANE PU WHITE & water.

Cracks

All shrinkage and non-moving structural cracks should be pre-treated with a polymer modified mortar. Allow to cure overnight before general application.

Coverage

1. The dry film thickness (DFT) of TECHOTHANE PU WHITE should not be less than 0.5mm or more than 1.0mm for each coat. Rough or textured surfaces will reduce the coverage rate and consequently more material must be allowed to achieve the minimum DFT.
2. TECHOTHANE PU WHITE is a membrane coating, not paint and as such protection is only achieved with a high film build, i.e. 1 mm on flat surfaces minimum. The membrane can be applied in one 1 mm coat or two 0.5 mm coats maintaining min DFT of 1mm & above.
3. Two coats are recommended on uneven and jointed surfaces to minimize the possibility of thin patches, missed areas and pin holing. Also sloping or vertical surfaces will only accept 0.5 mm per coat. In the case of two-coat application, it is important to re-coat within 24 hours of the first coat becoming sufficiently cured to allow operator access.
4. The minimum application life (after opening the pack) is up to 48 hours if stored in closed containers.
5. A short haired synthetic coating brush should be used.
6. If a water test is to be done, the membrane should be fully cured.
7. Coverage: 1–1.3 kg/m² in two coats and DFT is 1 mm.

Curing and Protection

1. TECHOTHANE PU WHITE membrane must be cured for a minimum of 24 hours @ 25°C before placing protection. Where damage to the membrane is possible (by traffic, backfilling, etc.) it should be protected by a cementitious screed or protection boards. A dust coat of cement should be used to prevent adhesion of the membrane to the boards. Where a bond with the topping is not required, a separator sheet should be used.
2. To prevent damage to the membrane it is recommended that TECHOTHANE PU WHITE is laid in strips of 1 meter width to permit the application of a screed or protection board from the uncoated area.
3. All exposed areas of TECHOTHANE PU WHITE should be coated with Wallnut-5 white to ensure maximum resistance to ultraviolet radiation.
4. Do not store material in opened container for a long time.