Indoor Non Exposed PU Waterproof Coating Water Based Liquid Polyurethane Roofing

Indoor Non-exposed Water-based Polyurethane Waterproof Coating

Water‑based Polyurethane Waterproof Coating‑Bathroom Application & Precautions

Bathroom Application

1. Substrate Preparation Keep bathroom floor and wall solid and flat. Remove dust, oil and loose mortar. Repair cracks and holes with repair mortar. Damp substrate is acceptable, standing‑water is strictly forbidden.
2. Detail Reinforcement Apply 1‑2 coats of water‑based polyurethane as extra reinforcement layer for pipe roots, floor drains and internal/external corners. Width of extra layer ≥250 mm per side. Start main‑surface construction after full drying.
3. Material Stirring Stir thoroughly after opening bucket. One‑component product, do not dilute with water arbitrarily. Seal bucket lid during construction interval to avoid skin formation caused by water loss.
4. Multi‑coats Application Apply thin coats by brush or roller. Single heavy‑coat is prohibited. Apply next coat after previous coat dries, brush in cross directions. Total film thickness for floor ≥1.5 mm; shower‑zone wall height ≥1.8 m, other walls ≥300 mm. Extend interval time under low‑temperature & high‑humidity for slow drying.
5. Curing & Drying Natural air‑dry curing. Avoid water splashing, ponding, treading and sharp‑object damage during curing.
6. Water‑storage Test Carry out 24‑48 h water‑storage test after complete drying. Pass test if no leakage downstairs.
7. Protective Layer & Tile Laying Apply cement‑mortar protective layer after qualified water test, then lay ceramic tiles.

Construction Precautions

1. Suitable construction temperature: 5℃‑35℃. Do not apply on rainy or dewy days, which will cause poor film‑formation and whitening.
2. Never construct on surface with standing‑water, which leads to blistering and delamination.
3. Forbid arbitrary water dilution. Water addition reduces solid content and impairs film strength and water resistance.
4. Apply thin multi‑coats only. Over‑thick single coat may result in incomplete curing, blistering and cracking.
5. Poor ventilation and high humidity greatly prolong curing time. Do not conduct water‑storage test too early for tight schedule.
6. Prevent dust and debris from falling on coating surface before surface‑dry.
7. Clean tools with fresh water right after use. Cured coating can only be removed by mechanical chipping.
8. Average UV‑resistance, suitable for indoor bathroom; not for exposed roof.
9. Keep from freezing during storage. Freezing will break emulsion and disable film‑forming performance.
10. Forbid treading and water exposure before complete curing of film.