Polymer Modified Asphalt Waterproof Coating Specially For Pipe Roots And Corners

Liquid Membrane Waterproof Coating

Construction Method for Basement Waterproofing

1. Base Surface Treatment

1. Make concrete bedding / wall base solid and flat. Remove laitance, dust, oil stains, steel bar ends and sharp protrusions. Repair honeycombs, holes and cracks with polymer mortar for leveling.
2. Form R50 mm circular arcs at internal and external corners (joint between floor and exterior wall). Compact the surrounding areas of through‑wall sleeves and pile heads. Polish construction joints and post‑pouring belts thoroughly.
3. No standing water on substrate. Moisture content ≤9% for water‑based liquid membrane. Apply matching primer to reinforce loose and sanding base surfaces.
4. Fill and compact grooves of expansion joints with sealant.

2. Additional Layers for Details (Key Points for Basement)

Construction sequence: Treat details first, then large‑area surfaces.

1. Locations: internal and external corners, through‑wall pipes, pile heads, post‑pouring belts, construction joints, deformation joints.
2. Width of additional layer ≥500 mm, adopt two‑coat‑one‑fabric process:
   • Apply the first thin coat of liquid membrane;
   • Lay polyester non‑woven fabric / glass‑fiber fabric, ensure full saturation without hollowing, wrinkles or edge curling;
   • Apply the second coat after surface‑dry to fully cover reinforcement fabric, fabric shall not be exposed.

3. Large‑Area Waterproof Membrane Construction

1. Stir material thoroughly with electric mixer after opening drum. Do not dilute with water or solvent.
2. Application methods: roller coating, scraper coating or spray coating. Apply multiple thin coats in cross directions. The direction of subsequent coat shall be perpendicular to the previous one. Thick single‑coat application is forbidden to avoid blistering and incomplete curing.
3. Apply next coat only when previous coat is surface‑dry and non‑tacky. Interval: 2‑6 h at normal temperature; 8‑24 h under low‑temperature and humid conditions.
4. Total dry‑film thickness for basement ≥2.0 mm (2.0 mm is preferred due to high underground water pressure), apply in 2‑3 coats. Theoretical consumption: approx. 2.6‑3.0 kg/㎡.
5. For vertical exterior walls: avoid over‑thick single coat to prevent sagging. Reinforcement fabric can be added on vertical surfaces to improve water‑pressure resistance.

4. Curing, Protective Layer & Acceptance

1. After full membrane application, cure for 48‑72 h at normal temperature. Extend curing time under low‑temperature and high‑humidity conditions. Do not backfill soil, cover or tread before full curing.
2. Construct protective layer immediately upon waterproof layer acceptance:
   • Floor: fine‑aggregate concrete protective layer;
   • Exterior wall: polystyrene board protective wall / cement mortar protective layer, then backfill soil. Sharp stones in backfill shall not impact waterproof membrane directly.
3. Water‑storage test can be carried out for floor. Inspect membrane integrity without damage before exterior wall backfilling.

5. Notes for Basement Construction

1. Suitable construction temperature: 5℃‑35℃. Do not construct below 5℃ to prevent demulsification and failure. Stop construction in rainy weather, dew condition, with standing water on substrate or wind force ≥Grade 5. Ambient humidity shall not exceed 85%.
2. Sediment at drum bottom is normal; stir well before use. Use up opened material within the same day as much as possible. Discard caked or demulsified material.
3. Reinforcement fabric shall be fully saturated, no white core or hollowing. Cut and repair hollow positions before continuing coating.
4. Ventilation is poor in basement, enhance air circulation during construction. Avoid prolonged skin contact with coating.
5. Chiseling and sharp‑object impact are prohibited in follow‑up works after membrane completion. Any damaged area must be repaired before protective layer application.