Common Issues and Solutions in JS Polymer Waterproof Coating Construction

Specific Causes:

1. The base layer is too dry; after the waterproof coating is brushed, air trapped on the surface of the base layer escapes, causing pinholes in the waterproof membrane;

2. WaterproofCoatingDuring construction, insufficient brushing; the waterproofCoatingflows on the surface of the base layer without fully saturating, thus leading to the formation of pinholes.

Solution:

Before applying the waterproofCoatingensure the base layer is thoroughly saturated with water, and wait for surface moisture to evaporate before proceeding with the waterproofCoatingbrushing;Use a trowel application method, which ensures better adhesion between the waterproofCoatingand the base layer;One-time application should not be too thick—apply multiple thin coats instead.

Specific Causes:

Due to unevenness, softness, looseness, or large amounts of oil stains and debris on the base layer, the bond between the waterproof membrane and the base layer becomes unstable.Water Tightness TestWhen performed, water pressure causes the membrane to contract again.

Solution:

For minor unevenness or oil stains on the base layer, apply additional coating to reinforce the area.Edge StripStrengthen the base layer by removing voids, cracks, and weak areas on the surface; for severe structural weaknesses across the entire base layer, re-level it.In cases where overall strength is inadequate, re-level the base layer.

Specific Causes:

Applying the waterproof coating vertically on the wall surface, when not fully dried, flows downward, causing material accumulation at corners and pipe junctions. This results in excessive thickness, while the surface dries quickly due to faster evaporation, forming a hard crust. Meanwhile, internal layers remain uncured. During subsequent curing, internal stress pulls apart the already hardened surface layer, causing cracking.

Solution:

Repair cracked areas by performing chamfering treatment before work begins. Avoid material buildup at corners and pipe joints. Apply a polymer cloth or mesh over the treated surface.Polymer Clothor mesh fabric, then re-apply the waterproof coating. This enhances the membrane's tensile resistance and improves bonding with the base layer, preventing future cracking.

Specific Causes:

Insufficient flatness of part of the base layer causes the waterproof coating to accumulate in low spots. The surface layer dries first, while the inner layer remains uncured. This difference in shrinkage creates internal stress, leading to surface cracking.

Solution:

Inspect the base layer before work begins. Repair any defects such as holes, cracks, or irregularities in advance. Follow the principle of multiple thin coats during waterproofing—avoid excessively thick single applications. Prevent material buildup.

Specific Causes:

The inherent hydrolysis reaction of the waterproof coating may cause white discoloration on the surface; factors like base layer absorption rate, environmental temperature, wind speed, etc., also affect drying.Curing Speed, the longer the curing time, the more likely alkaline substances will migrate and accumulate on the surface, resulting in white discoloration.

Solution:

Hydrolysis is a normal phenomenon and cannot be completely avoided. Surface whitening generally does not affect waterproof performance. Additionally, ensure the base layer is dry with no visible moisture, improve ventilation, and increase air circulation speed to reduce the occurrence of whitening.

JS Waterproof Coating Construction Guidelines!

1. What are the main steps in household waterproofing construction?

Base Layer Preparation → Address Critical Points → First Coat → Second Coat → First Water Test → Protective Waterproof Surface → Second Water Test → Project Quality Acceptance.

2. What is the most critical step in waterproofing construction?

The most critical steps are base layer preparation and detailed point reinforcement. A well-prepared base layer is key to successful waterproofing, and detailed reinforcement helps maintain structural integrity and proper function of the waterproof layer.

3. How to handle the base layer?

(1) The ground drainage slope must meet design requirements;

(2) The base layer must have sufficient strength, be solid, level, and free from bulges; it should have no standing water or dampness;

(3) Contaminants like oil, grease, dirt, and debris on the surface must be cleaned thoroughly;

(4) At junctions between horizontal and vertical surfaces, corners, and shadowed areas, use a waterproof mortar to create small rounded fillets;

(5) For pipes, sanitary fixtures, floor drains, and other connected elements, install and seal them tightly before waterproofing. Only proceed with the waterproof layer once they are fully installed and secured;

(6) The pipe surface must be treated with reinforcement or sealing measures.

4. What principles should be followed when applying the waterproof coating, and what standards should be met?

Apply the coating following the sequence: first detailed points (pipes, downspouts, etc.), then large areas (walls and floors). Round corners into smooth curves. Before large-area waterproofing, fill and seal all gaps within the joints according to design specifications. At roof edges, eaves, corners, pipe joints, and other critical points, pre-brush two coats of coating. The coating must be fully applied, with no leaks or gaps, firmly bonded to the base layer. No air bubbles, cracks, peeling, or unevenness should appear. The surface must be flat and uniform, with consistent coating thickness meeting product specifications. Work must follow the schedule outlined in the product instructions. Complete all waterproofing tasks before proceeding with subsequent construction steps.

5. Is it better to apply the waterproof coating thicker?

No. SomeFresh Waterproof Materialsapplied too thickly may easily develop cracking. Avoid one thick coat—use multiple thin coats instead.

6. What specific waterproofing requirements exist for different rooms?

All floors and walls in bathrooms, kitchens, balconies, basements, and living units must be waterproofed. Internal plumbing pipes and joints must also be waterproofed. When pipes or drains cross floor slabs, the waterproof layer around the penetration must be carefully applied. Internal plumbing pipes should extend beyond the joint diameter; apply a round sealant inside the joint and then coat the waterproof layer. Note: If original drainage or sewage lines or floor drain locations are changed during renovation, additional waterproofing measures must be implemented around the affected area.

7. Which key stages require supervision during waterproofing construction?

① All waterproof areas must be fully covered;

② Waterproof application must strictly follow the product manual—apply the correct thickness and coverage;

③ Work must be meticulous: joints between walls and floors, corners, pipes, floor drains, sanitary fixtures, and the interior of HVAC ducts are key waterproof zones. Special attention must be given during application.

8. Why perform a water test after waterproofing is completed?

A water test verifies whether the waterproof layer performs effectively. Seal doors, windows, and floor drains. The water depth at the highest point should be no less than 20 mm. Maintain water for at least 24 hours, then check for any leakage points.

9. How to determine if the waterproofing is done properly?

Primarily through water testing. Visual Inspection: Open the basement bathroom or similar area to check for water seepage or puddles. Touch Inspection: Use your hand to feel suspected areas to confirm whether there is leakage.