How to Waterproof Prefabricated Concrete Houses

Waterproofing of prefabricated concrete houses requires systematic treatment from material selection, construction operations, to post-maintenance. The specific steps are as follows:

1. Determine Waterproofing Materials

Select appropriate materials based on the usage scenario:

• General-purpose materials: Organosilicon waterproofing agents, cement mortar waterproofing agents, etc., which need to possess durability, water resistance, corrosion resistance, and good bonding strength.
• Special-scenario materials:
  • Basements: Cementitious capillary crystalline waterproofing agents, which can self-generate crystals to block pores and form a deep waterproof barrier.
  • Kitchens and bathrooms: Acrylic polymer emulsion mixed with cement to form a flexible waterproof layer that adapts to minor structural deformations.

2. Substrate Preparation and Material Inspection

• Substrate cleaning: Thoroughly remove surface oil, dust, and loose particles. Repair cracks or uneven areas to ensure the substrate is flat, dry, and solid.
• Material inspection: Confirm that the waterproofing materials have no sediment, clumping, or expiration. Organosilicon waterproofing agents need to be stirred until uniform and free of particles. Polymer emulsion mixed with cement should be prepared into mortar at a ratio of 1:0.5 and used within two hours.

3. Waterproof Layer Construction

• Material preparation: Mix cement, sand, water, and waterproofing agents according to the instructions. For example, mix organosilicon waterproofing agent with cement at a ratio of 1:1 and add water, stirring until no clumps remain.
• Application technique:
  • Apply evenly in 2-3 coats, with each coat applied perpendicular to the previous one to ensure no omissions.
  • Pay special attention to details such as corners and pipe roots, applying a thickness of 1-2 mm. Tilt the mortar for better drainage.
  • For multi-layer applications, allow each layer to dry before applying the next, adjusting the interval based on weather conditions.

4. Drying, Curing, and Maintenance

• Drying time: Typically takes a few days to a week, depending on temperature and humidity.
• Maintenance requirements:
  • Ordinary materials should be cured for 2-3 days, keeping the coating moist and avoiding direct sunlight or rapid drying.
  • Polymer emulsion mixed with cement requires curing for more than 14 days; otherwise, the waterproofing effect will be halved.

5. Inspection and Maintenance

• Inspection standards:
  • Visual inspection: Check for cracks, bubbles, or delamination.
  • Water test: Fill with water for 48 hours and observe for leaks.
• Daily maintenance:
  • Avoid scratching the waterproof layer with sharp objects and promptly repair any damage or cracks.
  • Ensure a strong bond with the waterproof layer before laying tiles or decorative materials.
  • Regularly clean the surface to avoid long-term water accumulation and extend the service life.
  • Leak treatment: For small areas, clean the leak site before repairing; for large areas or ineffective repairs, redo the waterproof layer.