Dampness in Prefabricated Houses

The issue of dampness in prefabricated houses can be comprehensively addressed through scientific design, standardized construction, and regular maintenance. Specific measures are as follows:

I. Damp-Proof Design and Material Selection

1. Material Optimization: Utilize waterproof cement (containing hydrophobic components), polymer-modified mortar (enhancing adhesion and flexibility), and damp-proof membranes (isolating groundwater). For example, adding a damp-proofing agent to cement can increase its density, reduce porosity, and effectively block moisture intrusion.
2. Structural Protection: The design of walls and roofs should emphasize slope to ensure rapid drainage of rainwater and prevent water accumulation and penetration. Indoor floors can adopt damp-proof cushions or elevated designs (such as prefabricated slab elevated floors), allowing ground moisture to dissipate through a 30-50 cm cavity and preventing moisture from rising to the ground floor.

II. Damp-Proof Measures During Construction

1. Foundation Treatment: Ensure the foundation is higher than the surrounding ground, and install drainage ditches or waterproof layers (such as laying damp-proof membranes) to prevent groundwater from rising. After backfilling the foundation, level it with fine sand and gravel, then cover it with a damp-proof membrane (thickness ≥ 0.15 mm), and finally pour a concrete垫层 (sub-base).
2. Joint Sealing: When assembling prefabricated components, fill the joints with specialized sealing materials to prevent moisture from entering through gaps.
3. Construction Environment Control: Store prefabricated components indoors and seal windows to prevent rainwater from increasing air humidity; cover with waterproof cloth when stored outdoors. Avoid construction on rainy days. If prefabricated floor slabs become damp, immediately relocate them to a dry and ventilated area, use large-scale moisture-absorbing dryers for treatment, or sandblast damaged areas and reapply anti-permeability waterproof coatings.

III. Maintenance and Inspection

1. Regular Inspection and Repair: Check whether the coatings on walls, floors, and roofs are intact, and promptly repair cracks or peeling areas to prevent moisture penetration.
2. Ventilation Management: Maintain indoor ventilation by installing ventilation equipment or regularly opening windows; use dehumidifiers during humid seasons to assist in controlling humidity and prevent moisture accumulation.

IV. Comparison of Damp-Proof Solutions for Rural Self-Built Houses

1. Laying Damp-Proof Membranes: Low cost (approximately one to two thousand yuan for a house), simple construction, but limited durability, prone to being punctured by sharp stones, and effectiveness may be compromised with high groundwater levels.
2. Prefabricated Slab Elevated Floors: Exchange space for dryness, with more stable damp-proofing effects, but ensure the backfill is compacted to prevent cavity collapse.

Precautions: Ensure the quality of damp-proof membranes and avoid using inferior plastic films; replace severely damp prefabricated floor slabs and strictly prohibit the use of substandard materials.