Prefabricated House Foundation

The construction and moisture-proof treatment of prefabricated house foundations should follow scientific standards, with the specific methods outlined below:

I. Construction Process for House Foundations

1. Rebar Framework Installation: Precisely place the prefabricated rebar framework in the excavated foundation pit, ensuring its verticality meets design requirements. The verticality deviation must be controlled within the allowable range specified by the standards to avoid uneven stress on subsequent structures.
2. Concrete Pouring: After wetting the bottom of the foundation pit with water, lay a thick layer of concrete as the foundation bedding. The concrete must be vibrated and compacted to prevent defects such as honeycombs and pitted surfaces, ensuring the foundation's bearing capacity.
3. Stone Leveling: Water the edges of the trench and add stones for leveling, creating a stable foundation surface. The stones should be hard, non-weathered materials with uniform particle sizes to ensure the foundation's flatness.

II. Moisture-Proof Methods for Rural Self-Built House Foundations

1. Laying Moisture-Proof Membranes

• Material Selection: Use high-density polyethylene film (PE film or geotextile), which has high tensile strength and good corrosion resistance, effectively blocking underground moisture.
• Construction Steps:
  • After backfilling and compacting the foundation, lay fine sand and gravel on the surface and compact it to create a flat base layer.
  • Lay the moisture-proof membrane, ensuring an overlap of at least 15 centimeters between membranes. Seal the joints with waterproof tape to prevent moisture penetration.
  • Cut and fit the membrane at corners, and turn it up at least 10 centimeters along the walls to ensure the continuity of the moisture-proof layer.
  • After laying, promptly pour a 10-centimeter-thick concrete bedding or floor to protect the moisture-proof membrane from damage.
• Advantages and Disadvantages: Low cost, simple construction, and short construction period, but limited durability. If the backfill contains sharp objects or the groundwater level is high, or rainwater inflow occurs during the rainy season, the moisture-proof effect may be compromised.
• Precautions: Choose high-quality film, use clean soil for foundation backfilling to avoid puncturing the film, and ensure the film remains intact during construction to maintain its sealing properties.

2. Creating a Prefabricated Panel Suspended Floor

• Moisture-Proof Principle: By creating a space for dryness, leave a 30-50 centimeter cavity between the foundation and the first-floor ground, allowing underground moisture to rise into the cavity and dissipate naturally, preventing it from reaching the first-floor ground.
• Construction Steps: After pouring the ground beams, control the backfill height to be 30-50 centimeters from the ground level and compact the backfill to form stable support.
• Applicable Scenarios: Suitable for areas with high groundwater levels or high humidity, effectively reducing indoor humidity and enhancing living comfort.