Making Prefabricated Cement Houses

Making prefabricated cement houses involves steps such as material preparation, foundation pit treatment, mold installation, structural reinforcement, mold removal and shaping, roof construction, and floor slab pouring. Combining traditional craftsmanship with modern design can enhance house performance.

1. Material Preparation and Mixing
   The first step in making prefabricated cement houses is to prepare the raw materials. Cement and sand should be poured into a mixer in a certain ratio (usually 1:3 to 1:5), and an appropriate amount of water should be added and thoroughly mixed to ensure the mixture is uniform and free of lumps. The strength grade of the cement should be selected according to the house design requirements. The sand should be sieved to remove impurities, and the amount of water should be strictly controlled to avoid affecting the setting effect. The mixing time is usually 3-5 minutes until the mixture takes on a uniform paste-like consistency.

2. Foundation Pit Treatment and Foundation Pouring
   After digging the foundation pit at the selected location, the bottom of the pit should be compacted to ensure a flat foundation with sufficient bearing capacity. Pour the mixed cement into the pit, level and compact it with a small shovel or vibrator to form the foundation layer of the house. The thickness of the foundation layer should be designed according to the geological conditions, usually 15-30 centimeters, to disperse the weight of the house and prevent settlement.

3. Mold Installation and Cement Pouring
   Install prefabricated molds on the foundation layer. The molds should be customized according to the house structure (such as columns and walls) to ensure accurate dimensions. Slowly pour the cement into the molds, and use a vibrating rod or tap the molds to remove air bubbles and avoid internal voids. The pouring process should be carried out in layers, with each layer not exceeding 20 centimeters in thickness, to ensure sufficient cement setting.

4. Structural Reinforcement
   To enhance the earthquake resistance and load-bearing capacity of the house, steel bars or iron rods should be inserted before the cement sets. For example, insert steel bars with a diameter of 12-16 millimeters vertically into the column molds at intervals of no more than 20 centimeters; steel bar meshes can be arranged horizontally in the walls. The steel bars should be tightly combined with the cement to form a reinforced concrete structure, significantly improving the overall strength.

5. Mold Removal and Column Shaping
   After the initial setting of the cement (usually 12-24 hours), the molds can be removed. When removing the molds, avoid damaging the cement surface by gently tapping the edges of the molds with a small hammer to separate them. After removal, the columns or walls should be cured by covering them with wet cloth or spraying water to keep them moist for 7-14 days to promote complete cement hydration and achieve the design strength.

6. Roof Construction and Floor Slab Pouring
   Place the prefabricated roof panels on the columns and fix them with bolts or welding to ensure a firm connection between the roof and the columns. The roof panels should have a drainage slope (usually 2%-5%) reserved to prevent water accumulation. Then, support molds above the roof and pour the floor slab. Use a small scraper to level the cement, and after removing the molds, a flat floor slab is formed. The thickness of the floor slab should be designed according to the span, generally 10-15 centimeters.

Modern Improvement Directions: Some cases adopt a modular design, decomposing the house into standard modules (such as walls and floor slabs) for prefabrication in the factory and on-site assembly, shortening the construction period and reducing errors. In addition, the wire embedding technology can embed electrical conduits and water pipes into the cement before pouring, avoiding later slotting that may damage the structure and improving the functionality and safety of the house.