Reasons for Water Leakage in Cement Prefabricated Houses

The reasons for water leakage in cement prefabricated houses mainly include four aspects: materials, construction, design, and external force damage, as detailed below:

Material Issues

Poor quality or aging of cement materials is a significant cause of water leakage. After long-term use of cement houses, if the cement itself has quality issues or ages, the waterproof performance will significantly decline. For example, the inclusion of inferior sand and gravel in concrete or the use of expired cement can lead to the breakage of molecular chains in waterproof materials, causing the floor to gradually lose its waterproof capability. Additionally, ordinary concrete does not inherently possess waterproofing functions. If no anti-permeability agent is added, there will be numerous capillary pores inside, and when the water-cement ratio is too high, the seepage of cement paste will become more severe.

Construction Process Issues

Non-standard or lax construction processes are common causes of water leakage. Problems such as improper handling of the waterproof layer and unreasonable proportions of cement mortar directly affect the waterproofing effect. For example, if workers do not use vibrators correctly, air bubbles and voids will remain inside the concrete; if cold joints are left during sequential pouring or water is added arbitrarily to change the mix ratio, cracks will appear on the floor surface; improper curing (such as failing to cover with plastic sheeting in a timely manner) will cause the cement to dehydrate, affecting the setting effect. In rural self-built houses, issues such as uneven mixing of concrete, insufficient cement proportions, and inadequate addition of coarse sand are also relatively common. Furthermore, if steel bars are propped up with stones near the formwork after being tied, and there are also stones on top of the steel bars, cracks can occur due to differences in thermal expansion and contraction; if pipes are not properly fixed or the reserved opening positions are incorrect, and the concrete pouring is not thorough and no waterproofing treatment is done, water leakage can also occur.

Design Flaws

Design flaws are potential causes of water leakage. For example, problems such as the lack of waterproof collars at pipe roots, inadequate reinforcement at internal and external corners, and insufficient roof slope leading to water accumulation can directly damage the waterproof layer. Cutting corners on steel bars leading to support cracking, or the failure to use a level gauge to measure the levelness of rural roofs, with edges built with bricks as guardrails causing an uneven top surface and forming puddles, can also exacerbate the risk of water leakage.

External Force Damage

External force damage is an external诱因 for water leakage. External forces such as wind and rain erosion and plant root growth can damage the waterproof performance of cement houses, and long-term water seepage can also lead to wall cracking. Planting on the rooftops of rural houses, human construction damage, pipe installation damaging the waterproof layer, or quality issues with the waterproof materials themselves can all accelerate the failure of the waterproof layer.