Does the Roof of Cement Prefabricated Houses Leak?

The roofs of cement prefabricated houses are prone to leaking, which is a relatively common defect. The specific reasons and situations are as follows:

Structural Characteristics Leading to Easy Leakage

The roofs of cement prefabricated houses are usually composed of multiple independent prefabricated panels joined together. During the joining process, tiny gaps inevitably exist between the panels. Although these gaps may seem insignificant, they become channels for rainwater penetration during rainy weather. Rainwater flows down along the roof's slope and can easily seep into the house through these gaps when encountered. Moreover, over time, due to factors such as the natural settlement of the house and thermal expansion and contraction caused by temperature changes, these gaps may further widen, exacerbating the leakage situation.

Impact on Steel Reinforcement Corrosion

After rainwater seeps into the house through the gaps, it directly comes into contact with the steel reinforcement structure in the roof. Steel reinforcement is prone to rusting after being exposed to rainwater for a long time. Rusting of steel reinforcement causes its volume to expand, which in turn exerts pressure on the surrounding cement structure, leading to cracks or even spalling of the cement. This not only further aggravates the roof leakage problem but also affects the overall structural safety and durability of the house, shortening its service life.

Common Situation in Rural Self-built Houses

The use of prefabricated panels as roofs is relatively common in rural self-built houses. However, relevant data shows that among this type of house, 8 out of 10 experience rain leakage. This indicates that the roof leakage problem of cement prefabricated houses is highly prevalent in the field of rural self-built houses. Moreover, even when waterproofing treatment is carried out, the probability of rain leakage is relatively high due to the special structure of the prefabricated panel roof. This may be because the waterproofing material is difficult to completely fill the gaps between the panels, or the waterproof layer is damaged during long-term use due to external factors, resulting in poor waterproofing performance.