What can happen if the building is not waterproof? Bad waterproofing creates serious risks to the integrity of the building. Construction projects may suffer structural damage due to poor or insufficient waterproofing of the roof and concrete. Cracks in the foundation or joints exposing to water can lead to more serious structural problems. These include leaks, spalling and deterioration. Mold growth is also a common waterproofing problem that is difficult to correct. If the building is built of wood or has wooden furniture, moisture from the penetration of water will lead to rotting or delamination of wood. Mold spores are also a health hazard. Exposure to this can lead to allergies, asthma, irritation and fungal infections. After studying several cases, WHO issued a report on this issue, which states that water leakage in buildings poses a health hazard, and about 50 terrible diseases are caused by damp stains on the wall. Practice has established that minor problems associated with moisture, seepage and leakage can be effectively resolved and prevented by using good quality materials by skilled craftsmen.