Identifying and Preventing Common Cracks in Newly Built Homes
Cracks: Structural vs. Non-Structural
Not all cracks indicate a structural failure. It is essential to differentiate between minor, non-structural cracks (usually hairline and cosmetic) and wide, structural cracks that indicate a severe foundation or load-bearing problem.
Common Crack Causes and Prevention
- **Plastic Shrinkage Cracks:** Hairline cracks appearing on concrete slabs (e.g., floors) within hours of pouring. **Prevention:** Proper curing (keeping the surface wet) and ensuring the concrete mix is not overly dry or wet.
- **Settlement Cracks:** Diagonal cracks (usually wider at the top) appearing on walls or near windows/doors. **Prevention:** These are serious. Ensure the **sub-soil is properly compacted** before pouring the foundation and that the foundation depth is adequate.
- **Thermal Cracks:** Fine cracks appearing in plaster/render. **Prevention:** Proper curing of plasterwork, applying an adequate mix (correct sand-to-cement ratio), and using a bonding agent between the wall and plaster.
If you observe a crack wider than $3\text{mm}$ or one that extends diagonally across a load-bearing wall, immediately consult a professional structural engineer.