You are likely to find this post helpful in regards to defects. Construction defects are common, though most defects are minor and fairly inconsequential. Specifically you will be interested in how to minimize construction defects. There are a few proactive measures everyone can take to decrease the chance of encountering a defect in construction.
1. Review the Contract Terms and Policy Coverage
2. Implement Quality Control Programs
3. Act Quickly
I hope that helps!