What to do when you discover a leak?
1st You should try to locate the source of the leak
2nd You should make sure to shut off the water and call a plumber, after the plumber has located the source and fixed the problem, you should check to see if the surrounding area shows any signs of dampness or black / greenish spots indicating possible mold. You should never try to open any walls on your own mainly because if there has been a slow leak for any length of time you most likely have mold growing (it only takes 2-3 days for mold to start growing). Mold can grow anywhere however, remember its ideal environment is usually a damp, dark and humid climate.
3rd Should you discover mold you need to contact a restoration company right away! The longer you wait the more damage that is caused and the more expensive the problem becomes. You should not try and mitigate the problem yourself mainly because you run the risk of spreading any possible mold that there is. Depending on the type of mold you’re dealing with, if you do open the walls you can disturb the mold causing it to release spores and toxins into the air making the air quality in your home unhealthy for you and your family. It may also potentially cause an allergic reaction to you or especially any asthmatic people in your home.
4th Remember to choose the right company for you, check to make sure that they are available 24/7, not all issues happen between the hours of 9-5! Check to see if they are licensed and have enough equipment and technicians to properly handle your situation.