Unmaintained aging housing stock can lead to health challenges for our communities such as increased exposure to lead, mold and radon. Much of San Mateo County housing stock was built prior to 1978 before the federal government banned the use of lead-based paint. Check out this interactive map to find out the age of the housing stock in your community and visit the San Mateo County Environmental Health’s Healthy Housing program for more information on how to keep your home healthy.