National Center for Healthy HousingThe Healthy Housing Challenge is a partnership between Rebuilding Together and the National Center for Healthy Housing (NCHH), the leading expert in healthy homes, with funding support from the Wells Fargo Housing Foundation and Freddie Mac. Each year, Rebuilding Together’s 200 affiliates mobilize 100,000 volunteers to make repairs at no charge to the homes of low-income seniors, veterans, the disabled, and families with children.