Generally, when homebuyers have their homes built from the ground up they use construction loans followed by permanent mortgages. Fortunately, a mortgage product called a "construction-to-perm" loan is available that doesn't require two separate loans complete with separate closing costs. While a construction-to-perm loan might seem likely only for more well-to-do homebuyers, the Federal Housing Administration actually does offer its own version. An FHA one-time close mortgage truly allows you to have your home built and financed under one loan.
The same county level maximum lending limits FHA applies to all its mortgages also apply to its one-time close home loans. Nationally, the FHA loan limit is $417,000, though limits in high-cost counties are as high as $729,250. FHA one-time close mortgages involve several stages that lenders must handle and they can be a bit complex. Many FHA-approved lenders choose not to offer the agency's one-time close home loan product or will limit it to manufactured or modular homes only.
Web Reference: http://USAConstructionLoans.com