A. Almost, with a few exceptions, depending on where you are building your house. All building departments will require a site plan to show where the house will sit on your property. You might also need beams sized to accommodate roof loads specific to your region. Your home builder can usually help you with this. If you are not connecting to a sewer system, you also need a septic design attached to your application. And many areas now require compliance with local energy codes, which is normally a simple form you fill out and attach to your application.

In some regions, you also need to ensure that your house plans are in compliance with local codes. Some areas of North America have very strict engineering requirements. For example, earthquake-prone areas of California and the Pacific Coast, hurricane risk areas of the Florida, Gulf, and Carolina coasts, as well as New York, New Jersey, Nevada, and parts of Illinois require review by a local professional. If you are building in these areas, you will most likely need to hire a state-licensed structural engineer to analyze the design and provide additional drawings and calculations required by your building department. If you aren't sure, building departments typically can give you a handout, listing all of the items they require to obtain a building permit.

Additionally, stock plans do not have a professional stamp affixed. If your building department requires one, they will accept only a stamp from a state-licensed professional where you plan to build. In this case, you will need to have your house plans reviewed and stamped by a local engineer or architect.

Please keep in mind that it is the owner's full responsibility to ensure that any house plan purchased meets all local and state building requirements.