Do-it-yourself projects can be fun, but they have to be legal. Your porch design may not need a permit -- some cities give you a pass if the porch is less than 30 inches above grade -- but if it does, it doesn't matter who builds it. Even if you decide to work on it on the weekends and do without a contract, you still need the permit.
TL;DR (Too Long; Didn't Read)
While constructing your own porch will save you money, you'll most likely still have to get a building permit before you can begin the work.
Do It Yourself
Normally, only a licensed contractor can pull a permit for a building or remodeling project. Do-it-yourself projects are an exception: Homeowners in most jurisdictions have the right to do work on their own home. Before you start work, you'll have to go through the permit process just as if you were a professional. That includes submitting plans for the porch to your city or county government, paying permit fees and waiting to see if the plans meet city codes.
Building Requirements
Talk to your city or county about exactly what it takes to get a porch approved. For example, your municipality may require a site plan showing your porch in relation to a scale drawing of your property. Such drawings would also show your house, the property boundaries and the setbacks -- the required space between your porch and your neighbor's house. Your building plans will likely have to detail the porch elevations, floor framing, roof framing -- if you're roofing it over -- and any electrical outlets on the porch.
Potential Problems
No matter how hard you work on the design, it may get rejected. It could be that your front porch extends into the city's right of way, or that the reviewer doesn't think it meets the safety code. Either you pay for an appeals hearing or you redo the design, making the requested changes. If you decide to forge ahead without a permit, you're courting disaster: When the city finds out, it can fine you unless you take the porch down or bring it up to code.
Additional Considerations
If you hire subcontractors to help -- an electrician to run wiring to the porch, for instance -- ask for proof that they have workers' comp insurance to cover any on-the-job injuries. If they're uninsured, you're liable for any injuries that happen while they're working on your house. If you damage your house while you work on the porch, your insurer may not cover the repairs. If you do use a contractor for the project, do not pull the permit even if she says she's really, really busy: That could make you, instead of her, liable for any building-code fines.
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Writer Bio
A graduate of Oberlin College, Fraser Sherman began writing in 1981. Since then he's researched and written newspaper and magazine stories on city government, court cases, business, real estate and finance, the uses of new technologies and film history. Sherman has worked for more than a decade as a newspaper reporter, and his magazine articles have been published in "Newsweek," "Air & Space," "Backpacker" and "Boys' Life." Sherman is also the author of three film reference books, with a fourth currently under way.