Deck and porch permits — what every county requires

A deck is one of the most popular weekend projects in the US, and it is also one of the most commonly skipped permits. The skip is a mistake. Decks fail every year — sometimes catastrophically — and almost every failure traces back to one of a handful of detail issues that an inspection would have caught. When a permit is required. Most jurisdictions require a permit for any deck more than 30 inches above grade at any point. Many also require a permit for decks attached to the house regardless of height, because the ledger connection to the house framing is a structural element. Floating decks well below 30 inches and detached from the house are often exempt, but check. Application package. A site plan showing the deck location relative to property lines, a framing plan showing joist size and spacing, beam size and post locations, a lateral connection detail, the ledger connection detail, and the guard and stair details. For decks over a certain size, some counties require an engineer's stamp; most accept prescriptive details from the residential code for typical residential decks. Typical fees. Deck permits are usually flat-fee or based on valuation, in the range of $120 to $350 for a standard residential deck. Inspection sequence. Footing inspection (before the concrete is poured), framing inspection (before the decking is installed), and final inspection. What inspectors actually check. Footing depth (must extend below the local frost line in cold climates), the connection between the post and the footing, the connection between the beam and the post, the ledger connection to the house (lag screws or through-bolts in the correct pattern, with flashing), joist hangers nailed correctly, lateral load connectors where required, and guard and stair construction (4-inch sphere rule for guards, 4-inch riser variation rule for stairs). The ledger and the lateral connectors are the two details that are most commonly wrong on owner-built decks and are also the two most safety-critical. Pulling a permit means an inspector will catch them before they fail.