Deck Construction near you

An attached deck hangs off a ledger bolted to the house band joist. Minnesota's adopted residential code, which reproduces the deck provisions of section R507, requires that ledgers be flashed in accordance with section R703.4 to prevent water from contacting the house band joist, and sets fastener spacing by the span of the deck joists, from roughly 30 inches on center where joists span 6 feet or less down to about 10 inches on center at spans of 16 to 18 feet. The lesson in that table is simple: the longer the joists, the more load each inch of ledger carries, so fastener spacing is not a matter of judgment on site.

Flashing is the other half of the same detail. Water that gets behind an unflashed ledger rots the band joist from the inside, and the deck can look sound from below right up until the fasteners pull through softened wood. Flashing has to be integrated with the house's water-resistive barrier and siding so drainage continues past the ledger rather than stopping at it.

Then there is the pull-away problem. Seattle's building department puts it directly: where a deck connects to the house with a ledger, the ledger must be connected so that it will not pull away during an earthquake, and it points to the prescriptive connection in the adopted residential code or to an engineered design. Lateral load connections do exactly that, tying the deck framing back into the floor system of the house rather than relying on the ledger fasteners alone.

Deck rules come from the residential code as each state and city adopts and amends it, so the thresholds genuinely differ from one address to the next, and quoting a neighbor's experience is a poor guide. Two published examples show the spread.

Seattle requires a construction permit for a deck more than 18 inches above the ground, for a roof deck, or for a deck in an environmentally critical area, and escalates to an addition or alteration permit for decks more than 8 feet above the ground or larger than 750 square feet. Seattle requires a guardrail where a deck is more than 30 inches above adjacent surfaces, with the guard at least 36 inches tall and openings no more than 4 inches, and a handrail on stairs of four or more steps, set 34 to 38 inches above the nosing with a graspable size of 1-1/4 to 2 inches.

Wisconsin's Uniform Dwelling Code draws the lines in different places: guards on all open sides of stairs with more than three risers and on open sides of areas elevated more than 24 inches above the floor or exterior grade, guard openings that block a 4-3/8 inch sphere, a 6 inch sphere limit for the triangle formed by tread, riser and bottom rail, and handrails on flights of more than three risers set 30 to 38 inches above the nosings with at least 1-1/2 inches of clearance from the wall. Wisconsin also requires attached decks to meet its rules for footings, frost penetration, loads, stairs, guards and decay protection.

Structural framing under a deck is almost always preservative-treated softwood, because it is in contact with weather and sometimes soil. The EPA reports that alkaline copper quaternary is currently the most widely used wood preservative for residential applications, and that copper azole is registered for uses ranging from above-ground to marine decking. Both are water-based copper systems, and both are corrosive to ordinary steel, so hardware, hangers and fasteners must be rated for treated lumber.

Surface material is a separate decision. Treated lumber is the least expensive and needs the most upkeep; western red cedar and redwood are naturally decay-resistant and are usually chosen for appearance; wood-plastic composite and cellular PVC trade refinishing for cleaning, and come with manufacturer warranties worth reading before you buy. None of these choices changes the framing or the ledger requirements underneath.

New treated lumber needs to lose its moisture before a finish will penetrate, so plan on a waiting period rather than staining the week the deck is built. After that, a penetrating stain or sealer keeps water out of the surface and slows the graying and checking that sun and rain cause. The EPA notes for treated wood generally that regularly applying a penetrating protective coating, such as an oil-based or water-based stain, may reduce the leaching of chemicals from the wood.

The maintenance that protects the structure is not the finish, though. It is keeping water moving: clearing leaves and debris from between boards and at the house wall, keeping planters and mats from trapping moisture against the decking, and looking at the ledger and its flashing once a year. Composite and PVC surfaces still need the same debris removal even though they never need refinishing.

On LokalMatch you describe the deck you want once, including your ZIP code, the approximate size and how high off the ground it will sit, and deck builders serving that area reach out to you. The professionals pay for the requests they receive, which is what funds the marketplace. LokalMatch never performs the work, never sets or suggests a price, and does not vet, rank or recommend anyone who responds, so the license check, the insurance check and the reference calls are yours to make.

Keep three things when the deck is finished: the permit and the signed-off inspection record, the manufacturer's installation instructions and warranty for the decking and railing, and a written workmanship warranty from the builder. The inspection record in particular is what a future buyer's inspector will ask about, and it is the evidence that the ledger connection was looked at by someone other than the person who built it.