Building a Deck

What must my Deck be built of??

All lumber used must be southern pine grade #2 or better

Lumber grades are bases off of the number of visible defects in the wood that will affect the strength, usefulness, and durability

– Checks– Knots– Stains– Pitch pockets

All hardware must be stainless steel or galvanized– This is so it will not corrode and rot

Inspections Three major inspections are required on all decks

– Footing Required prior to the placing of concrete

– Hole must be 3” bigger on all sides than post Generally 15” x 15”

– Must be below frost line (30” in Maryland)– Must reach virgin soil

– Framing Includes inspections of Ledger, posts, beams, and joists

– Final Includes all rails, stairs, benches, and any other add-ons

All inspections are required by law

Ledgers Ledger must be bolted to house using

carriage or lag bolts with washers, and must be attached to inside header

Bolts and lags must be at least ½” in diameter and placed every 16” on center

Floor joists must be attached to ledger with joist hangers

Siding must be removed where ledger is attached and flashing installed– Flashing must be made of copper, stainless

steel, or uv resistent plastic

Posts

For decks 8’ or lower off the ground posts must be at least 4” x 4”

For decks above 8’ off the ground posts must be at least 6” x 6”

Posts must rest on footers below ground or rest on secured concrete above ground

Diagonal bracing is required for free standing decks

Follow all code charts for post-n-beam sizes and spaces

Beams Beams must be secured to posts by one of the

following two methods– Post caps– Notched post with bolts

Beam Cantilever 2” x 6” prohibited– A cantilever is when the beam overhangs the post

Beam Cantilever 2” x 8” or higher = 2’ maximum All beam splices shall be located over bearing

posts– Splices between posts are prohibited

See all deck/beam span charts for sizing and spacing

Floor Joists All joists must carry

– A live load of at least 40 psf– A dead load of at least 10 psf

Floor joists must be attached to ledger with joist hangers

Cantilever– 2” x 6” = prohibited– 2” x 8” = 2’ maximum– 2” x 10” = 3’ maximum

Centilevered joists must extend back towards the building at least 3 times the cantilever