Start with your deck size and get boards, joists, rim and screws on one list. Use the deck joist and footing pages for the code-driven sizing.
How it works
Boards are the rows across the depth multiplied by the run with 10% added. Joists are the deck length ÷ spacing, plus one.
Before you order
- Plan board lengths so butt joints land on joists and stagger across the deck.
- Double up joists where boards meet at a break line.
- Pull a permit first, since inspectors check the ledger and footings as well as the surface.
Common questions
How many boards does a 12 × 16 deck need?
About 28 rows of 16 foot boards at 5.5 inch width, so roughly 30 with waste.
Do I need a permit for a deck?
Most areas require one for attached or raised decks. Ask your building department.