Quick answers from the same span tables and designer the 16Span planner uses, under your province's Part 9 rules (Ontario unless you pick another) or the US IRC 2021. They run in your browser, instantly.
Which joist sizes span your distance at 12, 16 or 24 in on center, with the margin and maximum cantilever.
Span · spacing · speciesThe beam, how many posts and footings, how far apart, and how big, for a deck of your size and height.
Size · height · attachedAn estimated materials total for your deck and where the money goes, at big-box prices.
Size · height · deckingWhere these numbers come from. The deck's guard and footing depth follow the Ontario Building Code 2024, Part 9, with its article numbers. Joists, beams and posts are sized from the CWC Prescriptive Residential Exterior Wood Deck Span Guide (2016) (incised treated lumber; 1- to 3-ply beams; 4x4 posts up to 6.5 ft, where the plan asks your building department to confirm them, since OBC 9.17.4.1 calls for 6x6); footing diameters use the US AWC DCA 6 table, for reference, since neither NBC Part 9 nor the guide has one for decks. The US reference values are still being checked line by line against the code book. Snow: the calculator doesn't know your town, so it uses Part 9's minimum deck load of 1.9 kPa (40 psf) (OBC 9.4.2.3), the load the guide is for. A town with heavy snow can need more: pick yours below, or have it checked; the full planner looks it up. Treat the result as a starting point and confirm your design with your local building department before you build. OBC 2024's Part 9 is based on NBC 2020. Joist, beam and post tables: Canadian Wood Council, Prescriptive Residential Exterior Wood Deck Span Guide (2016), designed to CSA O86-14 and NBC 2015.
Describe your deck and get a blueprint, a 3D model, a priced materials list, the code check and the build steps.