ContractorHandbook

How Many Boards for a 12x16 Deck?

Deck boards to buy

26 16 ft boards

192 square feet, boards running the 16 foot direction, joists 16 inches on center.

It does not stop at a number.

When the figures look right, the deck material list downloads as a real PDF with your business details on it, built inside your own browser. Nothing you type is uploaded anywhere.

boardgap betweenboardsdeck width, ftwidth / (board + gap) = rows, rows x length = linear feet
Decking is bought in linear feet and laid in rows, and the gap between boards is what sets how many rows fit. A quarter inch gap across a twelve foot width is most of an extra board, which is the difference between one trip and two.

How that number is worked out

These are the figures this page was built with and every line the calculator produces from them. Change anything above and all of it moves.

  • Deck length16 ft
  • Deck width12 ft
  • Board face width5.5 in
  • Gap between boards0.25 in
  • Board length you buy16 ft
  • Joist spacing on center16 in

Deck boards to buy26 16 ft boards

Deck area192 sq ft
Board rows across the width26
Linear feet of decking416 lf
Boards at 16 ft26
Joists at 16 in on center13

The material list this produces

Deck boards, 16 ft26
Joists, 12 ft13
Joist hangers, each26
Deck screws, lb6

Board length compared

Same deck, four board lengths. Longer boards mean fewer end joints and more offcut risk.

Board lengthDeck boards to buy
8 ft boards52 8 ft boards
12 ft boards35 12 ft boards
16 ft boards26 16 ft boards
20 ft boards21 20 ft boards

What else matters here

Running the boards the 16 foot way is what makes this deck cheap to build: every row is one board, so there are no butt joints anywhere in the field, and a butt joint is both the ugliest part of a deck and the part that rots first.

That only works if you can actually buy straight 16 foot decking. Inspect it on the rack rather than at the till, because a crowned 16 foot board is a fight for the whole row and a 12 foot board is not.

Thirteen joists at 16 inch centers spans the 12 foot direction. Check the span table for the species and size you are using before you order: southern yellow pine 2x8 and Douglas fir 2x8 do not span the same distance, and neither does anything that has been sitting wet.

What this calculator assumes

  • A nominal 2x6 board is 5.5 inches of actual face. Nominal sizes are not real sizes, which is where most deck orders go wrong.
  • Joist count is the span across the deck width at the spacing given, plus one for the last joist.
  • Waste is not added. Add 5 to 10 percent if the deck is not a plain rectangle.

Questions people ask

How many deck boards for a 12x16 deck?

About 26 boards of 5/4 by 6 at 16 feet, which is 416 linear feet across 26 rows.

Which way should deck boards run?

Perpendicular to the joists, which usually means parallel to the house. On a 12 by 16 deck running them the 16 foot way removes every butt joint.

How many screws for a 12x16 deck?

About 6 pounds, based on two screws per joist per board. Hidden fasteners use a different count entirely, so check the clip manufacturer's coverage.

Different numbers?

The deck calculator takes any dimensions you like and hands back the same list.

Other common sizes