ContractorHandbook

How Many Boards for a 6x8 Deck?

Deck boards to buy

13 8 ft boards

48 square feet, 13 rows running the 8 foot way, 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 length8 ft
  • Deck width6 ft
  • Board face width5.5 in
  • Gap between boards0.25 in
  • Board length you buy8 ft
  • Joist spacing on center16 in

Deck boards to buy13 8 ft boards

Deck area48 sq ft
Board rows across the width13
Linear feet of decking104 lf
Boards at 8 ft13
Joists at 16 in on center7

The material list this produces

Deck boards, 8 ft13
Joists, 6 ft7
Joist hangers, each14
Deck screws, lb2

Board length compared

Same deck, four board lengths.

Board lengthDeck boards to buy
8 ft boards13 8 ft boards
12 ft boards9 12 ft boards
16 ft boards7 16 ft boards
20 ft boards6 20 ft boards

What else matters here

Thirteen rows, each a single 8 foot board, 104 linear feet in total. No cuts on the field boards.

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 boards for a 6x8 deck?

Thirteen boards of 5/4 by 6 at 8 feet, one per row, no cutting on the field.

Different numbers?

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

Other common sizes