How Many Boards for a 6x6 Deck?
Deck boards to buy
7 12 ft boards
36 square feet, 13 rows of decking, joists 16 inches on center.
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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 length6 ft
- Deck width6 ft
- Board face width5.5 in
- Gap between boards0.25 in
- Board length you buy12 ft
- Joist spacing on center16 in
Deck boards to buy7 12 ft boards
| Deck area | 36 sq ft |
|---|---|
| Board rows across the width | 13 |
| Linear feet of decking | 78 lf |
| Boards at 12 ft | 7 |
| Joists at 16 in on center | 6 |
The material list this produces
| Deck boards, 12 ft | 7 |
|---|---|
| Joists, 6 ft | 6 |
| Joist hangers, each | 12 |
| Deck screws, lb | 2 |
Board length compared
Same deck, four board lengths.
| Board length | Deck boards to buy |
|---|---|
| 8 ft boards | 10 8 ft boards |
| 12 ft boards | 7 12 ft boards |
| 16 ft boards | 5 16 ft boards |
| 20 ft boards | 4 20 ft boards |
What else matters here
Thirteen rows at 6 feet, 78 linear feet, seven 12 foot boards halved with one half spare.
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 6x6 deck?
Seven boards of 5/4 by 6 at 12 feet, cut in half, giving the 13 rows the width needs.
The deck calculator takes any dimensions you like and hands back the same list.