Shadow box fences put pickets on both sides of the rails with a gap on each side narrower than a picket.
How pickets are counted
Side by side: pickets = (length + gap) ÷ (picket width + gap), rounded up. Board on board: 2 × length ÷ (2 × width − 2 × overlap). Shadow box: 2 × length ÷ (width + gap).
Example: 8 ft of 5.5 in pickets, shadow box, takes 24 pickets.
Pickets needed at a glance
Worked out with the same settings as the calculator above, changing only the length.
| Length | Pickets | Spacing |
|---|---|---|
| 8 ft | 24 | 8.50 in |
| 50 ft | 142 | 8.50 in |
| 100 ft | 284 | 8.50 in |
| 150 ft | 424 | 8.50 in |
Nominal and actual sizes
| Nominal | Actual (dry) |
|---|---|
| 1 in | ¾ in |
| 5/4 in | 1 in |
| 2 in | 1½ in |
| 4 in | 3½ in |
| 6 in | 5½ in |
| 8 in | 7¼ in |
| 10 in | 9¼ in |
| 12 in | 11¼ in |
Under the American Softwood Lumber Standard (PS 20).
Common questions
How many pickets are in an 8 ft section?
With 5½ in pickets butted together, 96 ÷ 5.5 = 17.5, so 18 pickets. With 3½ in pickets and 2½ in gaps, 17.
What size are fence pickets?
Common pickets are nominal 1×4 (3½ in wide) and 1×6 (5½ in wide). Many cedar pickets are 5/8 in thick rather than ¾ in.
How much extra should I buy?
Buy 5 to 10% extra for split or warped boards and cuts around gates and posts.
Sources
- NIST, American Softwood Lumber Standard (PS 20): https://www.nist.gov/standardsgov/voluntary-product-standards-program