How the materials are counted
Fence length (excl. gates) = total length − gates × gate width
Sections per run = ⌈run length ÷ post spacing⌉
Posts = sections + 1 per run + 1 per gate
Rails = sections × rails per section
Pickets = ⌈fence length × 12 ÷ (picket width + gap)⌉
Concrete per post = π × (hole Ø ÷ 2)² × depth − post width² × depth
Concrete bags use QUIKRETE’s published yields (0.375 cu ft per 50 lb bag, 0.60 cu ft per 80 lb bag). Lumber sizes are actual dimensions: a “4×4” post is 3.5 × 3.5 in and a “1×6” picket is 5.5 in wide.
Worked example
150 ft of fence on three sides with one 4 ft gate, posts every 8 ft, two rails, 5.5 in pickets with 0.5 in gaps, 10 × 30 in post holes:
| Fence length excl. gate | 146 ft |
|---|---|
| Sections | 21 |
| Posts | 25 |
| Rails | 42 |
| Pickets | 292 |
| Concrete | 28.8 cu ft = 48 bags of 80 lb |
Call 811 before you dig so underground utilities are marked, and check property lines, permits and HOA rules first.
Frequently asked questions
How far apart should fence posts be?
Eight feet on center is the most common spacing for wood fences, and many plans use 6 ft for taller or heavier fences. Follow your fence design and local code.
How many bags of concrete per fence post?
For a 10 in hole 30 in deep around a 4×4 post, about 1.15 cu ft: two 80 lb bags (0.60 cu ft each).