Estimating 100 ft of 6 ft Privacy Fence, End to End
The same 100 ft fence as the fence calculator’s worked example, taken from string line to final picket — including the quantities the calculator does not cover, like gravel and gate hardware.
Calculators used
The project
100 ft of 6 ft solid-board privacy fence with one 4 ft gate, posts at 8 ft centres, three rails per section, 1x6 pickets butted tight. These are the defaults of the fence calculator, so every count below can be reproduced with one click of it.
The counts, and where each comes from
| Line | Count | Arithmetic |
|---|---|---|
| Fence line | 96 ft | 100 − 4 ft gate |
| Sections | 12 | 96 ÷ 8, rounded up |
| Posts (4x4, 8 ft) | 14 | 12 + 1 = 13, plus 1 for the gate |
| Rails (2x4, 8 ft) | 36 | 12 sections × 3 |
| Pickets (1x6, 6 ft) | 210 | 96 ft = 1,152 in ÷ 5.5 in face |
| Concrete (80 lb bags) | 30 | 10 in holes, 30 in deep, minus post volume, +10% |
| Gravel (0.5 cu ft bags) | ~7 | 4–6 in in each of 14 holes |
The post count is the classic trap: a fence needs one more post than it has sections, plus one per gate. And note what the picket line assumes — butted tight, because wet pressure-treated boards shrink gaps open on their own. Buy a bundle margin anyway; a 5% cull rate for warped and split pickets is normal, so 220 boards is the safe order.
Day 0 — layout
Run a string line, mark post centres every 8 ft, and square any corner with the 3-4-5 triangle — the layout guide walks through it. Call the utility locate line (811 in the US) before this day is over, because the holes come next.
Day 1 — holes and posts
Fourteen holes, 10 in wide and 30 in deep — the one-third-of-height rule for a 6 ft fence, deeper if your frost line demands it. A rented one-person auger turns this from a two-day grind into a morning; clay or rocky ground justifies the two-person machine. Then: 4–6 in of gravel in the bottom of each hole, post in, concrete around, crowned at grade, plumb checked twice. An 8 ft post buried 30 in stands 5 ft 6 in proud, and the pickets run above the post tops to the full 6 ft line.
Day 2 or 3 — rails and pickets, after the concrete says so
Concrete needs 24 to 48 hours before the posts can take rail loads — rushing this is how fences end up wavy. Hang three rails per section, then run pickets to a string line at the top, checking plumb every fourth board. The gate hangs last, on the gate post you sensibly set one size deeper: hinges, latch and a diagonal brace kit are the hardware lines the lumber list above does not include.
Pricing it
Take the table to a lumber yard as-is. Fence cost scales almost linearly with length, so a per-foot quote is easy to sanity-check: everything in the list divided by 100 ft is your materials cost per foot — useful when comparing against contractor bids, which bundle labour at roughly half to two-thirds of the total.
Frequently asked questions
How long does 100 ft of fence take to build?
A realistic DIY schedule is three days: layout and hole digging, setting posts in concrete, then rails and pickets after the concrete has had 24 to 48 hours. An auger rental on day one is what keeps it to three.
Should fence pickets touch the ground?
No — keep them an inch or two clear. Ground contact wicks moisture into the end grain and rots pickets from the bottom; a string line at the top and a spacer block at the bottom keeps the run straight and dry.
How many pickets do I need per foot of fence?
A 1x6 picket has a 5.5 inch face, so butted tight you need about 2.2 pickets per foot of fence line. With a typical 5 percent cull for warped boards, order about 2.3 per foot.