Fence calculator

Every line shows the quantity to buy and how StudSheet got it: the spacing, the waste and the package size, so you can check it before the supply house or the quote.

In Canada (30.48 m wood fence, 1.83 m tall)

Set to Canada, the Sheet works the job out again for Ontario: metric sizes, bag sizes, the frost depth and the code notes. It doesn't just convert feet to meters. The first lines:

• 17 posts, Pressure-treated 4×4 post: 2 end, 2 corner and 11 line posts, + 2 gate posts: 1.83 m above the ground + 1.07 m in it.
• 67 bags, Fast-setting concrete mix, 30 kg: 0.75 m³ around 17 posts (254 mm holes, filled to 51 mm below the ground), +10% for uneven holes; 30 kg bag ≈ 0.012 m³ (Quikrete) — about 3.5 bags a post. Regular mix in a tub costs about half as much per post on a job this size.
• 10 bags, Drainage stone, 19 mm clean: 152 mm in the bottom of every hole so water drains away from the post end: 0.13 m³.
• 45 boards, Pressure-treated 2×4: 3 rows of rails × 15 bays, one 2.44 m board per bay, ends meeting on the posts.
• 3 boards, Pressure-treated 2×4: 1 gate leaf 1.22 m wide: 3 rails and a diagonal brace each.
• 230 boards, Treated fence pickets: 30.48 m of fence and gates ÷ 140 mm boards side by side = 219, +5% for splits and culls.

1. Call 811 (NJ One Call) at least 3 full business days ahead and wait for the utility markings.
2. Find your property line (the pins or a survey), check the height limit and the side that must face out, and talk to the neighbors.
3. Stake the ends and corners and pull a string line between them; mark a post about every 8′, and leave 4′ openings between gate posts.
4. Dig 17 holes 10″ wide: 42″ deep, 48″ for the gate posts.
5. Put 6″ of gravel in each hole; set the end and corner posts plumb, 36″ in the ground, then pull a string between them at the top for the line posts.
6. Set each post plumb and pour the fast-setting mix in dry, about 3.6 bags a hole, then add the water; crown the top so water runs off.
7. Let the concrete set before any rails or weight go on: about 4 hours for fast-setting mix, a day for regular.
8. Cut the posts to height with a level line and screw on the rails: 3 rows of 2×4, two 3″ screws at each end.
9. Nail the boards on tight side by side, 2″ off the ground, two nails at every rail; check plumb every few boards.
10. Build each gate on a Z-frame — rails and a diagonal brace running down to the hinge side — then hang it with 3 hinges, ½″ clear at the latch side; add the latch and the anti-sag kit.
11. Cap the posts.
12. Let the treated wood dry until water soaks in instead of beading, often 1–3 months; then stain both sides.

Must-have tools first, then the ones that help and the ones to rent for the day.

Mistakes that cost a callback or a second trip

• Building on the wrong side of the line: A fence over the property line can be ordered moved at your cost. Find the pins or get a survey first.
• Posts set too shallow or out of plumb: They lean in the wind and heave in frost. 36″ in the ground here, plumb both ways before the concrete sets.
• Water sitting at the post: Concrete flared over the ground gives frost something to lift, and a cupped top holds water against the wood. Gravel under the post, concrete crowned just below the ground.
• Boards touching the ground: They wick water and rot. Keep them 2″ up; a straight 2×4 on the ground is an easy spacer.
• A gate brace running the wrong way: The diagonal must run from the bottom of the hinge side up to the latch side, or the gate sags.

What the calculator assumes

• Posts about 8′ on center: one per bay, + one per gate and one per two free ends; each corner or gate adds a short bay, because a stretch rarely ends on an even bay.
• Holes: ½ of the height above ground, at least 2 ft (Quikrete), + 6″ of gravel; gate posts 6″ deeper. To the frost depth where it’s known, up to 4 ft.
• Concrete to 2″ below the ground, +10% for uneven holes: 50 lb fast-setting ≈ 0.375 cu ft, 80 lb regular ≈ 0.6 cu ft (Quikrete). Fast-setting mix takes rails after about 4 hours.
• Boards +5% for splits and culls; board-on-board overlaps 1″ each side, shadowbox ¾″. Rails: 2 rows up to 4′ 6″, 3 up to 6′ 6″, 4 above.
• Fasteners: hot-dip galvanized or stainless with treated lumber (the treatment eats plain steel), stainless with cedar.

The Sheet sets its code notes for the job's state or province. These are New Jersey's and Ontario's; the code reference has more. Always confirm with your building department.

• Call 811 first — it’s the law: In New Jersey, call 811 (NJ One Call) at least 3 full business days before digging. Free. Wait for the utility markings.
• Know your property line: A fence over the line can be ordered removed. Find the property pins or get a survey, and set the fence inside your line unless you and your neighbor agree in writing. Many towns and HOAs want the finished side facing out.
• Post depth: Holes 42″ deep (36″ of post in the ground, on 6″ of gravel), gate posts 48″. Frost line: 36″ in Mercer/Middlesex and north, 30″ south. Confirm with your building department. These holes reach below it.
• Height limits come from zoning: New Jersey towns set fence heights in their zoning ordinance — often about 4 ft in front yards and 6 ft behind. Ask your town. Many towns want the finished side facing the neighbor or the street.
• Ask your town: Most New Jersey towns want a zoning permit for a fence, and a pool barrier needs a construction permit and inspection. Ask your town’s zoning officer before you dig.
• Click Before You Dig: Before you dig, request a free utility locate from Ontario Dig Authority (ontariodigauthority.ca) at least 5 business days ahead, and wait for the markings.
• Fence by-laws set the height: Your municipality’s fence by-law sets the heights: Toronto allows 2.0 m in back and side yards and 1.2 m in a front yard near the street; Ottawa 2.13 m in back and side yards and 1.0 m in front. Confirm with your building department.
• Usually no building permit: Most Canadian cities need no building permit for a fence; the fence by-law sets the heights and where it can go. Ask your municipality’s building department if unsure.

What materials do I need to build a wood fence?

For the worked example, a 100′ wood fence, 6′ tall, the Sheet counts 12 lines with waste included, starting with pressure-treated 4×4 post (17 posts), fast-setting concrete mix, 50 lb (67 bags), drainage stone, ¾″ clean (10 bags), pressure-treated 2×4 (45 boards). Each line's math is in the table above. Put in your own sizes in the fence calculator and every line is counted again.

How long does it take to build a wood fence, and can I do it myself?

About 37 to 58 hours for the worked example, in 12 steps. StudSheet stamps it DIY OK: you can do this.

What tools do I need to build a wood fence?

25 in all. The must-haves start with tape measure (25 ft), mason's line + stakes, line level, post level, 4-ft level, post-hole digger. On the Sheet you mark each one as owned, to buy or to rent.

Stuck while you build a wood fence? Ask in the Fences group of the StudSheet community with this Sheet attached. Homeowners who've done it and verified pros answer, and anyone can read it.

• Decks and fences for contractors: run this takeoff at your own prices, send the estimate, and get it signed and the deposit paid.
• Build deck or porch stairs (Stairs for a 3′ rise): Lay out and cut stringers, treads, risers and the landing — to code.
• Deck or balcony (16′ × 12′ deck): Footings, posts, beams, joists and decking for a deck, or a balcony on posts, with the railing it needs.
• Railings and guards (12′ wood railing): Wood, aluminum, steel, glass or cable railings for decks, balconies, porches and stairs: posts, panels, hardware and the height rules.
• Build a raised garden bed (8′ × 4′ raised bed): Boards cut from the fewest pieces, corner posts, screws, a liner against weeds or gophers, and the soil by the bag or by the yard.
• All 45 Sheets, across 16 trades.
• Code reference: frost depths, guard heights, stairs, retaining walls.