Your Result Explained: Exact Takeoff Breakdown
Enclosing an entire suburban three-sided backyard typically requires right around 200 linear feet of 6-foot privacy fencing plus two gate openings—one 4-foot walk gate on the side of the house and one 5-foot or 8-foot mower access gate on the opposite side. Adding two gates to a 200-foot run changes your post and footing counts because each gate break introduces an extra hinge/latch post that must be anchored in concrete.
Dividing 200 linear feet by 8-foot post spacing gives 25 bays. A continuous 25-bay fence requires 26 line/corner posts, and adding 2 gates adds 2 extra dedicated gate posts for a total of 28 posts (4×4×8'). Three horizontal 2×4 rails per bay across 25 bays equals 75 net rails—or 83 rails with a 10% waste buffer (which also supplies extra 2×4 framing for your two gates). Covering 200 linear feet (2,400 inches) with 5.5-inch 1×6 dog-ear pickets at zero gap requires 437 net pickets, or 480 pickets with 10% culling waste, fastened with 2,880 exterior screws. Setting all 28 posts in 10" × 30" footings takes 35.45 cubic feet (1.31 cubic yards) of concrete: 60 bags of 80 lb mix (or 79 bags of 60 lb mix).
Sixty 80-lb concrete bags weigh 4,800 lbs (2.40 tons)—more than a full pallet of concrete—and 480 pickets, 83 rails, and 28 posts weigh another ~3,200 lbs. Order boom-truck delivery from a local building supply yard rather than making four trips with a pickup truck.
Step-by-Step Math for a 200 Ft Backyard Fence With 2 Gates
Calculating bays, 28 posts (including 2 gates), 3-rail stringers, 1×6 privacy pickets, screws, and 10"×30" concrete footings with 10% waste.
- Calculate 8 ft bays: ⌈200 ft ÷ 8 ft⌉ = 25 bays.
- Compute total 4×4 posts (including 2 gates): 25 bays + 1 end post + 2 gate posts = 28 posts.
- Compute 2×4 horizontal rails (3 rails/bay): 25 × 3 = 75 net × 1.10 = 83 rails.
- Compute 1×6 pickets (5.5" width, 0" gap): (200 ft × 12) ÷ 5.5 in = 436.36 net × 1.10 = 480 pickets.
- Calculate fasteners (2 screws × 3 rails): 480 pickets × 6 = 2,880 exterior screws (or ring-shank nails).
- Compute concrete for 28 holes (10" dia × 30" deep): 28 × 1.1509 cu ft × 1.10 = 35.45 cu ft (1.31 cu yds).
- Convert concrete to bags: ⌈35.45 cu ft ÷ 0.60⌉ = 60 bags of 80 lb mix (or 79 bags of 60 lb mix).
Bottom Line: Order 28 (4×4×8') posts, 83 (2×4×8') rails, 480 (1×6×6') pickets, 2,880 exterior screws, 2 heavy-duty gate hardware kits, and 60 bags of 80 lb concrete.
How This Scenario Is Calculated
We divide 200 linear feet by 8 ft post spacing to get 25 bays, add 1 terminal post plus 2 extra gate posts to reach 28 posts, and multiply 25 bays by 3 rails per bay (+10% waste) to obtain 83 horizontal 2×4 rails.
Dividing 2,400 linear inches by 5.5-inch actual picket width gives 436.36 net pickets, which multiplies by 1.10 for 10% culling waste to equal 480 pickets. Across 28 post holes (10" diameter × 30" deep, holding 1.1509 net cu ft each after post displacement), total concrete volume with 10% waste is 35.45 cubic feet—requiring 60 bags of 80 lb concrete.
Bays = ⌈Length ÷ Post Spacing⌉ | Posts = Bays + 1 + Gates | Rails = ⌈Bays × Rails/Bay × (1 + Waste%)⌉ Pickets = ⌈[(Length Ft × 12) ÷ (Actual Picket Width In + Gap In)] × (1 + Waste%)⌉ Hole Concrete (ft³) = [π × (Dia/24)² − (3.5/12)²] × (Depth/12) × Posts × (1 + Waste%) Project-Specific Tips & Common Mistakes
Rent a Towable Hydraulic One-Man Auger for 28 Post Holes
Digging 28 ten-inch holes 30 inches deep with a manual clamshell digger or a rigid handheld 2-stroke auger in clay or rocky soil is brutal on wrists and backs. Rent a self-propelled hydraulic auger for $95/day to bore all 28 holes in under 2 hours.
Upgrade the 2 Gate Hinge Posts to 4×6 or 6×6 Lumber
Out of your 28 posts, substitute two 4×6×8' or 6×6×8' pressure-treated posts for the hinge sides of your two gates, and frame each gate with a compression diagonal 2×4 brace running from the bottom hinge corner up to the top latch corner so the gates never sag.
Use a Pneumatic Framing/Siding Nailer for 2,880 Fasteners
Driving 2,880 deck screws by hand with an impact driver takes a full day. Load a pneumatic 15-degree coil siding nailer with 1-7/8" or 2" hot-dipped galvanized ring-shank nails to hang all 480 pickets in a single afternoon.
Mistake Forgetting to add extra posts and concrete bags for the 2 gates
Recommended Fix: Every gate opening breaks a standard 8-foot bay into a narrower gate opening plus a stub panel, requiring an extra dedicated post and 2+ extra bags of concrete per gate.
Mistake Installing a tension cable instead of a rigid compression diagonal brace on wood gates
Recommended Fix: Wood gate frames stay square longest when a 2×4 diagonal brace is mitered tightly from the bottom-hinge corner up to the top-latch rail (in compression), or when built onto a welded steel no-sag gate frame kit.
Reference Coverage Table (Normal-Weight Portland Cement Concrete)
Compare how coverage changes across common depths for Normal-Weight Portland Cement Concrete (default planning density 4000 lbs/yd³):
| Depth | 1 Cubic Yard Covers | 1 Ton Covers | Yards / 100 sq ft | Tons / 100 sq ft | Bags (0.6 ft³) / 100 sq ft |
|---|---|---|---|---|---|
| 24 in | 13.5 sq ft | 6.8 sq ft | 7.41 yd³ | 14.82 tons | 334 bags |
| 30 in Active | 10.8 sq ft | 5.4 sq ft | 9.26 yd³ | 18.52 tons | 417 bags |
| 36 in | 9 sq ft | 4.5 sq ft | 11.11 yd³ | 22.22 tons | 500 bags |
| 42 in | 7.7 sq ft | 3.9 sq ft | 12.96 yd³ | 25.92 tons | 584 bags |
Reference Source: ACI 302.1R / ACI 318 (145–150 lbs/ft³) & Quikrete No. 1101 Technical Data Sheet.
Frequently Asked Questions
How many fence posts do I need for 200 feet of fence with 2 gates?
At 8-foot spacing, 200 linear feet equals 25 bays, which takes 26 standard posts plus 2 extra gate posts—totaling 28 posts.
How many 1×6 pickets do I need for a 200-foot privacy fence?
With zero gap between 5.5-inch actual width pickets, 200 feet requires 437 net pickets, or 480 pickets when including a 10% allowance for culling warped boards (note: pickets covering the two gates are already included in the 200 linear feet).
How many bags of 80 lb concrete are needed for 28 fence posts?
Twenty-eight posts in 10-inch diameter by 30-inch deep holes require 35.45 cubic feet of concrete (with 10% waste), which equals 60 bags of 80 lb concrete or 79 bags of 60 lb concrete.
Does the 480 picket count include the pickets on the 2 gates?
Yes. As long as your 200-foot measurement includes the width of the two gate openings, the 480 pickets cover the entire 200 linear feet including both gates.
How long does it take to build a 200 ft wood fence with 2 gates?
For a two-person crew, Day 1 is spent augering the 28 holes and setting all posts in concrete; Day 2 is spent attaching the 83 horizontal 2×4 rails and hanging the 480 pickets; and Day 3 (half-day) is spent framing and hanging the two gates.