Takeoff & Estimating — Concrete, Sitework & Utilities

Barbed Wire

Twisted steel fence wire with barbs, taken off by LF, strands and posts.

Quick Answer

Barbed wire is steel fence wire with sharp points, or barbs, twisted at regular intervals along its length. It is strung between posts for livestock, security and boundary fencing, or along the top of chain link. In takeoff, fence run is measured in linear feet, with wire strands, posts, braces and gates counted separately.

The Full Picture

Barbed wire is made of strands of steel wire twisted together with short barbs wrapped at intervals. The design most associated with commercial success was patented by Joseph Glidden of DeKalb, Illinois, on November 24, 1874. Today it is used for agricultural and ranch fencing, perimeter security on industrial and utility sites, and as outriggers above chain link fence. Steel is usually galvanized, and ASTM A121 is the standard that covers metallic-coated carbon steel barbed wire.

Where it appears in the documents: civil site plans and fence layouts show the fence alignment and gates, a fence schedule or detail gives post size, post spacing, number of strands and gate type, and the specification in Division 32 (Exterior Improvements) covers materials and installation. Check the section number in the project manual and don't assume it. Barbed wire at the top of a chain link fence is often a separate note on the detail, which makes it easy to miss.

How it is quantified: the fence is measured in linear feet along the centerline, less gate openings. Wire is carried in linear feet of strand, which is fence length multiplied by the number of strands, plus an allowance for laps, splices and wrapping at posts that varies by installer. Line posts are counted each based on spacing, and corner, end, gate and brace posts are counted separately because they are larger and set deeper or in concrete. Gates, hardware, tension wire, bracing and any clearing of the fence line are separate lines.

Pricing pitfalls include counting posts from the total length without separating braced posts, missing that the top rail or outriggers carry extra strands, ignoring grading or clearing along the line, and failing to see that post holes in rock or frozen ground change installation cost. Some jurisdictions restrict barbed wire near sidewalks or in residential zones, so check the local code and the site plan notes before pricing.

Real Examples

→Worked takeoff: three-strand fence: A 1,200 LF fence line has one 16 ft gate opening, so fence run = 1,200 - 16 = 1,184 LF. With 3 strands, wire = 1,184 x 3 = 3,552 LF. If the estimator adds a 5% allowance for laps and waste (an assumption, adjusted to the installer), wire = 3,552 x 1.05 = 3,730 LF. With line posts every 10 ft, 1,184 / 10 = 118.4, so 119 spaces and 120 posts in total. If 6 of those are corner, end and gate posts counted separately, line posts = 114 EA and braced posts = 6 EA. The gate is 1 EA.

→Barbed wire on chain link: A utility yard shows 600 LF of 6 ft chain link with three strands of barbed wire on top. The estimator takes the chain link as 600 LF, then adds 600 x 3 = 1,800 LF of strand, plus the extension arms (outriggers) counted by the post and by the line post spacing in the detail.

→Fence line clearing: A ranch fence crosses 300 LF of brush. The estimator carries the fence in LF, and adds a separate clearing line for the brush, because the fence price assumes a clear path.

Common Misconceptions

People assume: Barbed wire fence is one price per linear foot.

Actually: Strands, line posts, braced posts, gates and hardware are priced separately. A unit price per LF is only valid when the post spacing, strands and gate count match the assumptions behind it.

People assume: The strand count doesn't change the footage.

Actually: Each additional strand multiplies the wire footage along the same run, so a 4-strand fence uses a third more wire than a 3-strand fence.

Does MeltPlan Solve This?

Partially — adjacent

Fence runs, gates and post counts are physical items an estimator measures from site plans. MeltPlan's takeoff uses AI to pull quantities from PDF plans, and US-based experienced estimators review and adjust them into a verified takeoff. Wire strand counts and spacing follow whatever the fence detail specifies.

Count fence LF and gates from site plans →

Frequently Asked Questions

How do you take off barbed wire fence?

Measure the fence centerline in linear feet less gate openings, multiply by the strand count for wire footage, and count line posts, corner and brace posts, and gates separately. Add an installer-appropriate allowance for laps and waste.

How many posts do I need?

Divide the fence run by the post spacing in the detail, round up and add one for the end. Then count corner, end, gate and brace posts separately because they are larger and are set differently. Spacing varies by fence type and local practice.

What standard covers barbed wire?

ASTM A121 covers metallic-coated carbon steel barbed wire, with aluminum, zinc or zinc-alloy coatings. The project specification will name the grade and coating class required, so use the spec rather than assuming one.

Which spec division covers fencing?

Fences and gates are typically in Division 32 (Exterior Improvements). Verify the section against the project manual, since numbering and scope differ from job to job.