Wool insulates the point of contact, so a sheep brushing a single hot wire may barely feel it — and a fence that only startles is one the flock eventually walks through. The working setup uses more strands, higher voltage, and a ground-return design than most first installs.
Permanent vs. Temporary: Spacing
A permanent sheep fence uses up to five strands; a temporary one up to three, with the lowest strands at 10-inch intervals so nothing slips between them.
AHDB’s guidance for permanent sheep fencing spaces the bottom three strands at roughly 6-inch gaps and the top two at about 10-inch gaps — near 6, 12, 18, 26, and 36 inches from the ground. Oklahoma State goes heavier for sheep-and-cattle operations: a seven- or eight-wire fence about 48 inches tall, with one common design starting the bottom charged wire 6 inches above grade and alternating charged and ground wires at 5, 6, 8, and 10 inches.
Temporary fencing is simpler: up to three strands at roughly 10-inch intervals — 10, 20, and 30 inches off the ground.
- Permanent: up to 5 strands, tighter at the bottom, rigid posts at corners and direction changes.
- Temporary: up to 3 strands, wider spacing, light step-in posts.
- Line posts: 23–33 feet apart on longer runs.
Don’t drop the lowest wire to the ground to stop lambs crawling under. Grass contact shorts the circuit, and a shorted fence delivers almost nothing. Keep the bottom strand as high as your smallest animal’s nose allows.
How Many Volts Do Sheep Need?
Sheep need a minimum of 5,000 volts on the wire; heavy-coated livestock generally need to sit above that 5 kV mark, higher than a dry-coated cow requires. The reason is the wool.
Measure voltage at the far end of the run, not the energizer. A fence reading 7,000 volts at the terminal and 3,000 at the far corner has a grounding or connection problem, not a fence that’s “working fine.” Test at the worst point — usually the farthest corner — and treat anything under 5 kV there as unfinished.
| Fence Type | Strands & Spacing | Voltage Target |
|---|---|---|
| Permanent sheep | Up to 5; bottom three ~6 in apart, top two ~10 in | 5,000+ volts on the wire |
| Permanent sheep + cattle | 7–8 wires, ~48 in tall | 5,000+ volts on the wire |
| Temporary / movable | Up to 3; ~10 in intervals | 5,000+ volts on the wire |
| Offset predator wire | 1 strand, ~12 in out and ~6 in up | Tied to main fence circuit |
Grounding
A sheep fence needs three or four 6-foot ground rods driven in parallel about 6 feet apart (Oklahoma State’s count).
Grounding matters more for sheep than most livestock. Wool blocks the shock path, so many sheep fences run alternating hot and ground wires, with the animal completing the circuit by touching both — better on wool than relying on hoof contact. Skip the rods and you build a fence that reads full voltage and still won’t turn a sheep.
Run power on cable rated for electric fencing — not household or industrial cable rated only to 600 volts. On permanent runs, bury it about 12 inches deep inside rigid plastic pipe, ends pointed downward so water can’t collect.
Site the energizer centrally to shorten runs and cut voltage drop, and mount it under cover. Match the joule rating to total fence length and animal load — sized energizers for sheep fencing compare joule output against wire length so you don’t under-power a long perimeter.
Gates, Corners, and the First 24 Hours
Gates need insulated hardware so the circuit stays live when shut. AHDB specifies an insulated gate hook with tape or a spring, plus insulators on the handle and opposite side.
Corners and every change of direction need a stronger post than a straight-run line post — that’s where tension pulls sideways, and a leaning corner takes the whole wire height with it.
Then watch it. Oklahoma State recommends observing the fence for the first hour and checking regularly through the first 24 hours: walk the line with a tester, look for grass touching the bottom strand, and find spots animals have tested. You’ll know it’s right when a sheep touches a wire once, pulls back, and doesn’t try again.
Details live in the Oklahoma State electric fencing for sheep fact sheet and AHDB’s fencing setup guidance.
FAQs
Why does my fence tester show good voltage but the flock still walks through?
That usually points to grounding, not voltage. Wool insulates the contact point, so a sheep touching only a hot wire may not complete the circuit. Check the ground rods first, then test at the far end — under 5,000 volts won’t stop a determined sheep.
Can I run a sheep fence off a single strand of tape?
No, not reliably. A single strand leaves gaps sheep push through, especially lambs. Up to three strands works for temporary paddocks and five for permanent runs, spaced tighter at the bottom.
How close to the ground should the lowest wire sit?
High enough that grass won’t touch it — roughly 6 inches is the common minimum.
References & Sources
- Oklahoma State University Extension. “Electric Fencing for Sheep.” Source for permanent fence height and wire count, ground rod count, and the first-24-hours monitoring advice.
- AHDB. “How to Set Up Electric Fencing for Cattle and Sheep.” Source for permanent and temporary strand spacing, gate hardware, and buried cable depth.