The short answer
358 mesh is a welded steel mesh panel with openings of about 76.2 mm by 12.7 mm (3 inches by half an inch) in 8 gauge, roughly 4 mm, wire. The openings are too small for fingers or the toe of a shoe and too tight for most cutting tools to get a grip, so it is one of the hardest fences to climb or cut. Schools use it on footpath and rear boundaries rather than the whole site.
On this page
If you have had a fencing contractor round to look at a school boundary, the number 358 has probably come up. It is a name, not a model number, and once you know what it means it is easy to judge where it is worth the extra cost.
Where the name comes from
358 describes the mesh in imperial units: an aperture of 3 inches by 0.5 inches, made from 8 gauge wire. In metric that is about 76.2 mm by 12.7 mm, with wire about 4 mm thick. The wires are welded at every crossing to make a rigid panel, which is then galvanised and usually powder coated, most often in dark green or black.
You will also see it sold as “prison mesh”, because it was first used widely around secure sites, and as “anti-climb mesh”.
Why it is hard to climb and cut
Ordinary school weldmesh has openings of 200 mm by 50 mm. That is too narrow for a foot to sit flat, but a determined climber can still get fingers and toes in. A 12.7 mm gap is too small for either.
Cutting is harder too. The wires are close together, so bolt cutters struggle to fit around one wire, and cutting a hole big enough to pass through means dozens of cuts rather than a few.
That makes 358 mesh good at the two things DfE’s guidance asks of perimeter fencing as a measure against intruders: deter, and delay.
How it compares with other school fences
| Panel | Aperture | Climb resistance | See-through | Typical fitted cost |
|---|---|---|---|---|
| Twin wire 656 or 868 | 200 mm × 50 mm | Moderate | Very good | £60 to £120 a metre |
| 358 mesh | 76.2 mm × 12.7 mm | High | Good face-on, closes up at an angle | £90 to £160 a metre |
| Steel palisade | Gaps between pales | Moderate to high | Poor | £75 to £140 a metre |
Prices are installed ranges from published UK contractor price guides, autumn 2026, at 2.0 m to 3.0 m and before VAT. They are a guide, not a quote.
Where schools use 358 mesh
Most schools do not need it all the way round. It earns its cost on the stretches where intrusion actually happens:
- rear and side boundaries backing onto footpaths, alleys or open land;
- stretches out of sight of the building and CCTV;
- around plant rooms, oil tanks or stores that attract theft or arson;
- anywhere the incident log shows people getting over.
A common pattern is 2.4 m twin wire on the visible boundaries and 3.0 m 358 mesh on the one or two weak runs. Both can be finished in the same colour, so the change is barely noticeable.
Things to check before you specify it
Visibility. Face-on, 358 mesh is easy to see through. At an angle it looks almost solid. That can be a benefit beside a footpath, where it limits people watching the playground, but it can block sight lines staff rely on for supervision.
Height. It is usually fitted at 2.4 m or 3.0 m. Anything over 2 m, or over 1 m beside a road, normally needs planning permission.
Fixings. The panel is only as strong as how it is held. Look for clamp bars and security fixings on the inside face, posts concreted to the depth the manufacturer sets, and a panel bottom close to the ground with no crawl gap.
Ratings. Some 358 systems are tested and certified to LPS 1175. You do not need a rated fence for most school boundaries, but if a contractor quotes one, ask for its listing in the LPCB Red Book. Our note on LPS 1175 security ratings explains the grades.
Cost on a typical stretch
A 120 metre footpath boundary in 3.0 m 358 mesh, with the old fence removed, typically lands between about £12,000 and £23,000 before VAT, using the ranges above. Add a gate if the stretch needs one. The cost calculator lets you mix 358 mesh with other fence types on one site.
For the wider picture of what a secure school boundary needs, see school security fencing, and for the standard panel most of the perimeter will use, weldmesh and twin wire fencing.
If your site walk has found a weak run and you want it priced, the form below takes two minutes.