Release Pen Netting UK Guide: Mesh, Gauge & Lifespan

Wrong netting specification is one of the most avoidable costs in game rearing, and one of the most common. It usually surfaces three days after the poults go in. There may be a gap at ground level where something has pushed through, or a section of top netting sagging under a branch that should have been cleared before the first roll went up. The specification looked fine on paper. Yet, in the pen, it was wrong for the job. The trouble is that by then the options are limited to repairs rather than proper fixes.

This guide covers release pen netting UK specification from the ground up. For example, what top netting and side netting are each being asked to do, when knotted construction earns its keep over knotless, how UV stabilisation affects lifespan in woodland pen conditions, and how to size an order accurately, including gate kits and accessories most keepers leave to a second run. If the wire versus plastic decision is still live, settle that first. Otherwise, the specification detail follows below.

Get it right first time, and you will not think about it again until the five-year inspection.

What Your Top Netting & Side Netting Need to Do

Top netting and side netting face different threats and carry different stresses. Treating them as the same job is where a lot of orders go wrong.

Your top netting is primarily there to keep corvids and raptors out and stop birds flushing too early. For most release pen applications, 50mm or 75mm mesh in knotted polyethylene gives the right balance between coverage, weight, and light penetration. The latter matters more than most keepers allow for on woodland pen sites. Heavier gauge means more durability under tension and snowload, but also more shading. For large-span woodland pen roofs, that trade-off is worth thinking through before ordering.

Side netting carries harder work at ground level. The British Association for Shooting and Conservation (BASC) release pen guidance specifies a fence height of 2 to 2.1 metres, with 30cm turned out at the base and pegged down to prevent digging, and a further 30cm fringe at the top to deter climbing. An electric fence around the outside perimeter (two strands at 15-30cm and 40-50cm) is also recommended where fox pressure is significant. For woodland pens, BASC advises clearing overhanging branches inside and outside to four metres: netting compressed by timber will fail faster and tension poorly [1].

Mesh Size for Side Netting

Mesh size at ground level is where most side netting errors begin. The specification changes significantly as you move up the fence:

• For the lower 60cm, use 25mm mesh in wire or close-mesh knotless plastic to exclude weasels and stoats.
• Above 60cm, 50mm knotless or jumbo netting gives adequate predator resistance with faster erection.
• For anti-fox top netting across the roof, 50mm to 75mm is standard.

Knotted vs Knotless: Which Construction Holds up In a Working Pen

Knotted netting holds a genuine strength advantage at the knot point under sustained tension. It remains the preferred choice for top netting on larger pens where spans are long, and wind loading is significant. The knot locks mesh geometry in place even when individual strands are stressed.

Knotless netting, extruded rather than woven, has no knot point to fail, but relies on strand integrity. It is lighter, easier to handle, and faster to hang. The Game and Wildlife Conservation Trust’s (GWCT) GWCT Senior Adviser Mike Swan is direct on this. Modern extruded black plastic is entirely fit for purpose on the upper sections of the pen. The proviso is ground level. Rats will chew through plastic netting, so wire netting for the bottom 60cm is the correct call. Jumbo netting above that is the combination that has stood up in practice across decades of pen building [2].

Swan also flags track clearance. Always clear a 4m-wide track and site the fence in the middle. Netting tight against vegetation will not hold its specification regardless of construction type.

Gauge: Where Heavier Netting Earns Its Cost

Gauge is where buyers often cut corners and regret it. A lighter gauge net may feel adequate going up, but degradation accelerates under UV exposure and physical stress, including brambles, branch rubbing, and bird pressure. For a pen intended to last more than two seasons, heavier gauge side netting pays back quickly in reduced repair time.

UV Stability & Pen Netting Lifespan

UV stabilisation is not a binary quality. It is a spectrum, and the difference between a well-stabilised netting and a cheaper alternative becomes apparent in year two or three, not at installation. Woodland pen applications are more exposed than open country suggests. A canopy filters UV partially, but netting on southern faces or any exposed position degrades faster without adequate stabilisation built into the polymer.

Virgin-grade polyethylene with UV inhibitors incorporated at manufacture, not applied as a surface coating, gives the most consistent long-term performance. For volume orders specified against a five-plus year replacement cycle, that distinction is worth raising before you commit.

GWCT research is detailed that overcrowding and poor habitat management shorten pen life faster than netting specification. At up to 1,000 birds per hectare, woodland flora is unlikely to suffer lasting damage. Beyond that, problems compound and habitat loss can extend 15 metres outside the pen perimeter. A correctly stocked, actively managed pen should remain serviceable for many years. Netting becomes the limiting factor only when the specification was wrong at the outset, or maintenance has been deferred [3].

Build these three checks into your seasonal routine:

• Inspect side netting annually at ground level for signs of chewing, rust, or sagging.
• Check top netting after significant snowfall or storm for tears and compression damage.
• Build netting replacement into your five-year budget before the specification forces the issue.

Sizing Your Release Pen Netting Order

Most keepers know the perimeter of their pen. Fewer have a reliable figure for total top coverage, and almost none have factored in gate kits and accessories before the first roll goes up.

Work from the perimeter first. Measure the total run of side netting, add 10% for terrain and overlaps, and specify height based on fence post height minus the buried and turned-out sections. For top netting, calculate the enclosed area in 50-metre roll widths. Allow for overlap at each join, as rolls lap and tie rather than butt.

On stocking density, GWCT sets two limits that directly affect pen size. The standard ceiling is 1,000 pheasants per hectare (400 per acre). This is the threshold at which overcrowding begins to affect woodland flora. In ancient semi-natural woodland, that reduces to 700 birds per hectare (280 per acre). GWCT also specifies that release pens should not exceed approximately one-third of total shoot woodland. This is a constraint that may bind before the density limit does. Work backwards from your bird numbers and woodland area to confirm your pen footprint is within both limits before specifying quantities.

For gate kits, re-entry funnels, and fencing accessories, do not leave these to a second order. Gate kits and fencing accessories are available alongside the netting range. For irregular pens or multiple sections, call our team. A conversation will get you to the right quantities faster than estimating from a plan.

Get Your Pen Netting Right Before the Season Starts

Specification errors do not announce themselves until the pen is under pressure. By which point the options are repairs, not fixes. The difference between a pen that performs for five seasons and one that needs work in year two almost always traces to decisions made before the first roll went up.

Here is what this guide has covered:

• Use 25mm mesh at the base, larger above, with top netting specified separately for span, weight, and light penetration.
• Knotted construction holds under tension, but knotless is faster to hang, and wire at ground level is never optional.
• UV stabilisation incorporated at manufacture outperforms surface treatments over a five-plus year cycle.
• Stocking density determines pen longevity as much as netting specification, and GWCT’s 1,000 birds per hectare ceiling applies before your netting choice does.
• Include gate kits and accessories from the outset because a second delivery run costs more than the planning would have.

Collins Nets has been supplying release pen netting to shoots across England, Scotland, and Wales for more than 35 years. That depth of experience sits behind every product in the range, from anti-fox top netting and jumbo side netting through to gate kits and fencing accessories, and it is what our team brings to any conversation about pen specification. Whether you are building a new pen from scratch or replacing sections before the 2026 season, the right quantities and the right specification are a phone call away.

Call 01308 485422 or use the contact form to discuss your pen specification with our team. Lines are open 7.30am to 4.00pm, Monday to Friday.

External Sources

[1] British Association for Shooting and Conservation (BASC), Pheasant Release Pen (2025): https://basc.org.uk/gamekeeping/stock-and-poultry-advice/pheasant-release-pen/

[2] Game and Wildlife Conservation Trust (GWCT), Mike Swan, Making the Perfect Pheasant Release Pen (2022): https://www.gwct.org.uk/blogs/news/2022/april/making-the-perfect-pheasant-release-pen/

[3] Game and Wildlife Conservation Trust (GWCT), Release Pens: https://www.gwct.org.uk/advisory/guides/woodland-conservation-and-pheasants/release-pens/