Overhead netting is a suspended field of stainless steel mesh held above a space you want to keep using — a patio, a pet run, a kitchen garden, a courtyard, a chicken run or a play area — rather than a fence drawn around it. It raises a different question from fencing. A fence resists a sideways push; a field carries its own weight plus whatever lands on it, and snow, wind and rain change every number in the calculation. This guide sizes that field: the span between supports, the supports themselves, the edge cable that carries the load, the fall that sheds weather, the openings you work through, and the specification a factory can actually quote from.
Executive Summary
An overhead field is a tensioned membrane, not a lid. Five numbers govern it: the unsupported span, the spacing of the netting mid span support points, the catenary sag you will accept, the fall that drains the field, and the load path at the perimeter. Get those right and the mesh choice becomes a short, ordinary decision. Get them wrong and the same mesh that lasts thirty years on a vertical frame will fret against a staple line in one season. Overhead netting earns its place where a solid roof is impossible or too heavy — over a run, netting over a patio, or netting over a play area that must stay visible from the house. The reference specification is the animal fence mesh product page.
Planning a field over an area you use? Send the footprint, the support layout and the height above ground, and we will return a mesh and hardware take-off.
Quick Answer:
Quick Answer: Overhead netting spans between supports — usually 2.5–3.5 m between intermediate support points on a domestic field — and is held at its perimeter by a continuous edge cable rather than by clips or staples. Size the aperture from the smallest thing that must not pass, the rope from the heaviest load and the harshest exposure, and pitch the field at 1:12 or steeper so rain runs off. In snow country, either steepen the field or plan a support that can be lowered before the first snowfall.
Key Takeaways
- An overhead field is loaded in gravity, snow and wind uplift and carries almost nothing in bending, so fence rules of thumb do not transfer to it.
- Span drives everything: tension rises with the square of the span and falls as sag increases, which is why a netting mid span support is nearly always cheaper than a heavier rope.
- The perimeter is the load path. A continuous edge cable with a swage ferrule at every corner outperforms a perimeter of staples by a wide margin.
- Water and snow have to leave the field, so fall is a specification line rather than a construction detail.
- Overhead netting is a cover and a barrier, never fall protection and never a walking surface — put that in writing before anyone climbs on it.
Snow and wind figures for a covered area are not invented locally; they follow published design-load standards such as those maintained by ASCE, and a supplier who cannot quote against a named load case is guessing.
An Overhead Field Is Not a Fence
A fence is pushed; a field is pulled. Three loads act on overhead netting and almost none of them appear in fencing tables. The first is dead load — the mesh itself, roughly 1.5–3 kg per square metre for hand-woven rope mesh, plus the support cables and fittings that hold it up. The second is snow load: 100 mm of fresh snow weighs about 10 kg per square metre, and the same depth of wet, settled snow can reach 30–50 kg, an order of magnitude more than the mesh beneath it. The third is netting wind uplift, which presses a near-horizontal surface from below and reverses the direction the supports were designed for. Rain matters less for its weight than for where it settles, because a slack field forms a pocket, and a pocket becomes a pond and then an ice lens.
The Three Numbers That Set the Span
Overhead netting design starts with geometry, not with mesh. Measure the clear span you have to cover, decide how many netting mid span support points you will accept, and choose the sag you are willing to see. The physics is unforgiving in one direction and generous in the other. At a given load, tension rises with the square of the span: double the span at the same proportional sag and you quadruple the pull at the edge. Halve the sag and you double it again. That is why overhead netting span limits sit lower than most people expect, and why one extra support at mid span usually costs less than the heavier rope and heavier terminals needed to cross the same distance without it.
| Unsupported span | Sag under own weight | Field behaviour |
| Up to 2.5 m | 1–2% of span | stays flat, sheds rain |
| 2.5–3.5 m | 2–3% of span | workable, needs an edge cable |
| 3.5–5 m | 3–5% of span | pockets form, load concentrates |
| Over 5 m | More than 5% | add a netting mid span support |
Support Structure and Edge Fixing
The netting support structure has two jobs: hold the field up at intervals, and hand the tension to something that can take it. The perimeter matters more than the middle. Netting edge fixing is where overhead fields fail, and they fail the same way — a run of staples, clips or cable ties, each carrying a fraction of a load nobody added up. Replace it with one continuous edge cable running the perimeter in a single length where the geometry allows, woven into the mesh or threaded through it, terminated with a swage ferrule at every corner and every change of direction. Hand-woven rope mesh is a 7×7 construction: forty-nine wires per strand, so a single broken wire costs about 2% of that strand’s breaking load and the panel stays serviceable. That is not true of a fixing. A corner is the most heavily loaded point on the whole field and deserves a rated anchor rather than a tensioner taken up by hand.
A suspended field behaves like any tensioned line — its ends carry the entire load — and the same terminal logic applies. The wire rope fence factors guide sets out how end assemblies, braces and anchors are sized for that duty.
Snow, Rain and Wind on a Near-Horizontal Field
Netting snow shedding is a question of slope and stiffness, not of aperture. A field pitched at 1:12 — about 5° — drains rain reliably. Wet snow does not slide at 5°; it sits, compacts and gains weight. In a region with a real winter, specify 1:6 to 1:8, or accept that somebody will walk the field with a soft broom after a storm. Uplift pressure is the mirror image of the same problem: wind crossing a near-horizontal surface creates pressure underneath and suction above, and because pressure scales with the square of wind speed, a 40 m/s gust pushes four times as hard as a 20 m/s one. Netting wind uplift is driven by how much solid surface the wind meets, so a mesh field is the better choice in an exposed location — at around 90% open area the air passes through and only the wire has to resist drag. The wider argument about wind load, open area and enclosure specification belongs to the enclosure system guide; the point here is narrower: a field has no back face, so it has to be restrained on both, or it will flap and fatigue.
Light, Shade and Airflow Under the Mesh
Overhead netting is specified from two directions at once — what must not get in, and what must still get through. Aperture decides the first; the ratio of wire to pitch decides the second. Visual weight is rope diameter divided by aperture pitch, and open area is the complement of that ratio squared. A 2.0 mm rope at a 38 mm aperture covers roughly 5% of the field and leaves about 90% open; a 3.2 mm rope at 76 mm reads lighter at about 4% and 92% open while being the stronger of the two. Practical pairs: 20 mm aperture for small birds, 25–38 mm for a pet run or netting over a play area, 50–76 mm where the field should disappear overhead. Netting over a garden needs one extra thought, because 90% open area casts almost no shade — it will not substitute for a shade structure, and the plants underneath will simply grow into it. Budget a pruning pass into the design.
Access: Getting In, Getting Out, Taking It Down
A field with no opening is a cage you cannot service. Netting access opening design is easy when it is planned — one zipped or laced hatch at each working height, a ground-level door where a run meets its perimeter, and a netting access opening at the ridge where the field meets the top of a frame. Two rules do the work. Never cut an opening without reinforcing its perimeter, because a hatch edge needs the same continuous cable and swage ferrule a panel end does; that is where the load turns. And never splice mesh mid span: order panels or rolls sized so that every join lands on a support. Add release points at two corners so one person can slack the field for inspection.
Netting a Large Area: The Order Form
Large area netting is manufactured in the same units as a fence but bought differently, so the overhead netting specification has to be complete before a factory can answer it. Six lines are enough for a quotation you can compare. Footprint and clear height, with the support layout drawn. Aperture and rope diameter, with grade and finish — 304 for most sites, 316 where the air carries chloride. Format, panels or rolls, sized so joins fall on supports, with a take-off by area and a wastage allowance. The perimeter detail, including edge cable, corner anchors and every change of direction. The load case: your local snow figure and the wind speed the site must survive. And the inspection interval you intend to keep. Buy in rolls when netting a large area on long straight runs and tensioning on site; buy panels when the shape is irregular or the frame already stands. Order the mesh, fixings, terminals and edge cable as separate lines, because a mesh-only rate hides the 10–20% of hardware every job needs. Exposure decides which grade survives — the fencing material guide works through that chemistry — and the mesh rolls guide covers roll lengths, widths and cutting. Specify against the animal fence mesh range and every line above has a number attached to it.
When a Netting Field Is the Wrong Answer
Overhead netting is not a roof, and it is not fall protection. If the space has to stay dry, or be shaded by more than about 10%, or carry any load, then a solid or glazed structure is the right answer and a mesh field is a compromise. If people will walk on it, store on it or clean it in place, it is the wrong material entirely — fall arrest is a separate discipline with its own certification. And if the real requirement is exclusion at ground level, a field overhead does nothing about it; that is a perimeter job, and the small animal fence guide shows how a perimeter, its groundline and its closures are specified together. Where a mesh field does win is where a light, open, corrosion-proof cover has to span an area you use, keep its daylight and airflow, and hold its shape for decades.
FAQ
It covers a space you use rather than enclosing it — a patio, pet run, chicken run, courtyard, kitchen garden or play area that needs protection from above without losing light. The mesh is suspended between supports and anchored at its perimeter, so it behaves as a cover and a barrier at the same time.
Plan on 2.5–3.5 m between intermediate support points for a domestic field, with a netting mid span support beyond that. There is no rigid maximum, but tension rises with the square of the span, so longer runs are usually cheaper to solve with one more support than with a heavier rope and heavier terminals.
A slack field will, and that is the failure to design out. Pitching the field at 1:12 sheds rain but not wet snow, so snow country needs 1:6 to 1:8, or a support that can be lowered before winter. Snow at 30–50 kg per square metre across a span will find the weakest fixing first.
No. A 2.0 mm rope at a 38 mm aperture covers about 5% of the field, and a 3.2 mm rope at 76 mm about 4%, so roughly 90% of the daylight still reaches what is underneath. It will not shade a planting bed or a seating area the way a solid canopy would.
Tell us the span, the support layout and the site’s exposure, and we will size the field, the edge cable and the hardware together — start with the footprint.