Planning a field shelter: area per horse, structure, timber protection and permission

DB David Bohler · 2026-09-20

A field shelter is quickly bought and just as quickly too small, too low or facing the wrong way. This guide works out the area per horse, shows the structure from post to batten and explains what protection by design and the planning rules ask for – with sources.

When a field shelter is required

Not every horse needs a building. The Defra code of practice for the welfare of horses, ponies and donkeys puts it plainly: some horses, particularly native breeds, are capable of living outdoors throughout the year, provided they can obtain shelter from the prevailing winds, summer sun and flies – and that shelter can be natural, such as trees or hedges, or man-made, such as a field shelter. Donkeys are the exception named in the code: they need roofed shelter with solid walls and a clean, dry standing area.

The code is not an offence in itself, but a court will look at whether you complied with it when deciding a welfare case. What it does not give is a floor area per horse – so the sizing below comes from the German guideline, which does.

How big does a field shelter have to be?

The German welfare guideline for horse keeping (2009) is the most concrete source on shelter size, and it is widely misquoted. The formula (2 × WH)² – WH being the height at the withers – belongs to the loose box and to the lying area in a closed yard. For weather protection the guideline gives the smaller figure: at least 3 × WH² of lying area per horse, reduced to 2.5 × WH² where layout and management are favourable, excluding the feeding area. Its own table confirms it: 1.68 m at the withers gives 8.47 m².

Height at withers (WH)	Pony 1.40 m	Horse 1.70 m
Area per animal (3 × WH²)	5.88 m²	8.67 m²
Reduced (2.5 × WH²)	4.90 m²	7.23 m²
Two animals	11.76 m²	17.34 m²
Clear height (1.5 × WH)	2.10 m	2.55 m

In practice a standard 3 × 6 m shelter – 18 m² under roof – takes two horses or three ponies. For larger groups the guideline prefers several small shelters over one big one, and it requires the shelter to take all animals at the same time and to stay accessible to low-ranking ones. A single narrow doorway fails that test the moment the boss horse parks in it.

Height, openings and doorways

For stable buildings the same guideline asks for a clear ceiling height of at least 1.5 × WH, recommending 2 × WH for new buildings. For a field shelter the figure is not stated explicitly – it is a sensible transfer, and the reason to measure the clear height at the open front: 1.5 × 1.70 m is 2.55 m. A horse throws its head up as it walks in.

Doorways in group housing are either narrow enough for one horse only (0.80 to 0.90 m) or wide enough for two to pass each other comfortably (at least 1.80 m). Anything in between invites crowding. And gaps with a clear width of roughly 6 to 30 cm are listed as a known hazard – a hoof gets caught there. Close them properly or leave them much wider.

Site and ground

The closed back goes towards the prevailing weather, the open front away from it. The ground decides the rest: horses stand where it is dry and churn up everything else. All animals, whatever their rank, must be able to stand at the same time on ground that is not a quagmire, and the main routes to water, feed and shelter must stay passable. A built-up surface usually consists of a load-bearing layer – with drainage where needed – a separating layer and a walking layer. Keep access for straw, muck and materials in mind as well; it has to work in November.

Structure: posts, purlins, rafters, roof

The usual build is a mono-pitch roof: four to eight posts, two purlins on top, rafters across them and battens over those. The fall runs towards the back, away from the entrance – otherwise every litre off the roof lands exactly where the horses stand. At the front the roof projects; a roof overhang of 1.20 m is common on kits and keeps driving rain out of the open side.

Typical kit sections as a guide: rafters 8 × 16 cm, battens 4 × 6 cm, posts 10 × 10 to 12 × 12 cm, cladding 24 mm. Battens are laid in the plane of the roof, not horizontally, or they touch the rafter on one edge only. Cover is normally galvanised corrugated steel, ideally with an anti-condensation lining: under a cold metal roof moisture forms and drips onto the animals.

Knee braces at the front posts are part of the structure, not decoration. The open side has no wall panel to stiffen it; without a diagonal the frame racks under wind or when a horse leans on it.

Field shelter in section: mono-pitch roof falling to the back, overhang above the open front, posts kept clear of the ground.

Base and foundation: timber does not belong on the ground

The most common mistake is the buried post. It lasts a few years – one supplier states about 15 years for its buried masts – and then rots exactly where everything hangs together. Protection by design asks for clearance instead: at least 30 cm above hard paving, reduced to 15 cm where a gravel strip or a fall of at least 2 % keeps splash water away. The post therefore sits on a metal post base in a pad foundation or on a concrete plinth, never in the soil.

Post base in section: H-shaped post support in a pad foundation, clearance from the underside of the post to ground level – the post is never cast into concrete.

That keeps the timber in use class 0, which needs no chemical treatment – provided the rest fits too: kiln-dried, planed solid timber, connections that cannot trap water, end grain protected, rainwater led away, and vertical members no larger than 16 × 16 cm so that checking stays small.

Snow and wind

Two actions govern the structure and they pull in opposite directions. Snow presses down and sizes rafters, purlins and posts. Wind lifts an open, free-standing roof and sizes the anchorage – a shelter held down by its own weight alone is a kite in a gale.

In the Eurocodes the snow load on the roof follows s = μ_i · C_e · C_t · s_k: s_k is the ground value and depends on the snow zone and the altitude of the site, μ_i on the roof shape – 0.8 for a mono-pitch roof up to 30° – C_e on the exposure and C_t on heat loss, which is 1.0 for an unheated shelter. The zone follows the administrative area of the site. The numbers themselves sit in the national annexes; a structural engineer or carpenter has them.

Front: open, partly closed or two entrances

The German guideline asks for either at least two entrances or an open front in group housing, so the classic three-sided shelter already satisfies it. Partial fronts still make sense: they cut driving rain and draught, and two separate 1.50 m entrances give a low-ranking horse a second way out.

Planning permission in England

Keeping horses for leisure is not agriculture in planning terms, and that is where most field shelters come unstuck. The Town and Country Planning Act defines agriculture as including the breeding and keeping of livestock and the use of land as grazing land; the agricultural permitted development rights in the GPDO apply to agricultural land in an agricultural unit of 5 hectares or more, used for the purposes of a trade or business, and only for buildings reasonably necessary for agriculture on that unit. A private paddock rarely meets that. The householder rules for outbuildings do not help either: they cover buildings incidental to the enjoyment of a dwellinghouse, not a field. Ask the local planning authority before you buy timber – and note that a shelter on skids may be treated differently from a fixed one.

Cost: kit or self-build

For orientation, German supplier list prices retrieved on 20 September 2026, self-build kits including VAT, without foundation, delivery or assembly: a 3 × 6 m larch shelter with a 1.20 m canopy from about €2,750; the same range at 3.2 × 6.3 m for €2,965, at 3.2 × 7.3 m for €3,555 and at 3.2 × 8.3 m for €4,150; the version with partial fronts at 3.2 × 6.3 m for €4,000. Those are individual list prices, not market statistics.

Planning it in HolzBau 3D

The planner has the field shelter as a template: width, depth, clear height at the front, roof pitch, overhang and the front layout – open, entrances at the sides or one central entrance – are entered, the rest follows. You get a parts list, cut lengths, estimated quantities of post anchors, angle brackets and screws, and a workshop drawing for every machined timber.

Sources and standards

Standards are not free to read and are named here for verification only. What applies is always the edition in force at the building location.