Garden Solar Panels: Ground-Mounted Rules, Costs and Yields

Garden solar panels on a ground-mounted frame need no planning permission in England, Scotland and Wales if the panels cover no more than 9 square metres, about four standard panels or 1.8 kW, and height and boundary limits are met. Northern Ireland allows 14 square metres. Larger arrays need planning permission, and one comparison site puts ground mounting at roughly 15 to 35 percent more than a roof system.

The extra cost goes on the frame, the foundations and the cable run back to the house. In return you choose the direction and angle, which matters most when your roof faces east, west or north, is shaded, or cannot be used. This guide covers the planning limits in each nation, frame and foundation types, trenching and cable sizing under BS 7671, costs as observed in November 2026, yields compared with a roof, and plug-in solar on a garden stand.

When a ground-mounted array makes sense

A good south-facing roof is almost always the cheaper place for panels: the structure is already there, the cable run is short and the panels are out of the way. A garden array earns its extra cost in a few situations:

• The roof faces the wrong way. A north-facing slope gives about 53 percent of the south-facing yield in London by PVGIS figures; an east or west roof about 77 to 80 percent.
• The roof is shaded by a taller neighbour, trees or a chimney stack that an open part of the garden escapes.
• The roof cannot be used: a listed building, a roof due for replacement, an awkward hipped or dormered roof with little clear area, or a thatched or fragile covering.
• You have land to spare, such as a long rear garden, paddock or smallholding, where a larger array with planning permission is realistic.

It makes little sense in a small, enclosed garden where fences and trees shade the ground for much of the winter, or where the array would take space you would rather use.

Planning rules for ground-mounted solar in each nation

Planning is devolved, and stand-alone solar has its own permitted development class in each nation. “Stand-alone” means equipment not installed on a building. The limits below apply to houses; blocks of flats and non-domestic land have separate rules.

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England

Class B of Part 14 of the General Permitted Development Order covers stand-alone solar within the curtilage of a house or block of flats. The order that came into force on 27 August 2026 rewrote the limits for houses. For a house, development is not permitted if:

• any part would exceed the lowest applicable height limit: 1 metre within 5 metres of the boundary and forward of the principal elevation; 2 metres within 5 metres of the boundary; 2 metres in a conservation area where the array is nearer a bounding highway than the house; 4 metres in any other case;
• in a World Heritage Site, it would be nearer a bounding highway than the house, or within 5 metres of the boundary;
• it would be within the curtilage of a listed building or on a scheduled monument;
• the panels’ surface area would exceed 9 square metres;
• in the case of plug-in solar, any part would be installed on a wooden fence, gate, wall or other enclosure.

Two conditions apply. The array must be sited, so far as practicable, to minimise its effect on the amenity of the area, and removed as soon as reasonably practicable when no longer needed. And where it would sit in a conservation area nearer a highway than the house, or on “article 2(3)” protected land within 5 metres of the boundary, you must first apply to the council to decide whether its prior approval is needed for the appearance.

For houses the order no longer limits the number of stand-alone arrays or their longest dimension; for blocks of flats both limits remain. Whether a council would treat several 9 square metre frames side by side as separate installations has not, as far as we know, been tested. If you plan more than one frame, apply for a lawful development certificate first.

Scotland

Scottish stand-alone solar at a dwelling falls under Class 6B, inserted in 2009. It allows one free-standing array per dwelling with no more than 9 square metres of panels and no part higher than 4 metres. The distance from the curtilage boundary to the array must be at least the array’s height, so a 2 metre high frame must stand at least 2 metres from the boundary. In a conservation area or World Heritage Site the array must not be visible from a road, and it is excluded within the curtilage of a listed building. We found no change to Class 6B in the 2024 amendment order, which widened the rules for panels on buildings; check with your council, which can issue a certificate of lawfulness.

Wales

Wales has its own Class B in Part 40. It allows one stand-alone array per house, no higher than 4 metres. Within 5 metres of the curtilage boundary it may not exceed 2 metres or be within 5 metres of a highway. In a conservation area or World Heritage Site it may not sit between a bounding highway and the house, and it is excluded within the curtilage of a listed building. The panel area is limited to 9 square metres, and no dimension of the array, including any housing, may exceed 3 metres.

That last limit matters more than it looks. A standard 54-cell roof panel measures about 1.72 to 1.76 by 1.13 metres. Four of them in any rectangular layout exceed 3 metres in one direction. On our reading, a Welsh permitted development array of standard panels is therefore limited to two, about 0.9 kW, unless smaller panels are used. Ask the council if you want certainty.

Northern Ireland

Northern Ireland’s Class C allows one stand-alone array within the curtilage of a house, up to 14 square metres, no part higher than 2 metres, and no part nearer a bounding road than the nearest part of the house. Within the curtilage of a listed building, listed building consent must have been granted first. Its primary purpose must be to provide heat or energy for use within the curtilage. The order limits the area of the stand-alone solar installation rather than the panel surface, so a frame that projects beyond the panels may count against it. Fourteen square metres takes up to six or seven standard panels, roughly 2.7 to 3 kW, depending on how the frame is measured.

Listed buildings, Article 4 and neighbours

A ground array within the curtilage of a listed building falls outside permitted development in every nation and may also need listed building consent. Councils can withdraw permitted development rights with an Article 4 direction, common on planned estates and in conservation areas. Permitted development does not override covenants in your deeds or a lease, and it does not stop a neighbour complaining about glare; siting the array to face away from windows avoids most disputes.

What fits in 9 square metres

The 9 square metre limit is measured on the surface area of the panels, not the frame or the ground it covers.

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A permitted development garden array in Great Britain is therefore a small system, about 1.8 kW, half the size of a typical roof installation. That shapes the economics: the trench, the frame, the inverter and the certification cost much the same for four panels as for eight, so the cost per kW is higher than on a roof. A larger array is possible with planning permission, which a council can grant where the array is not prominent.

Yields: what a better tilt gains over a roof

A garden frame lets you choose direction and angle. PVGIS figures for London, in kWh per kW of panels a year:

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The gain is real only against a poor roof. Against a good south-facing roof there is none. PVGIS puts the optimum angle at 39 to 43 degrees facing south across the UK, and anything from 30 to 50 degrees is within about 1 to 2 percent of it.

For a four-panel, 1.8 kW array at 40 degrees, that means roughly 1,840 kWh a year in London (1.8 × 1,022), about 1,600 in Manchester (1.8 × 888) and about 1,540 in Glasgow (1.8 × 855). Our guide to how much electricity a solar panel produces gives monthly figures for nine cities.

Ground-mounted frames are open underneath, so panels run cool, which PVGIS already assumes for any rack-mounted array. Bifacial panels, which also collect light reflected onto their rear side, are sometimes promoted for ground arrays; the gain depends on the ground surface and the frame height, and we have not found UK domestic data to quantify it.

Shade: the garden’s biggest problem

At ground level, fences, hedges, sheds and trees shade panels far more than they shade a roof. The MCS shade method treats any object within 10 metres of the array as near shade, which counts much more heavily than distant objects: in MCS’s own example, an obstacle that cuts the predicted yield by 11 percent from a distance cuts it by 40 percent when closer than 10 metres.

Winter sun is very low. At noon on the shortest day, the sun stands about 15 degrees above the horizon in London, 13 degrees in Manchester and under 11 degrees in Glasgow, from the latitude and the sun’s 23.4 degree winter tilt. A 1.8 metre fence therefore casts a noon shadow about 6.7 metres long in London and 9.5 metres in Glasgow in late December. At the March and September equinoxes the same fence’s noon shadow is about 2.3 to 2.7 metres.

The practical rule: place the array as far as you can from obstacles to its south, east and west, and accept that it will lose some low winter sun in a typical suburban garden. Winter contributes little to annual yield anyway; December gives under 4 percent of the year in London. Shade from March to October matters much more.

Row spacing for two rows

If you mount two rows, the front row shades the back one when the sun is low. A landscape panel 1.13 metres deep tilted at 35 degrees rises about 0.65 metres and occupies about 0.93 metres of ground. To keep the back row clear at noon on the shortest day in London, the rows need about 2.4 metres of clear ground between them, a row pitch of about 3.3 metres. To keep it clear at the equinoxes only, about 0.8 metres is enough, a pitch of about 1.75 metres. Most designers choose a compromise between the two.

Frames and foundations

A ground frame has to hold the panels at the right angle for decades and resist wind lifting them. The government’s plug-in solar specification, for example, requires mounting systems to be designed for UK wind loads under BS EN 1991-1-4 and its UK National Annex, and snow loads under BS EN 1991-1-3; the same standards are the usual basis for any ground frame design.

Frame types.

• Fixed A-frame or rail frame. Aluminium or galvanised steel legs carrying horizontal rails, with panels clamped on top. The most common domestic design; height and tilt are set at installation.
• Single-pole mount. A steel post carrying a panel table. Higher off the ground, so less shade from fences and easier mowing underneath, but taller and more visible, which can conflict with the 1 and 2 metre boundary limits.
• Ballasted frame. Trays or frames weighed down with concrete blocks or slabs, with no digging. Useful on a patio, over services, or where you may want to move the array; the ballast must be calculated for wind uplift.
• Low tilt frames. Some garden kits sit close to the ground at a shallow tilt. They keep below the 1 metre limit forward of the house but lose some output and catch more shade.

Foundations.

• Ground screws. Large galvanised steel screws driven into the ground by machine. Quick, little spoil, and removable; their holding capacity depends on the soil, which may need testing on site. Stony ground and buried services can prevent their use.
• Concrete pads or piles. Holes filled with concrete around a post or with cast-in bolts. Reliable in most soils, but slower, permanent and harder to remove when the array is retired.
• Ballast. As above, no ground penetration at all, at the cost of a heavier structure.

Whichever you choose, the frame should come with the installer’s or manufacturer’s structural confirmation for your site’s wind exposure. A light frame on an open, elevated site needs more anchoring than the same frame in a sheltered suburban garden.

Height affects planning as well as shade. A portrait 1.76 metre panel at 35 degrees reaches about 1 metre above its lowest edge; on legs with 30 centimetres of ground clearance the top sits at about 1.3 metres, within the 2 metre limit near an English or Welsh boundary but above the 1 metre limit in front of an English house. Mounting the panels in landscape keeps the top edge at about 0.95 metres on the same legs.

Trenching and armoured cable under BS 7671

The cable from the array to the house is where garden installations differ most from roof systems, and where the IET Wiring Regulations, BS 7671, apply directly.

Regulation 522.8.10 of BS 7671, as summarised by the IET’s Wiring Matters in July 2024, requires buried cables to meet three conditions. The article was written under the 2022 amendment; the current edition is BS 7671:2018+A4:2026, which your electrician works to. Buried cables must:

• be at a sufficient depth to avoid damage from any reasonably foreseeable disturbance of the ground, an engineering judgement rather than a fixed figure;
• have their location marked by cable covers or a suitable marker tape;
• either have an earthed metallic armour or sheath, or be unarmoured cable in a conduit or duct giving equivalent protection against mechanical damage.

For depth, the IET article reproduces a table from its Code of Practice for electric vehicle charging: 0.5 metres as a general minimum, 0.6 metres on grazing land and 1.0 metre on arable or cultivated ground, measured to the top of the duct. It names Type N450 to BS EN 61386-24 as the minimum duct rating and notes that the IET Solar PV Code of Practice recommends the stronger N750.

DC or AC down the trench? The IET makes a point that matters for solar specifically: armour is an exposed-conductive-part that must be earthed, and on the DC side of an unearthed PV system that relies on double or reinforced insulation, earthed armour “could create a hazardous situation”. DC cables from the panels should therefore have a non-metallic sheath or run in an insulated duct. That leaves two common layouts:

• Inverter in the house. Double-insulated PV cable to BS EN 50618 runs from the array in a buried N750 duct. The run is DC, so the cable must be sized for the string current and the voltage drop.
• Inverter at the array. The inverter sits in a weatherproof position near the frame, and an AC cable, typically steel wire armoured with its armour earthed, runs to the consumer unit. DC isolation then sits next to the array, and the AC circuit is protected and isolated at the house end.

Either way, the new circuit is notifiable electrical work in England and Wales, the installation needs an electrical installation certificate under BS 7671, and a grid-connected system needs a G98 notification to the network operator within 28 days of commissioning if it stays within 16 A per phase.

Distance and voltage drop

Every metre of cable wastes a little power as heat. BS 7671 Appendix 4 gives a guide of 3 percent voltage drop for lighting circuits and 5 percent for other uses on installations fed from the public network; for solar, where every lost watt is lost income, designers usually aim lower.

Worked example: a 25 metre run

This example uses the resistance of copper at 20 °C (about 0.0172 ohm per square millimetre per metre). Warm cables have roughly a tenth more resistance, and an installer will use the BS 7671 tables, so treat the results as a guide.

Array. Four 450 W panels in series. JinkoSolar’s data sheet gives a maximum power voltage of 33.21 V and current of 13.55 A per panel, so the string runs at about 133 V and 13.55 A, 1.8 kW. The cable runs 25 metres each way to the house.

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Two lessons follow. A short, low-voltage string loses proportionally more on a long DC run, so a small garden array 25 metres or more from the house usually needs heavier DC cable or an inverter at the array. And higher string voltages carry power more efficiently over distance, which is one reason larger arrays with planning permission put more panels in series.

Costs as of November 2026

Published ground-mount prices are guide figures from installer and comparison sites, not quotes. These are the ones we found, with the dates the sites show.

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The spread comes from the groundworks. A short run across a lawn to an outside wall is cheap; a long run under a drive or patio, rocky ground, or a frame on a slope adds days of work. Ask for the frame, foundations, trench and cable to be itemised, so you can compare quotes properly.

On VAT, HMRC’s Notice 708/6 zero-rates the installation of solar panels in residential accommodation until 31 March 2027, with 5 percent from 1 April 2027. The notice describes qualifying solar panels as systems installed in, or on the site of, a building, and says nothing specific about arrays on open ground. Ask your installer to confirm in writing how a ground-mounted array within the garden of your home is treated. Panels and frames bought without installation carry 20 percent VAT.

Step by step: planning a garden array

Plug-in solar on a garden stand

A plug-in kit of up to 800 W on a ground stand is a legal alternative in England, Scotland and Wales since 27 August 2026. The government’s Interim Product Specification, made binding by SI 2026/848, lists ground mounting as one of the mounting types a kit may be designed for. The usual limits apply: up to 800 W output, up to 2,000 W of panels in at most four modules, no more than 120 V DC, a moulded 13 A plug, no battery, ENA Type Test Register listing, one device per household and a notification to your network operator. Above 960 W of panels, the maker must advise you to consider a professional assessment of your wiring.

Three points matter in a garden:

• The stand must be part of the kit. The specification requires a manufacturer-supplied mounting system with a structural analysis for UK wind and snow loads, and bans mounting that relies only on cable ties, rope, adhesive tape, bungee cords or straps.
• No extension leads. Extension cables, multi-way adaptors and RCD adaptors are not permitted. The kit’s own lead must reach a socket. Where the inverter and plug are outdoors, the specification requires a socket rated IP55 or better, which for most gardens means an electrician fitting an outdoor socket near the stand. The kit’s instructions must also tell you not to lay its cables in the ground or in wet areas, so a plug-in lead is never buried in a trench.
• Planning. In England plug-in panels on a stand fall under Class B like any stand-alone solar, and may not be fixed to a wooden fence, gate, wall or other enclosure. A one or two-panel kit covers about 2 to 4 square metres, well within 9. Scotland and Wales apply their general stand-alone rules, and Northern Ireland is not covered by the plug-in regulations at all.

A plug-in kit is far smaller than an installed array and normally earns no export payments, but it avoids trenching. Our guides to plug-in solar planning permission and to the best angle and direction for plug-in solar cover the rules and the yields. For brackets and loads, see our guides to mounting plug-in solar on a balcony railing and balcony solar mounting brackets; the same wind-load principles apply to a garden stand.

Common mistakes and edge cases

• Exceeding 9 square metres by one panel. Five standard panels are about 10 square metres, which takes the array outside permitted development in Great Britain. Fix: count panel area before buying.
• Forgetting the Welsh 3 metre limit. A four-panel frame that is fine in England may not be permitted development in Wales. Fix: check every dimension of the array.
• Building too tall near the boundary. A portrait frame on high legs can exceed 2 metres, or 1 metre in front of an English house. Fix: lower the frame or turn the panels to landscape.
• Burying unprotected cable. Bare PV cable or ordinary twin and earth in soil does not meet BS 7671. Fix: use a suitable duct or armoured cable, at depth, with marker tape.
• Putting earthed armoured cable on the DC side. The IET warns this can create a hazard on unearthed PV systems. Fix: double-insulated PV cable in an insulated duct for DC; armour for the AC run.
• Undersizing a long DC run. A small, low-voltage string can lose several percent over 30 metres. Fix: calculate the voltage drop or move the inverter to the array.
• Ignoring winter shade. A frame two metres behind a fence will sit in shadow for weeks around December. Fix: site it as far as possible from southern obstacles.
• Fixing plug-in panels to a timber fence in England. Not permitted development since 27 August 2026. Fix: use the kit’s own ground stand.

Maintenance and durability

A ground array is easier to reach than a roof, which makes cleaning and inspection simple, and harder to protect. Keep grass and plants from growing up in front of the panels, because even low vegetation shades the bottom row of cells. Check the frame bolts and foundations after storms in the first year, and look for animal damage to exposed cables where they leave the duct. Children and pets should not be able to reach DC connectors; covering the cable run where it rises from the ground solves most of that.

Panels on a ground frame age like roof panels: about 1 percent loss in the first year and 0.4 percent a year after that on JinkoSolar’s current warranty curve. The frame and foundations should outlast them if they are galvanised or aluminium and correctly specified. When the array is retired, ground screws and ballast come out cleanly; concrete footings usually stay.

Next steps

• How much electricity a solar panel produces in the UK
• Solar installation in the UK: process, timeline and cost
• Plug-in solar planning permission in the UK