Solar Panel Canopies Installation: How a UK Project Runs

The programme, stage by stage

Durations are deliberately not given as a single figure below, because on a canopy they are set by site-specific facts rather than by the contractor's speed. What is useful is knowing what decides each one, so you can ask the right question at the right point.

Two stages run in parallel with everything else and between them govern the date: the grid connection and the consent. Everything in the construction column can be compressed with more labour. Neither of those two can.

The grid connection: why it is always G99

This is the most consequential error in published canopy guidance, so it is worth being precise. The Energy Networks Association's connection guides split small generation into two routes. G98 covers installations up to 16 A per phase — approximately 3.68 kW on a standard single-phase supply and 11.04 kW on three-phase — and is a connect-and-notify process: you install, then tell the distribution network operator. G99 covers everything above that, and requires the network operator's approval before the system is installed.

A canopy over even a dozen bays is a few tens of kilowatts. Over a hundred bays it is several hundred. There is no commercial canopy that falls inside G98. So any guide telling you that systems below 50 kWp need only a notification has confused the G98 threshold with something else, and if you plan on that basis you will discover the real position at the point where it costs you the most time.

The connection question in full — what decides the timescale, and the five things worth asking the network operator — is in G99 grid connection: what decides the timescale.

What follows from that is the single most useful piece of programme advice on this page: the G99 application costs nothing to start and is almost always the critical path, so it should be submitted as soon as the indicative system size is known. Waiting until the design is finished adds that entire duration to the end of the project. Where the network has no spare capacity at the point of connection, reinforcement may be needed, and that is a different order of time and money — which is why the connection position should be established before anyone commits to a canopy size.

Consent: three different answers in three nations

In England, since December 2023 a canopy above off-street parking at a non-domestic site has had its own permitted development right — Class OA of Part 14 — introduced by S.I. 2023/1279. It is not a free pass: it requires prior approval, the authority has 56 days to determine, glare is assessed in every case, and there are hard limits including 4 m maximum height and a 10 m separation from the curtilage of a dwellinghouse. The conditions and the application content are set out on our solar carport planning permission page.

In Scotland, the equivalent right is Class 9M, with its own limits and a straight exclusion for conservation areas. In Wales, there is no canopy right at all: the Welsh stand-alone non-domestic solar right is capped at 9 m² of panel area, which no car park canopy comes near, so a Welsh canopy is a full planning application from the start. Our solar canopy Wales page sets out what that means for a Welsh programme.

Building Regulations apply in parallel with planning, not instead of it. The exemption that people reach for — Schedule 2 Class 7 — covers a carport open on at least two sides with a floor area of no more than 30 m². A commercial car park canopy is many multiples of that, so it is building work and the Part A structural requirements apply.

Foundations: where the money actually goes

The visible part of a canopy is steel and glass. The part that determines the price is underground. Three things make car parks awkward:

• Made ground. Many car parks are built on fill — former industrial land, demolition arisings, or simply unengineered material under a surface course. Bearing capacity has to be proven rather than assumed.
• Buried services. Drainage runs, lighting circuits, ducting and occasionally live cables sit exactly where the columns want to go. A service trace before design is cheaper than a redesign after.
• Surface reinstatement. Every foundation means breaking out and making good the surface, and the finish has to match. On a resin-bound or block-paved car park this is a visible cost line.

The investigation output decides between pad foundations (a mass of concrete, simple but a lot of excavation), piles (deeper, better in poor ground, more plant) and ground screws (fast and low-arisings, but dependent on ground that will accept them). None is universally right, and a contractor who names the foundation type before seeing ground data is guessing. The structural choices above ground are covered on our commercial solar carport page, and the format comparison for a specific bay layout on our car park solar canopies page.

What the car park goes through

Two honest options exist, and they price differently.

Phased. The works move through the car park in sections, with each section fenced, worked and released. Most bays stay usable throughout. This is what most operating sites need, and it costs more and takes longer because plant is remobilised repeatedly and the working area is constrained.

Closed. The car park comes out of use and the works run continuously. Faster and cheaper per kWp, and viable where there is overflow parking or a seasonal lull. The cost is the parking itself, and that is not a small number: when DESNZ modelled an illustrative 80-space car park it assumed a three-and-a-half-month closure and put the foregone parking revenue at about £180,000 — against roughly £140,000 for the installation, about £28,000 a year of energy savings, about £22,000 a year of charging revenue and about £1,400 a year of maintenance. The lost parking was the largest single figure in the appraisal.

That illustration is not a quote for your site — it is a government worked example with its own assumptions. Its value is the shape it shows: on a revenue-generating car park, the disruption can outweigh the build cost, and a plan that ignores it is not a plan. Cost bands for the installation itself are on our solar canopy cost page.

What the canopy will generate

A canopy is close to horizontal — typically a shallow pitch of around 10 degrees, because a steeper array over parking bays needs more height and more steel. That shallow angle costs some yield against an optimally tilted array, and the loss varies by latitude. Modelled annual output per kilowatt of installed capacity, at a 10-degree tilt, using the European Commission's PVGIS tool:

The spread from Cardiff to Inverness is about 29%, which is large enough that a business case built on a national average figure will be wrong at both ends of the country. Use the figure for the actual site.

Certification, and one widespread misstatement

The Smart Export Guarantee. SEG covers eligible installations up to 5 MW. For solar PV at 50 kW or less, Ofgem asks applicants to show the installation and installer are suitably certified and names MCS as the example, accepting equivalent schemes accredited to EN ISO/IEC 17065. Most commercial canopies are larger than 50 kW. So the flat statement that "a commercial canopy must be MCS certified to get SEG" is not right for the majority of canopies, and the correct step is to confirm with the intended SEG supplier what evidence it requires before making certification a contract condition. It is worth adding that MCS certification is issued against specific technologies — checking a contractor's actual scope in the MCS directory is more informative than accepting the logo.

Electrical work. Certified to BS 7671, with an Electrical Installation Certificate covering the DC and AC elements at handover.

CDM 2015. Two separate triggers, regularly conflated. A Principal Designer and Principal Contractor must be appointed wherever more than one contractor is involved — which is nearly every canopy. Notification to the HSE is a different test: construction work lasting more than 30 working days with more than 20 workers on site simultaneously, or exceeding 500 person days. A project can need a Principal Designer without being notifiable.

Structure. Design to the Eurocodes with UK National Annexes — wind actions to BS EN 1991-1-4, snow loads to BS EN 1991-1-3, steel to BS EN 1993 — with fabrication and erection to BS EN 1090-2 and hot-dip galvanising to BS EN ISO 1461. A canopy is a large, exposed, lightly loaded structure, so wind uplift rather than gravity load usually governs the design, and the site's exposure category matters.

Opaque, transparent or semi-transparent: the glazing decision

Most canopy decks use standard opaque modules, which maximise generation per square metre and are the cheapest option per watt. But a canopy is also a roof over people, and there are sites where daylight underneath matters more than the last few percent of yield. Three constructions are used in practice:

• Opaque framed modules. Conventional glass-backsheet or glass-glass modules on purlins. Highest output per m², lowest cost per watt, and the deck below is in full shade. The default for staff and visitor car parks, where shade is a benefit rather than a problem.
• Glass-glass modules with spaced cells. The cells sit between two sheets of glass with deliberate gaps, so a proportion of daylight passes through. Output per m² falls in rough proportion to the light let through. Used where the space underneath is occupied by people rather than parked cars — entrances, walkways, courtyards, covered seating.
• Thin-film or tinted glazing. Lower output again, but more even light transmission and no cell pattern on the ground. This is the specialist end of the market and the premium is real.

The decision is not primarily an energy one. A car park wants maximum generation and shade; a building entrance or a covered walkway usually wants daylight, and accepts less generation to get it. Where a canopy spans both — a car park that leads to a main entrance — it is normal to specify opaque modules over the bays and a transparent section over the pedestrian route, on the same frame. What matters structurally is that glass-glass units are heavier than framed modules, so the glazing choice has to be made before the frame is calculated, not after.

Two practical cautions. Light transmission figures are a product property, so ask for the specific module's data sheet rather than accepting a percentage quoted for a range. And drainage differs: a deck with gaps between cells is still a sealed roof, but a deck designed to let water through is not — confirm which you are buying, because it changes the gutter and downpipe design and what the surface below has to cope with.

Will canopies be made mandatory on new car parks?

This question drove a lot of UK canopy interest in 2025 and 2026, and the answer is now settled: no. The government consulted on requiring solar canopies on new car parks, and on 21 May 2026 confirmed that the proposal would not be taken any further at this point.

The consultation is still worth reading, for one reason: it contains the only transparent public appraisal of a specific UK car park canopy. For an illustrative 80-space car park, DESNZ used roughly £140,000 to install, about £28,000 a year of energy savings, about £22,000 a year of EV charging revenue, about £1,400 a year of maintenance — and, on a three-and-a-half-month closure, about £180,000 of foregone parking revenue. The disruption was the largest single figure in the government's own case, which is the most useful thing anyone has published about canopy economics.

What follows for a scheme being planned now: there is no regulatory deadline to build against, so the case has to stand on the energy saving, the rates position and whatever the covered parking is worth to you. If a supplier is still selling urgency on the basis of an incoming mandate, that urgency expired in May 2026. The funding routes that do exist are on our solar canopy grants and funding page, and the rating treatment on our solar canopy business rates page.

Six claims to be wary of

What to require of a contractor

A specification tight enough to compare quotes on equal terms, and to make a low price visibly incomplete:

1. Ground investigation before a foundation price. A fixed foundation cost quoted without ground data is a provisional sum with a confident tone.
2. The G99 application submitted at design stage, with the reference and the network operator's response shared as received.
3. Structural calculations for your site's wind and snow loading, signed by the engineer, not a generic type-approval for the product range.
4. A written phasing plan stating how many bays are unavailable, for how long, and what happens if the sequence slips.
5. The consent route named explicitly — Class OA prior approval, Class 9M, or a full application — with who is preparing and submitting it.
6. Separate contract lines for structure, foundations and electrical plant. Useful for comparison, and it matters later: the renewables plant rating exception applies to the generation plant, and the treatment of a canopy's steel frame is not settled, as our solar canopy business rates page explains.
7. Galvanising and warranty terms in writing, distinguishing the panel performance warranty, the inverter warranty and the structural warranty, which are usually three different durations from three different parties.

If you are still selecting suppliers, our solar canopy manufacturers page sets out how UK canopy supply is actually structured and what to ask a fabricator as opposed to an installer. For the structure itself, capacity per bay and the published cost appraisal sit on our solar carport page, and the terminology, yield-by-city and tax position on our solar panel canopy page.

Solar panel canopies installation: questions

Sources

All checked on 26 September 2026.

• Energy Networks Association — G98 and G99 distributed generation connection guides
• S.I. 2023/1279 (inserts Class OA) and GPDO Schedule 2 Part 14
• Building Regulations 2010, Schedule 2 (exempt buildings and work)
• CDM 2015 reg 5 (appointments) and reg 6 (notification)
• Ofgem — Smart Export Guarantee and MCS — SEG certification requirement
• European Commission PVGIS (yields modelled at 10° tilt, crystalline silicon, 14% system loss)
• DESNZ — solar canopies on new car parks consultation (illustrative 80-space appraisal)
• OZEV — Workplace Charging Scheme

This is general information, not engineering or planning advice. This site is published by SEO Dons Ltd; we are not an installer.