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Most commercial solar installations don’t require planning permission as they’re typically covered under permitted development rights (the same rules that let you swap out your windows without council approval).
That said, every system still needs to be registered with your local network operator. Larger systems also require formal approval before installation can begin.
In this guide, we’ll explain what applies to your building, what OVO takes care of for you, and what to expect at each stage.
Do commercial solar panels need planning permission?
For most standard commercial buildings in England, Wales, and Scotland — no.
Rooftop solar panels fall under permitted development rights, provided they meet a few basic conditions:
• Panels on a flat roof must not extend more than 1m above the roof surface
• Panels on a pitched roof must not protrude more than 200mm from the roof slope
• The installation must not be on a wall or surface that faces a motorway
• Panels must be removed when they're no longer needed
Here's a quick reference for common building types:
| Building type | Planning permission needed? | Notes |
|---|---|---|
| Standard commercial building (office, warehouse, retail) | No | Falls under permitted development |
| Listed building | Yes — listed building consent required | Apply to local planning authority |
| Conservation area — roof not visible from motorway | Usually no | Check with your local authority to confirm |
| Conservation area — roof visible from motorway | Likely yes | Permitted development rights may not apply |
| Ground-mounted system (over 9m²) | Usually yes | Separate permitted development thresholds apply |
| System over 1MW | Yes — different approval process | Contact OVO's commercial solar team for guidance |
If your building falls into one of the exception categories, that doesn't mean solar is off the table, it just means an extra step. OVO's commercial survey identifies any planning requirements before you commit to anything.
Scotland and Wales: are the rules different?
Broadly similar, with minor differences. In Scotland, permitted development rights for commercial solar follow the same logic as England for most properties. In Wales, the rules align closely with England's. If your property is in a National Park or Area of Outstanding Natural Beauty, additional restrictions may apply in any nation.
OVO's team will check the specific rules for your local authority as part of your free survey.
DNO applications: G98, G99, and G100
Before connecting to the grid, your Distribution Network Operator (DNO) must be told. The DNO is the company that manages the electricity network in your area, not your energy supplier.
The process depends on your system size:
| System size | Approx panels | Application type | What's required | Typical timeline |
|---|---|---|---|---|
| Up to 3.68kW | Up to 8 panels | G98 — notify after install | Notification sent within 28 days of connection | No delay to installation |
| 3.68kW to 1MW | 9 panels to ~2,270 panels | G99 — apply before install | Full technical application with system design | 6 to 12 weeks for approval |
| Over 1MW | 2,270+ panels | G100 — detailed application | Complex technical submission, often with network studies | 3 to 6+ months |
Panel counts based on 440W panels. The G99 range covers everything from a small commercial rooftop to a large industrial site.
The vast majority of SME (small and medium size enterprise) commercial systems fall under G99. OVO submits the G99 application as soon as your system design is agreed so you don't need to wait until after installation to start the process.
G99 applications can take 6–12 weeks for approval. OVO submits applications promptly and manages all communication with the DNO so you won't need to be involved directly.
Got questions about what applies to your site? OVO's commercial team checks planning and DNO requirements as part of your free survey — before you commit to anything.
What are the building regulations for commercial solar?
Planning permission and building regulations are different things. Planning permission is about whether you're allowed to build something. Building regulations are about whether it's built safely.
Commercial solar installations must comply with:
• Part P (electrical safety): all electrical work must be carried out by a qualified electrician
• Structural loading requirements: the roof must be confirmed capable of bearing the weight of the panels and mounting system
• Fire safety: particularly relevant for flat-roof installations where panels sit close to roof-level plant
For most standard commercial roofs, structural sign-off is straightforward. OVO's installations use ballasted mounting systems on flat roofs which spread the load without penetrating the roof membrane, which simplifies structural approval significantly.
If your roof has any existing structural concerns, OVO's survey will identify them before installation begins.
MCS certification — what it is and why it matters
MCS stands for Microgeneration Certification Scheme. It's the quality standard that proves your solar system was designed and installed to the required technical specification.
MCS certification isn't optional; it's required to access the Smart Export Guarantee (SEG) payments for electricity you export to the grid. Without it, you can't register for export income.
OVO's commercial installations are fully MCS-accredited. We handle certification as part of the installation process so you don't need to arrange it separately.
How OVO handles compliance for you
Here's everything OVO manages on your behalf as part of a commercial solar installation:
| Compliance item | OVO handles this? | When |
|---|---|---|
| Planning permission check | Yes | During free survey stage |
| G99 DNO application | Yes | Submitted after system design is agreed |
| DNO liaison and queries | Yes | Throughout the approval period |
| Part P electrical sign-off | Yes | On installation day |
| Structural load assessment | Yes | During survey |
| MCS certification | Yes | Within one week of installation |
| SEG tariff registration | Yes | Runs concurrently with installation |
From your side, the process is: agree to a survey, review the quote, pay, and sign off on the design. OVO handles the rest.
Book OVO's free commercial solar survey. We'll check planning, DNO requirements, and structural suitability for your specific site, with no commitment from you.