In most cases, no. Solar panels on a house count as permitted development, which means you can have them installed without applying for planning permission at all. The great majority of the domestic installations we carry out across Lincolnshire go ahead with no application of any kind.
Four situations change that answer, and they are worth checking before you get as far as a quote. A listed building never has permitted development rights for panels. A property in a conservation area cannot have them on a wall fronting a highway. A ground mounted array has its own much tighter limits. And on any house, panels that would sit above the ridge line or stand too far off the roof fall outside the rules. Everything else is normally straightforward.
What permitted development actually allows
The national limits are specific, and they are the ones your installer should be working to. On a pitched roof, panels must project no more than 200mm from the roof slope, and no part of the installation may sit above the highest part of the roof, with the chimney discounted. On a flat roof, the highest part of the equipment must be no more than 600mm above the highest part of the roof, again discounting the chimney. There is also a tidy little condition that equipment should be removed once it is no longer needed.
That 200mm figure is more generous than it sounds for a standard on-roof system, where the panel sits on rails a few centimetres above the tiles. It is not generous at all if somebody proposes tilting panels up on a pitched roof to improve the angle, which is a good way to turn a straightforward job into a planning application for very little extra yield.
The 600mm flat roof limit is the one that occasionally bites, because a ballasted frame tilted to catch the sun stands proud of the roof in a way an in-plane installation does not. It is a real constraint on a flat roofed home like the 6.8kW system we installed in Lincolnshire, and it is worth knowing about before the frame is specified rather than after.
Listed buildings are the clear exception
Permitted development rights for solar simply do not apply to a listed building. You need listed building consent from the local planning authority, and that is a separate consent from planning permission rather than a version of it.
The part that catches people out is the wording about the grounds. Panels must not be installed on a building that is within the grounds of a listed building. So the detached garage, the outbuilding or the barn that nobody thinks of as listed is very often covered by the listing of the main house. If the house is listed, assume everything in the curtilage is too until the planning authority tells you otherwise.
None of this means the answer is no. Plenty of listed properties get consent, particularly where panels go on a rear slope or an outbuilding out of public view. It means the timeline is longer and the outcome is a decision rather than a formality.
Conservation areas, and what actually gets refused
In a conservation area or a World Heritage Site, the rule is that panels must not be fitted to a wall which fronts a highway. Roof slopes are treated more leniently than walls, which surprises people who assume conservation area means no panels anywhere.
In practice the sensible move is almost always to design around the constraint rather than argue with it.
In our experience, using a rear or side roof slope works better than applying for permission on a highway facing elevation, because a determination takes roughly eight weeks with no guaranteed outcome, and where the alternative slope still sits within about 45 degrees of south the generation you give up is usually low single figures rather than the fifteen to twenty per cent a true east or west facing roof would cost you.
Conservation area policy is also interpreted locally, and two authorities can take different views on the same roof. We check with the planning authority rather than relying on a general reading of the rules, because a five minute conversation at the start is worth a great deal more than an assumption at the end.
Ground mounted arrays have their own limits
This is where permitted development is much tighter than most people expect, and where we most often have to correct an assumption.
For a stand-alone installation in the grounds of a house, only the first one counts as permitted development. It must be no higher than four metres, and no higher than two metres in a conservation area. It must sit at least five metres from the boundary. And the array must be no more than nine square metres, which the rules describe as three metres wide by three metres deep. It cannot go within the boundary of a listed building or a scheduled monument, and in a World Heritage Site it must not be nearer the highway than the house is.
Nine square metres is about four panels. That is a useful trickle, not a system that runs a house, so anyone imagining a row of panels along the bottom of the garden is already outside permitted development and into an application.
At agricultural scale the question does not really arise, because a ground mounted array of any consequence is a planning application from the outset. The 30.24kW array we built for a poultry farm near Friskney, being 72 panels of 420W, is in a different world from a nine square metre domestic exemption. On a working farm that is the normal route and it is well trodden, but it is a planning process rather than a permitted development one.
Planning is not the only permission involved
Even where no planning application is needed, the installation still has to satisfy the Building Regulations. The roof has to take the additional load, and the electrical work has to comply with BS 7671. An MCS certified installer notifies building control on your behalf, which is one of the practical reasons certification is worth having beyond the export tariff eligibility.
Your distribution network operator also has to be told, either notified after the event for a smaller system or asked for approval beforehand on a larger one. That is the installer's job as well, and none of it involves the planning department.
What this looks like across Lincolnshire
The county throws up the full range. There are conservation areas in the market towns, a good deal of listed stock, and enough rural plots that the ground mount question comes up far more often than it would in a city. Around Horncastle in particular the listed building question is a live one rather than a technicality, and it pays to establish the position before anyone measures a roof.
New build is the easy end. On a development like the thirteen plot eco bungalow scheme at Burton Waters, the panels formed part of the approved scheme from the start, so there is no separate consent to chase. That is generally true of new housing now, since solar is designed in rather than added later.
The awkward end is a period property on a village street where the only good roof faces the road. That is where the conversation about slopes, output and whether an application is worth making actually happens, and it is a big part of whether the numbers work on a particular house.
How we handle it
We establish the planning position before quoting, not afterwards. It takes a check of the listing and conservation area status and, where there is any doubt, a call to the local authority. A quote that ignores the question is not really a quote, because the answer can change the design, the price and the timeline.
Where an application is genuinely needed we will say so plainly, including when our honest view is that the likely outcome does not justify the wait. Any installer worth using should be doing the same rather than leaving you to discover it.
Talking to us about your roof
If you are unsure whether your property is listed or sits in a conservation area, that is worth resolving early and it is quick to check. Tell us the address and roughly which way the roof faces and we can tell you where you stand before anyone commits to anything.
Get in touch and we will look at it with you.
