The south of England has the best generation in Britain and the most planning constraint. Conservation areas, listed buildings, article 4 directions and dense terraced streets decide more southern solar projects than the weather does, and in London the roof is often not even the applicant's to fix to.
Planning is the southern constraint
Roof mounted domestic solar is generally permitted development, and the exceptions cluster in exactly the places southern housing is: conservation areas, where panels on a slope fronting a highway are commonly excluded; listed buildings, where listed building consent is a separate requirement; and boroughs that have removed permitted development rights through an article 4 direction. Establish the designation of the property before design, because the answer often moves the array to a rear slope, changes the product to solar slates, or requires an application.
Flats, leasehold and who owns the roof
In much of London the roof is common parts owned by a freeholder, so the first question is legal rather than technical: what does the lease say, will the freeholder grant a licence for alterations, and does the managing agent agree. This can take longer than the installation and it is the reason many London flat owners never proceed. Where it works, the connection has to be to your own consumer unit rather than a landlord's supply, which is a design constraint on where the cable runs.
Access in dense streets
Terraced and townhouse stock with no rear access, pavement scaffolding licences from the local authority, parking suspensions, and the sheer height of three and four storey London houses make access a large and variable line. Get it itemised. Two quotes that differ by a lot on an ordinary London terrace usually differ on whether scaffolding, the licence, the parking suspension and making good were included at all.
Generation and shading in a dense city
The south has the best annual generation in Britain, and urban shading takes some of it back: neighbouring buildings, mature street trees and chimney stacks on a Victorian roof all cut into it, and shade in winter is worse because the sun is low. This is the setting where per panel electronics genuinely earn their cost, and where a shading survey across the year is worth insisting on rather than accepting a figure from an aerial image.
Solar panels Southampton and solar panels Portsmouth: the Hampshire ports
The two ports have the best generation figures in the country and a lot of dense Victorian terrace to fit it on. Portsmouth in particular is one of the most tightly built cities in Britain, so the access and scaffolding line above is usually the biggest single variable between quotes, and a pavement licence may be needed. Both cities also have substantial conservation area coverage near the waterfronts, where a slope fronting a highway is the one to check before anything else. Salt air is the third factor, and it decides what the fixings and flashings should be made of rather than whether the job is worth doing.
Solar panels Basingstoke and solar panels Oxford: the Thames Valley and the conservation belt
These two show the split in the southern market. Basingstoke is largely post war and modern estate housing with simple concrete tiled roofs, generous orientation and almost no planning friction, which is close to the easiest case there is. Oxford is the opposite: a very large conservation area footprint, a great many listed buildings, and college and trust freeholds that add a consent nobody budgeted for. In Oxford the first question is what the property is designated as, and listed building consent is a separate application from planning. In Basingstoke the first question is simply which roof slopes where and whether the array is being sized to the house or to the sales target.
Solar panels Surrey and solar panels Berkshire: the commuter counties
Detached and semi detached stock with real roof area, good orientation and enough demand to absorb the generation makes this among the better places in Britain for a domestic array. Two things still decide it. Trees: these are heavily wooded counties, and mature oaks on a boundary put a moving shadow across a south slope for part of the day, which is the case where per panel electronics earn their cost rather than a bigger array. And designation: the Surrey Hills and the North Wessex Downs carry a national designation, and there are article 4 directions in several towns that remove the permitted development right you would otherwise rely on. Check the designation before the quote, not after.
Solar panels in London: the leasehold question comes first
For a flat, and for a great many London houses, the roof is not the occupier's to alter. The lease says who owns the common parts, whether alterations need a licence from the freeholder and what the managing agent's process is, and that answer takes longer to get than the installation takes to do. Start there rather than with quotes, because an installer cannot resolve it and a deposit paid before the licence is a deposit at risk. Where the freehold is yours, the questions become the ones above: conservation area coverage across most inner boroughs, a pavement scaffold licence on a street with no rear access, and shading from neighbouring buildings and street trees.
Questions people ask about solar panel installers London
Do I need planning permission for solar in a conservation area?
Often. Permitted development rights are narrower in conservation areas and panels on a roof slope or wall fronting a highway are commonly excluded. Check the designation and any article 4 direction before design.
Can a London flat have solar panels?
Only with the freeholder's consent, because the roof is normally common parts. Read the lease, expect to need a licence for alterations, and settle how the array connects to your own supply.
Why are London quotes higher?
Access, mostly: taller houses, no rear access, pavement scaffold licences and parking suspensions. Ask for those to be itemised, because a cheaper quote often simply excludes them.
Does urban shading matter much?
Yes, more than most people expect, and worse in winter when the sun is low. A shading survey across the year, and per panel electronics where shade is unavoidable, are worth insisting on.