How old Scotland's homes are
Scotland's housing is older than many people assume, and a large share of it is built from stone. The Scottish House Condition Survey for 2024 puts 17% of homes as built before 1919 and 7% as pre-1919 tenement flats (Scottish House Condition Survey 2024). The table sets those figures beside the wider stock.
| Group | Share of Scottish homes | What it means for panels |
|---|---|---|
| Built before 1919 | 17% | Old timbers and slate; roof condition and structure need checking |
| Pre-1919 tenement flats | 7% | Shared roof, several owners, often in a conservation area |
| Tenement flats of any age | 23% | Roof ownership and agreement come before anything else |
| Flats of any kind | 35% | Building warrant more likely; roof space may be limited |
| EPC band C or better | 56% | The rest may gain more from insulation first |
Source: Scottish House Condition Survey 2024, housing stock and key findings. The census counts households rather than homes and puts the share living in flats at 32.4% (Scotland's Census 2022).
Age alone does not rule a home out. A sandstone villa with a sound slate roof facing south can be a better prospect than a modern house under a shady tree. What age does is raise the number of things to check, and it brings planning protections into play more often.
Thermal performance is worth a thought too. Solid stone walls lose heat differently from cavity walls, and many older homes sit below EPC band C. Panels make electricity; they do not keep heat in. If the house is hard to heat, the Home Energy Scotland advice service can help you weigh insulation or heating work against panels, at no charge.
Slate roofs and roof condition
Most older Scottish roofs are natural slate. Slate is long-lasting but brittle, and fixing anything to it takes care. Panel rails are held on brackets that reach down to the rafters, so each bracket has to pass through or between the slates. A careful firm will explain how it handles that: which slates it lifts or replaces, how it seals each fixing, and what it does about any slate that cracks. Ask for that in writing.
Many Scottish slate roofs are laid on sarking, timber boards fixed over the rafters, rather than on open battens. Sarking stiffens the roof and gives a solid base, but it also hides the rafters, so the firm should confirm where the fixings will land and how it has checked the timbers beneath.
Then look at the roof's age and condition, honestly. Panels are expected to last 25 years or more, and an inverter around 12 years (Energy Saving Trust). If the roof will need serious work within that time, do it first. Warning signs include:
- slates slipping or held on with metal clips, often a sign that the original nails have corroded;
- damp patches or daylight showing in the roof space;
- worn lead in valleys, around chimneys or at the ridge;
- sagging along the ridge or between rafters.
Taking panels off to repair a roof, then putting them back, costs money and risks damage to both. If the roof is due for work, one set of scaffolding for the roof repair and the panels together is the sensible route.
Chimney heads, skews and shade
Older Scottish roofs tend to carry more than modern ones: tall chimney heads, stone skews along the gables, dormers and roof lights. Each one affects where panels can go.
- Shade. In Scotland the sun stays low for much of the year, so a chimney head can throw a long shadow across a roof slope in the morning or afternoon. Panels in that shadow produce less, and depending on how they are wired, can drag down their neighbours.
- Condition and access. Chimney heads need repointing, new copes and new flashings from time to time. Panels laid tight against a chimney can make that work harder. Leave room for access, and think about getting chimney repairs done first.
- Skews and edges. Stone skews and exposed gables catch the wind. Panels are usually kept back from roof edges, which reduces the usable area on a narrow slope.
- Dormers and attic rooms. Common in older Scottish houses, they break up the roof and leave smaller, awkward areas for panels.
A good design shows where each panel sits and what shades it through the year. If a quote only gives a panel count, ask for the layout.
Cables, inverters and thick stone walls
The panels are only part of the job. Cables have to get from the roof to the inverter, and from the inverter to the consumer unit, and in an older house that can mean drilling through thick, solid stone. Ask where each cable will run, where the inverter will sit, and how any holes in stonework will be sealed against damp. In a conservation area, a cable run down the front of a sandstone terrace may draw more attention than the panels themselves, so a route through the roof space or down a rear wall is usually the better choice.
Listed buildings, World Heritage Sites and conservation areas
Older homes are far more likely to carry planning protections, and these change the rules for solar.
Listed buildings and World Heritage Sites. Class 6HA, the permitted development right for solar on homes, is unavailable for a listed building, for land within a listed building's curtilage, and for homes in a World Heritage Site such as Edinburgh's Old and New Towns (the order, Part 1A). Panels there need a planning application. Ask the council's planning team whether listed building consent is needed as well, and talk to them before spending money on a design.
Conservation areas. Class 6HA still applies in a conservation area, but not to panels on the principal elevation or on a side elevation that fronts a road (the order, Part 1A; Circular 1/2024). In practice, that usually points to a rear slope. If the only good slope faces the street, you will need to apply.
Everywhere, panels must be removed once they are no longer needed. The planning permission guide covers Class 6HA in full, including the limits on how far panels may stand proud of the roof.
Outbuildings and the garden
When the house roof is protected, shaded or too fragile, there may be other places to put panels. The Scottish order has separate classes for them (the order, Part 1A):
- Class 6HB covers solar on outbuildings such as a garage or shed, with a limit on how far panels can stick out, and not in the front curtilage of the house.
- Class 3B covers ground-mounted panels, provided they are not forward of the principal elevation, keep within a height limit, and are not in a conservation area or the curtilage of a listed building.
A sturdy stone outbuilding or a sunny corner of a garden can sometimes do better than a cluttered main roof. Check the conditions for your home with the council before committing.
When a building warrant comes in
If the roof needs strengthening to carry panels, that work needs a building warrant. West Lothian Council's published guidance says roof panels on a single or two-storey house need no warrant if the existing roof can take the load, but that strengthening does need one, and that alterations to flats need a warrant too (West Lothian Council). That is one council's guidance; ask your own building standards team.
Older roofs are where this comes up most. The building warrants guide explains the process, and the tenements and flats guide covers shared roofs. When you compare quotes, the guide to choosing an installer explains what a sound quote for an older roof should spell out. Roof repairs, slate replacement and scaffolding all add to the price, so make sure every quote covers the same work; the cost guide shows what Scottish households paid per kW for the panels themselves in the latest official data.