Most roofs in England are suitable for solar panels. If your roof faces anywhere from east through south to west, is pitched between about 10 and 50 degrees, gets little shade in the middle of the day and has around 20 square metres of clear space, it will almost certainly work. Our PVGIS modelling for Birmingham shows an east-facing roof still making 80% of the output of the best south-facing one, and a west-facing roof 78%.
- 80% and 78% output of east and west roofs compared with south, at 35 degrees in our PVGIS runs
- About 2 square metres per 440W panel, so 10 panels need roughly 20 square metres plus edge clearance
- 200mm maximum projection from the roof slope under permitted development in England
- About 22kg per typical 440W panel, spread across rails and roof hooks
Use the eight checks below to judge your own roof. None of them needs a ladder: most can be done from the garden or on a satellite map. A proper survey, which we do free either in person or remotely from photos and satellite imagery, confirms the details.
Check 1: Which way does your roof face?
South is best in England, but it is not the only good option. We ran PVGIS, the European Commission's solar modelling tool, for 1kW of panels in Birmingham at every common roof direction and pitch. The figures are kWh per kWp per year, with the share of the best result in brackets.
| Roof pitch | South | South-east | South-west | East | West | North |
|---|---|---|---|---|---|---|
| 10 degrees | 879 (91%) | 861 (89%) | 855 (88%) | 808 (83%) | 801 (83%) | 725 (75%) |
| 20 degrees | 931 (96%) | 897 (92%) | 887 (91%) | 802 (83%) | 787 (81%) | 646 (67%) |
| 30 degrees | 963 (99%) | 918 (95%) | 903 (93%) | 789 (81%) | 770 (79%) | 568 (59%) |
| 35 degrees | 971 (100%) | 922 (95%) | 905 (93%) | 780 (80%) | 759 (78%) | 529 (54%) |
| 45 degrees | 970 (100%) | 915 (94%) | 895 (92%) | 753 (78%) | 730 (75%) | 453 (47%) |
| 60 degrees | 930 (96%) | 871 (90%) | 848 (87%) | 691 (71%) | 667 (69%) | 351 (36%) |
What this tells you:
- Anything from south-east to south-west loses less than 10% at normal pitches.
- East and west roofs lose about 20%, less on shallow roofs. West does slightly worse than east in our Birmingham run.
- North-facing roofs make much less, and the penalty grows fast as the roof gets steeper. A shallow north roof can still be worth using; a steep one rarely is.
- The figures scale across England. A south roof makes about 886 kWh per kWp in Manchester and 1,159 in Brighton, and the percentages above hold roughly the same. See our pages on solar panels in Birmingham and Leeds for local figures.
Check 2: What is the pitch?
Most English pitched roofs are between 30 and 45 degrees, which is ideal: in the table, south roofs in that range are within 1% of the best result. Very shallow roofs lose a little in winter, and very steep ones, such as mansard slopes, lose more in summer. You do not need to measure it precisely; the survey will.
Check 3: Is there shade?
Shade matters more than direction. A chimney, dormer, taller neighbouring house or tree that shades part of the roof between about 10am and 3pm will cut output, and more in winter when shadows are long. Stand in the garden at midday and look: if the roof is in clear sun, you are fine.
Partial shade is manageable. Panels can be arranged to avoid the shaded area, and optimisers or microinverters let each panel work independently so one shaded panel does not drag the others down.
Check 4: Is there enough space?
A typical 440W panel measures about 1.76m by 1.13m, which is roughly 2 square metres. Installers also leave clear margins at the edges, ridge and eaves for fixings and wind loading.
Worked example: how many panels fit on a rear roof slope?
- Measure the slope: say 8.0m wide along the gutter and 4.5m from gutter to ridge.
- Allow margins: for this example, take 0.3m off each edge. That leaves 7.4m by 3.9m.
- Across: panels in portrait are 1.13m wide. 7.4 / 1.13 = 6.5, so 6 panels per row.
- Up: each panel is 1.76m tall. 3.9 / 1.76 = 2.2, so 2 rows.
- Total: 6 x 2 = 12 panels x 440W = 5.28kW.
If that slope faces east and the other faces west, you could split the array. Our PVGIS runs show 5 panels (2.2kW) on each face at 35 degrees making 2.2 x 780 + 2.2 x 759 = 3,384 kWh a year, against 4,270 kWh for 4.4kW facing south: about 79% of the south figure, spread more evenly through the day. Our guide to how many solar panels you need helps match the array to your usage.
Check 5: What is the roof covered with?
| Roof covering | Suitable? | What to know |
|---|---|---|
| Concrete interlocking tiles | Yes | The most common and simplest roof to fit. Hooks sit under the tiles, which are refitted over them. |
| Clay plain tiles | Yes | Tiles are thinner and more brittle, so some may need replacing. Allow a little more time. |
| Natural slate | Yes | Slate cracks easily. Fixings go through replacement slates or flashing units at each hook. |
| Metal sheet or standing seam | Usually | Clamps can grip the seams, often with no drilling. |
| Flat roof (felt, EPDM, GRP) | Yes | Panels go on angled frames, fixed or ballasted. The membrane must be in good condition first. |
| Thatch | No | Not suitable for roof-mounted panels. A ground mount may be an option. |
| Asbestos cement sheet | Usually not | HSE lists asbestos cement roof sheeting as an asbestos-containing material. Drilling it releases fibres and needs strict controls, so these roofs, common on older garages and outbuildings, are normally avoided. |
Check 6: Is the roof in good condition and strong enough?
Panels will stay on your roof for 25 years or more. If the roof covering is near the end of its life, or you plan to re-roof in the next few years, do that first: taking panels off and refitting them later adds scaffolding and labour costs you can avoid.
Building regulations require the roof's ability to carry the extra load to be checked and proven, and some roofs need strengthening. In practice most sound pitched roofs take the load comfortably, because each 22kg panel is spread over rails and several hooks into the rafters. Signs worth mentioning at survey: a sagging ridge, slipped tiles, damp patches in the loft, or rafters that have been cut for a loft conversion.
Check 7: Do you need planning permission?
For most houses in England, no. Roof panels are permitted development under the General Permitted Development Order, provided that:
- they project no more than 200mm (0.2m) from the roof slope;
- they do not rise above the highest part of the roof, not counting the chimney;
- on a flat roof, they stand no more than 0.6m above the highest part of the roof;
- in a conservation area or World Heritage Site, they are not on a wall facing a road, and flat roof installations need prior approval of their appearance;
- the building is not listed or a scheduled monument, which need consent.
If you own a flat or leasehold house, you will usually also need the freeholder's permission to use the roof. Our full guide to planning permission for solar panels covers the details and the exceptions.
Standard panels sit well inside the 200mm limit. A typical rail and panel stack on a tiled roof sits far closer to the roof than that, so on an ordinary house the planning question usually comes down to whether the building is listed or in a conservation area.
Check 8: Can your electrics take it?
- Consumer unit. Your fuse box needs a spare way or a small upgrade to connect the inverter safely. Older units may need replacing.
- Space for the inverter and battery. A loft, garage or utility wall usually works. Batteries can be heavy: a Tesla Powerwall 3 weighs 130kg, so it needs a solid wall or floor mounting.
- Grid connection. Systems up to 3.68kW of inverter capacity on a single-phase supply are notified to the network operator after installation. Larger systems need approval first. We handle both.
- Smart meter. To be paid for exported electricity under the Smart Export Guarantee you need a meter that records exports, which in practice means a smart meter.
Roofs that are harder, but not impossible
- Small or cut-up roofs. Dormers, hips and valleys reduce the usable area. Smaller or higher-wattage panels can help.
- Heavily shaded roofs. A garage, extension or outbuilding roof in clear sun may do better than the main roof.
- Businesses and farms. Large barns and industrial roofs are often ideal; see our commercial solar page.
If you are still unsure, the quickest route is a free survey. Send a few photos and your address when you request a quote, and we will tell you what fits, how much it will generate and what it costs, with a fixed written price.
Sources
Orientation and pitch output: our modelling with PVGIS, European Commission Joint Research Centre (Birmingham, SARAH2 radiation data, 14% system losses). Panel size and weight: JA Solar JAM54D40-440 specification. Permitted development: GPDO 2015, Schedule 2, Part 14, the 2023 amendment on flat roofs and Planning Portal. Building regulations: Planning Portal, solar panels and building regulations. Asbestos: HSE, locations of asbestos. Grid connection: MCS, notifying DNOs. Battery weight: Tesla Powerwall 3 datasheet.
