Solar roof tiles: what they are, what they cost and when they make sense

Solar roof tiles (and solar slates) are small solar units that take the place of ordinary tiles or slates, so the roof looks close to a normal one. The catch is power per square metre: the two UK products we checked fit about 138 to 193 watts on each m² of roof, against about 220 W for a standard 440 W panel. So a tile roof needs more space for the same system, and the makers' own figures put tiles above panel systems in price per kW. They make most sense when you're re-roofing or building anyway, or where the look of the roof matters most.

What counts as a solar tile

Three different things are sold under similar names, so first ask which one you're being offered.

• Tile- or slate-sized solar units. Each unit replaces a few tiles or slates and is fixed to the roof battens like them. GB-Sol's PV Slate looks like a row of four natural slates; SolarTyle's tiles are designed to sit among concrete tiles.
• Full-size in-roof panels. Standard-size panels fitted into the roof instead of on top of it. Some are sold under "tile" names: Marley's SolarTile is a 445 W panel of 1,722 × 1,134 mm. In-roof solar panels covers these.
• On-roof panels in a dark finish. Ordinary panels on brackets. They aren't tiles, however discreet they look.

Two UK solar tile products, side by side

We read the datasheets and certificates for two tile-sized products sold in the UK, and set a standard on-roof panel beside them for comparison.

Sources: GB-Sol PV Slate brochure (December 2023 version), SolarTyle datasheet (v3, 2025) and MCS certificate (July 2025), JinkoSolar datasheet (F1.3-EN).

GB-Sol's slates come in light grey only, and the maker says two natural slates are needed around every edge and roof feature. SolarTyle's certificate covers its modules under MCS 005; ask how the roof-kit side is certified or evidenced, because the MCS installation standard requires MCS 012-certified kits for panels integrated into pitched roofs, or extra evidence where none suits.

How much roof space tiles need

Here is roughly how much roof a 4 kWp system covers with each product, before edges, gaps and obstacles.

The unit areas come from the datasheets: 1,009 × 200 mm of visible PV Slate, 1,500 × 345 mm of installed SolarTyle tile at a 22° pitch, and 1,762 × 1,134 mm for the panel. If your usable roof is small, a tile roof may mean a smaller system. For new homes in England, Approved Document L (from 24 March 2027) measures on-site generation against panels of 0.22 kWp per m², which a 138 W/m² product can match only over about 60% more area (0.22 ÷ 0.138 = 1.59).

How much a tile roof produces

A kWp of solar tiles produces roughly what a kWp of panels does on the same roof slope, minus a little for heat: built into the roof, with less air behind them, solar units run warmer. In the European Commission's PVGIS model, fully building-integrated modules in UK cities produce about 3% less a year than free-standing ones (our runs, 35° facing south, 14% losses); your installer's MCS performance estimate should give the figure for your roof and product. For a 4 kWp roof facing south in Birmingham, that is 4 × 968 = about 3,870 kWh a year free-standing and 4 × 940 = about 3,760 kWh fully integrated, as long-term averages. The direction of your roof matters far more than the product: in the same model, an east-facing roof in Birmingham produces about 20% less than a south-facing one.

What solar roof tiles cost

There's no official price series for solar tiles. Here is what we could find, with the date we read each figure or the maker last reviewed it:

• Ordinary panels (official figure). DESNZ figures for MCS-certified systems up to 4 kW on existing homes in Great Britain averaged (mean) £2,109 per kW of panel capacity in 2025/26, including VAT and excluding batteries. That's about 4 × £2,109 = £8,435 for 4 kWp: a reference point, not a quote.
• GB-Sol (maker, read 24 September 2026). Its product page says a 4 kWp PV Slate system with SolarEdge optimisers typically costs "about one and a half times the price of a cheaper system with large solar panels & optimisers, allowing for the savings where PV Slates replace other roofing materials".
• SolarTyle (maker, reviewed 13 August 2026). Its indicative comparison puts its tiles at about £1,500 per kWp (about £6,000 for 4 kWp) and a premium conventional in-roof system at about £1,250 per kWp. The maker calls these indicative figures, not a quote. It says VAT, the inverter and electrical connection, and scaffolding should be confirmed in a project quotation, and that roof stripping isn't automatically part of the comparison. So they aren't directly comparable with the DESNZ figure.

What moves the price most is whether the roof is being replaced anyway. Tiles or in-roof panels take the place of some roofing you'd otherwise buy, so ask for three priced options for the same roof: keep the roof and add on-roof panels; re-roof with in-roof panels; re-roof with solar tiles. For each, divide the solar price by the kWp, and check the MCS performance estimate for the kWh a year. Solar panel cost explains what a panel quote should include.

VAT. Solar supplied and fitted by the installer in your home currently has 0% VAT. This is scheduled to rise to 5% on 1 April 2027 unless extended. Solar tiles bought without installation carry 20% VAT. When it comes with a re-roof, HMRC's rules on single and mixed supplies decide how each part is taxed, so ask the installer to show the VAT on the roofing and solar parts separately. VAT on solar panels has the detail.

Planning, listed buildings and building regulations

Solar tiles don't get round planning rules. They sit flush, so they usually fit within the permitted development limits for pitched roofs, but the exclusions still apply.

• Listed buildings. Permitted development doesn't cover them (in Northern Ireland, only once listed building consent is granted). In England, any change affecting a listed building's character needs listed building consent, however discreet the product.
• Conservation areas and World Heritage Sites. In England, pitched-roof panels in a conservation area are permitted development. In Scotland they aren't in a World Heritage Site, and in a conservation area they aren't on the front of the house or on a side that faces a road. In Northern Ireland, a conservation area or World Heritage Site rules out a roof slope that faces, and can be seen from, a road. Councils can also remove these rights locally (in England, by an Article 4 direction).
• Re-roofing. In England, if more than half a roof is stripped back to the rafters, Approved Document L says the whole roof should be brought up to current insulation standards where technically, functionally and economically feasible (a 15-year simple payback is the economic test). Budget for it.
• Fire. Tiles form the roof covering, so they need a fire rating suited to their distance from the boundary; in-roof solar panels explains the rule, and planning permission for solar panels gives each nation's limits.

Warranties, repairs and export payments

• Warranties. Product warranties on the two tiles above differ by ten years, so read the product, output and weatherproofing terms for the exact product.
• Who fits it. GB-Sol's product page (read 24 September 2026) says your roofer can fit its slates under GB-Sol's supervision, with GB-Sol doing the wiring, at a similar speed and cost to the natural slates they replace. Ask who is responsible for leaks and for replacing a failed unit, as that means working on the roof covering.
• Export payments. To get paid for exported electricity under the Smart Export Guarantee (Great Britain only), systems up to 50 kW need MCS certification or an equivalent for the installation and the installer. Check both before you sign; see the Smart Export Guarantee.

Are solar roof tiles worth it?

They can be when most of these apply:

• The roof is being replaced or built, so the tiles replace roofing you'd pay for anyway.
• The look of the roof matters to you, or to the council on a listed building.
• The roof has enough area for the system you want at the product's lower power per m².
• The quote shows a clear price per kWp, an MCS performance estimate and warranties you're happy with.

If your roof is sound and your aim is the most electricity for your money, get a price for on-roof panels too, and for in-roof panels if you're re-roofing, and compare them on the same basis; comparing solar quotes shows how.

Frequently asked questions

How much do solar roof tiles cost in the UK?

There are no official figures. One maker's indicative price is about £1,500 per kWp (August 2026). It says VAT, the electrics and scaffolding should be confirmed in a quote, and roof stripping isn't automatically included, so it isn't comparable with the DESNZ figure for ordinary panel systems up to 4 kW on existing homes, which includes installation and VAT: £2,109 per kW in 2025/26. Both makers' own comparisons put tiles above panel systems.

Are solar tiles as efficient as solar panels?

Per square metre, no: the two products we checked give about 138 and 184–193 W per m², against about 220 W for a standard 440 W panel. Per kWp installed, their yearly output is similar, less about 3% in the European Commission's PVGIS model for fully roof-integrated modules, because they run warmer.

Do solar roof tiles need planning permission?

Usually not on a house that isn't listed, as they sit within the pitched-roof permitted development limits. Listed buildings need consent, and some areas have had permitted development rights removed. In Scotland, permitted development doesn't apply in a World Heritage Site, or in a conservation area to the front of the house or a road-facing side; in Northern Ireland's conservation areas it excludes a roof slope that can be seen from the road it faces.

Can you add solar tiles to an existing roof?

Only by removing the tiles or slates where they go, so they're usually fitted during a re-roof or new build. On a sound roof, on-roof panels are the simpler route.

Can I get the Smart Export Guarantee with solar tiles?

Yes, in Great Britain, if the installation and installer have MCS certification or an equivalent. Northern Ireland has no Smart Export Guarantee; ask your electricity supplier what it pays for exported electricity.