What the evidence shows
Research by the solar industry and some estate agents suggests UK solar installations add between 4% and 14% to property value on average. A 2021 study by MCS found that homes with solar panels sold for approximately £32,000 more than comparable homes without them in the same postcode, based on analysis of Land Registry data.
The uplift varies significantly by region, property type, and system specification. In areas with higher average property values, the absolute increase in sale price tends to be larger. A well-specified, recently installed system with documentation carries more value than an old system approaching the end of its inverter warranty.
The evidence base is still relatively limited — solar homes represent a small share of total transactions — and individual valuers may apply different assumptions. EPC (Energy Performance Certificate) ratings reflect the presence of solar panels, and buyers increasingly use EPC ratings as a filter when searching for homes.
What buyers and surveyors look for
A buyer or their surveyor will ask for: MCS installation certificate; panel brand, model, and warranty documents; inverter make, model, and remaining warranty period; roof structural survey (if available) confirming the roof can support the panel weight; details of any roof penetrations and whether they have been properly waterproofed; and Electrical Installation Certificate.
A system where documentation is complete commands a higher uplift than a system where the installation paperwork has been lost. An inverter at or near the end of its warranty period, or from a manufacturer that has ceased trading, can be a negative factor — buyers may discount the price to account for expected replacement costs.
If the installation was on a leased roof or involved a solar lease or Power Purchase Agreement (PPA) — common before 2015 — this can significantly complicate a sale and in some cases reduce property value. A fully owned installation (no lease, no PPA) is straightforwardly positive from a sale perspective.
Remortgaging with solar panels
Most major UK lenders treat solar panels as a fixture of the property and factor them into the valuation. There is no mainstream lender that will refuse to mortgage a property solely because it has solar panels, though some valuers may be conservative in how much additional value they attribute.
The more important consideration for remortgaging is structural: lenders require confirmation that roof penetrations are watertight and that the installation does not compromise the building's structure or insurance. Your buildings insurer should have been notified at installation — if they were not, correct this before remortgaging.
Protecting the uplift
The main threats to value uplift are: an ageing or failing inverter; missing documentation; a panel array in poor condition; or evidence of inadequate maintenance (significant soiling, bird damage, corrosion).
Annual professional cleaning maintains panel condition visibly — a clean, well-maintained array on a viewing impresses buyers in a way that a grimy, neglected one does not. Keeping the monitoring portal connected and active, and downloading annual generation summaries, gives buyers evidence that the system has been performing as expected.
Before listing a property, a professional clean and a quick review of available documentation — ideally assembled into a single handover folder — is the simplest way to maximise the value a buyer and their surveyor will attribute to the installation.