Just bought a house? Why before you move in is the best time to sort its energy

If you're buying a home and you've half-wondered about solar panels, air conditioning, a heat pump or finally sorting the electrics, there's one window that beats every other: the stretch between getting the keys and actually moving in. An empty house is quicker, tidier and less disruptive to work on than one full of furniture, boxes and people. Here's how to use that window well, and how to keep the money side honest.

Why the empty-house window matters

Most of the mess in a home energy upgrade isn't the kit itself. It's everything around it: lifting floorboards for cable runs, drilling through walls for pipework, turning the power off for a few hours while a fuse board is swapped, getting scaffolding up for the roof. In an empty house none of that matters. Installers can reach every wall without moving a wardrobe, there's no one working from home who needs the Wi-Fi, and any making-good happens before you decorate, not after. Do it a year later and you're dust-sheeting a finished living room and repainting round a new pipe.

To be realistic: plenty of people move in on completion day and don't get a gap at all. If that's you, the next best window is the first few months, before you've decorated. The principle is the same: do the disruptive work first and the pretty work last.

Start with two documents you already have

The EPC. Every home that's sold needs an Energy Performance Certificate, and the second half of it is a list of recommended improvements, each with a rough cost and the rating it could reach. It's a generic list rather than a survey, but it's a free, quick read on where the home is weakest. It also matters for money: some lenders price their mortgages or extra borrowing partly on the EPC rating, so improving it can count for something.

Your survey. If your building survey mentions old wiring, an older fuse board (consumer unit) or no recent electrical certificate, take note. Almost every upgrade here adds load to your electrics, and an EICR (an electrical safety check, typically £150–£300) is the sensible first booking. It's cheap, it tells every later installer what they're working with, and it stops an install day failing because the board can't take it. There's more in can my home's electrics handle air conditioning?

A sensible order of works

Do things in this order and each job leaves the house ready for the next:

1. Electrics first. Get the EICR done, then any consumer unit upgrade it recommends. Everything else plugs into this.
2. Anything that goes through walls. That means air conditioning, which needs pipework between indoor and outdoor units, and an air-to-water heat pump if you're having one, which may also mean larger radiators. These are the messiest jobs, so get them done while the floors are bare.
3. The roof. Solar panels need scaffolding. If you're having any other roof or gutter work done, share the scaffold.
4. Battery and EV charger. These are usually quick once the electrics are sorted, and they're often fitted alongside the solar.
5. Decorate last. Paint goes on after the last hole is drilled, not before.

Which upgrades suit the window best

Air conditioning. A modern split unit is a reversible air-to-air heat pump, so it cools in summer and heats efficiently the rest of the year. Fitting it before move-in means tidy, hidden pipe runs agreed in advance rather than squeezed in around furniture. One honest caveat: if you're not sure which rooms overheat, it can be worth living through one summer first. Then again, top-floor bedrooms and south-facing loft rooms are rarely a mystery. Our honest ‘is it worth it?’ calculator gives you a straight read on your own numbers.

Solar and battery. These are a natural fit for a new home you plan to stay in, because the longer you stay, the more of the payback you keep. Installed solar and batteries currently carry 0% VAT, and that ends on 31 March 2027. It's worth knowing about, but it's not worth panicking over (here's the real maths). For whether the battery earns its keep, see is battery storage worth it?

Air-to-water heat pump. This is the biggest job of the lot. It replaces your boiler, may mean bigger radiators, and needs a hot water cylinder. That makes it exactly the kind of work an empty house suits best. In England and Wales the Boiler Upgrade Scheme grant (£7,500) applies to air-to-water systems fitted by an MCS-certified installer. It doesn't cover air conditioning. For the difference between the two, see air-to-air vs air-to-water heat pumps.

EV charger. If you have, or will soon have, an electric car, the cable run from the fuse board to the driveway is far easier to route through an empty house. See what a home charger really costs.

Paying for it: the honest options

Moving is expensive, and most people don't have a spare £8,000–£15,000 sitting around after the deposit, the stamp duty and the solicitor. So it's worth knowing the main routes. This is general information, not financial advice. We're not mortgage advisers, and we don't arrange finance.

• Savings. This is the cheapest route overall, because there's no interest. If the money's there and you're keeping a sensible buffer, it's the simplest.
• Borrowing against your mortgage. Many lenders offer additional borrowing (sometimes called a further advance) for home improvements. Some also run "green" mortgages, cashback or reward schemes linked to energy upgrades or a better EPC rating. Spreading the cost this way can make the monthly figure small, but it also means paying interest for longer. As a purely illustrative example, £10,000 borrowed over 25 years at 5% works out at roughly £58 a month, which adds up to about £17,500 repaid in total. Products and rates change all the time, and whether it suits you depends on your circumstances. Speak to an FCA-authorised mortgage adviser or your lender. Your home may be repossessed if you do not keep up repayments on a mortgage or any other debt secured on it.
• Be wary of doorstep finance. High-interest finance pushed hard during a sales visit is the expensive way to do this. A good installer will happily quote you a cash price and let you sort the funding yourself.

One practical point: don't let any of this complicate or delay your purchase. Get the house bought first. Borrowing more after completion is a normal, well-trodden route, and a quote from a survey gives your adviser a real figure to work with instead of a guess.

A few things to check before you book

• Flats and leasehold homes usually need the freeholder's permission before anything is fixed to the outside walls or roof. Check your lease.
• Conservation areas and listed buildings have extra rules. See planning permission for air conditioning and for heat pumps.
• Don't decide everything in the stress of the move. Getting quotes in is no-obligation. Booking a survey just gives you a real number to think about, not a commitment.

What to do next

If you're weighing a few of these, start with our cost estimator to get a ballpark for the combination you're thinking about. When you're ready, tell us about the new place below. We'll match you with one vetted local installer, not a bidding scrum, for a free survey and quote, and if your move-in date is fixed, they can tell you straight away whether it's realistic.

General information only, not financial, mortgage or professional advice. Prices are indicative ranges current as of October 2026, and the real figure comes from a survey. Grant and VAT rules can change, so check the current position before you commit.