How to cool a UK home: the complete, property-specific guide

British homes were designed to hold heat in, not let it out. For most of their history that was the right call - and for the summers we now get, exactly the wrong one. A well-insulated flat can sit above a comfortable temperature for days at a time, and no amount of willpower with the windows fixes it. If your home overheats, the honest answer is not a single product you can buy off a shelf. It depends on your property: its floor and roof, its fabric, its heating, and where it sits. This guide walks through the whole decision, then points you to a free check that runs it for your actual address.

Why UK homes overheat

Overheating is a fabric-and-position problem before it is a weather problem, and it looks different in every home type. A top-floor flat takes the roof's heat all afternoon with nothing above to buffer it. A solid-brick Victorian terrace stores heat in its masonry through the day and radiates it back overnight, so the house is often hottest at 11pm. A new build's airtightness traps the heat that gets in. A loft conversion sits directly under the roof with almost nothing between the plasterboard and the tiles. We break each of these down, with real per-borough data, in our archetype guides - for example best cooling for a top-floor flat in Islington - and the modelling behind them follows CIBSE TM59, the same overheating standard that Building Regulations Part O now applies to new homes.

Your cooling options

There are two families of answer. Passive measures - external shading, better glazing, night ventilation - lower the heat coming in, and they are always worth doing first. Active cooling - air conditioning, or an air-to-air heat pump that cools in summer and heats in winter from the same unit - removes heat that is already inside. For most genuinely overheating UK homes the practical fix is active, room-by-room cooling; passive measures help at the margins but rarely rescue a top-floor or loft room on their own. If you are weighing the low-carbon options, our guide to air-to-air versus air-to-water heat pumps explains why air-to-air is usually the one that actually cools.

What it costs, and the one honest grant route

An air-to-air heat pump for a room or two is typically a low-thousands job installed; a single-split air conditioning unit for one hot bedroom is a little less. There is one route to public funding, and it is worth being precise about it, because most sales pages are not.

You are eligible for the £2,500 air-to-air grant (Boiler Upgrade Scheme) only when the heat pump replaces your fossil-fuel or electric heating and is fitted by an MCS-certified installer. If you keep your boiler and add cooling as an extra, that is a cooling-only add-on, and it is not eligible for the £2,500 grant, whatever your heating type - a private-pay air conditioning unit is an F-Gas / REFCOM job, not MCS. The word that decides it is replace. Our honest guide to the £2,500 grant walks through both branches in full. (Grant rules as of August 2026 and subject to change.)

Planning permission and conservation areas

Flats and conservation areas are where this trips people up. The permitted-development rights that let a house fit an outdoor condenser do not apply the same way to flats, and inside a conservation area an external unit on a front or side elevation usually needs planning permission. This varies enormously by borough: our records indicate 37.7% of top-floor flats in Islington sit inside a conservation area (as of July 2026, from planning.data.gov.uk and Historic England), against a much lower share in a lot of outer London. It is very doable - councils across the country approve these every week - but it is a step to plan for, not a formality.

How we work this out

Every figure here comes from public property data and a documented method: CIBSE TM59 and Part O for overheating, gov.uk for the Boiler Upgrade Scheme, and MCS and F-Gas / REFCOM for installer accreditation. We show our working rather than ask you to trust a logo. You can read the full methodology and sources here.

Check your own home

Every home is different - your floor, aspect, EPC, heating type and conservation status all move the answer. Our free cooling checker pre-fills your home from public property data (EPC and UPRN records) and gives you a property-specific verdict on screen, straightaway: your overheating score, the right system, your real grant eligibility, the planning position and a net cost. No phone call, no waiting.

Check your home in 60 seconds ▸

You will see your full cooling plan instantly. If you would like us to email it to you, or to have a single vetted local installer contact you about a free survey, you choose that at the end - we only get in touch if you ask us to.