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Islington · cooling guide

How to cool a new build in Islington

Written by Solomon Amos.

Sources: CIBSE TM59, Building Regs Part O, gov.uk Boiler Upgrade Scheme, and MCS (the certification scheme for registered installers) - see methodology

Last checked against current grant rules on 14 August 2026

Quick answer

Overheating risk for the typical Islington new build is moderate, so the usual fix is air-to-air heat pump, about £2,800-£3,220 installed. An air-to-air heat pump replacing qualifying fossil-fuel or electric heating can attract a grant through an accredited installer; kept alongside your boiler it is private-pay. Check your address for the exact verdict.

New builds are rare in Islington, with just 415 on the EPC register, but their lightweight modern construction gives them less thermal mass than the borough's older stock, so they warm up fast in hot weather. At a median floor area of 63 square metres, the cooling choice that suits them often differs from what works in a Victorian house.

Struggling to keep your Islington new build cool once the heat sets in? You are far from the first to notice - and although new builds are a smaller share of the borough (about 415 homes, 0.3%), they overheat about as reliably as any home type here. On our overheating scale a typical Islington new build lands near 53 out of 100 - "moderate" - meaning the fan-and-open-window routine stops coping once real heat arrives. This page gives you the property-specific answer instead: which cooling system suits your home, the real cost, and whether planning permission comes into it - before any installer visit.

Why new builds in Islington overheat

The very things that make a new build efficient in winter are what trap heat in summer. Airtightness and thick insulation stop warmth escaping in the cold months, and stop it escaping just as effectively once the sun is doing the heating instead of the boiler - so solar gain through large glazing and everyday internal heat have nowhere to go. A single-aspect flat cannot draw a cross-breeze to help matters. The problem is recognised enough that Part O of the Building Regulations now directly limits overheating in new homes. Insulating further would only make the problem worse; what actually helps is mechanical cooling, ideally from a unit that heats efficiently in winter too, given how many of these homes have no gas connection to begin with. For a typical Islington new build, the median floor area is around 63 sqm - over that footprint of sealed, airtight construction, the trapped heat described above has nowhere to go once the windows are shut.

New builds in Islington: by the numbers

0% of Islington homes are new builds

415 of 133,333

63 m²

median floor area

£192

median annual heating cost

EPC band distribution

415 new builds in Islington with an EPC on record

0%
61%
36%
3%
0%
0%
0%

Greener bands are more energy-efficient; red bands (E-G) are poorer-fabric homes that trap summer heat.

EPC band distribution for new builds in Islington
EPC bandHomesShare
A00%
B25561%
C14936%
D113%
E00%
F00%
G00%

When these homes were built

Construction era of 68 new builds in Islington

  • pre-1919 29%
  • 1919-1944 7%
  • 1945-1999 10%
  • 2000+ 53%
Construction-era mix for new builds in Islington
EraHomesShare
pre-19192029%
1919-194457%
1945-1999710%
2000+3653%

Real EPC and property-intelligence data via HomePortfolio, aggregated for new builds in Islington. Data as of 11 July 2026.

What those figures mean for your cooling is the real story: the fabric is tight and efficient - a winter win, but precisely what bottles summer heat up indoors, and these are predominantly modern-build stock, tight enough that once heat gets in it has nowhere to go - which is why the overheating bites harder here than the weather alone suggests. On the environment: air quality (PM2.5) averages about 5.3 µg/m³ and daytime noise around 46 dB, in a borough that is a dense, inner-London borough that sits squarely inside the capital's urban heat island - which is what tells you if free night cooling is realistic. This is historic ground, too: a large share of these homes sit inside a conservation area and some sit close to a listed building - which is why the planning route for an outdoor unit needs more care here than the approval rate alone suggests. Being near a listed building is not the same as your home being listed.

What the data says about new builds in Islington

Start with what these homes are built from. Across Islington, new builds cluster at EPC band B - 61% of them sit there. That is an efficient rating on paper, yet it works against winter heat loss, not summer heat gain, so it barely touches the overheating problem. The full spread reads 61% at band B, 36% at band C, 3% at band D, so the picture is a range, not a single rating. 53% were built since 2000, so this is mostly lightweight, airtight modern construction - fabric that traps heat as effectively as it keeps it in.

Can you cool this home by opening a window at night?

It is worth testing whether you even need active cooling, or whether night ventilation would carry the load. At around 46 dB it is quiet enough that opening windows overnight is a genuine first line of defence, worth exhausting before you spend on active cooling. Local PM2.5 air quality, around 5.3 µg/m³, is not the limiting factor.

How the planning numbers look in Islington

For the planning side, conservation coverage is heavy for this stock: 234 of 415 new builds profiled in Islington fall inside one, about 56%, so assume the elevation matters. In conservation areas such as Barnsbury and Canonbury, expect the external siting to draw more scrutiny.

A worked cooling plan for a typical new build

Worked example · a typical new build in Islington

0out of 100Moderate overheating risk

Recommended system

Air-to-air heat pump

Cools in summer and heats in winter - the only cooling system the £2,500 grant can fund.

Replacing your direct-electric heating with an air-to-air heat pump cools in summer and heats in winter, and qualifies for the £2,500 Boiler Upgrade Scheme grant when installed by an MCS-certified installer.

Installer: MCS-certified

Boiler Upgrade Scheme

£0 grant - eligible

Eligible: replacing your direct-electric heating with an air-to-air heat pump via an MCS-certified installer qualifies for the £2,500 Boiler Upgrade Scheme grant.

Not claimable yet

The grant itself is law and your eligibility is real, but no air-to-air product has reached the MCS Product Directory yet, so no installer can issue a Boiler Upgrade Scheme voucher today. Air-to-air enters MCS scheme scope on 5 December 2026, and vouchers follow once certified products list. Get quotes now, but treat the grant as pending rather than banked.

  • Installed by an MCS-certified installer
  • Residential property only
  • Existing qualifying heating system is decommissioned, not retained alongside the new system
  • Not combined with another government heating grant for the same install
  • Air-to-air products must be listed on the MCS Product Directory before a voucher can be issued - not yet the case

Indicative cost

Typical install
£2,800–£3,220
Less grant
−£2,500
You pay
£300–£720
  • Indicative UK install cost, sourced from 2026 trade guides - actual quotes vary by property and installer.
  • Net cost shown after the £2,500 Boiler Upgrade Scheme grant.

Planning permission likely needed

  • The permitted-development right for a heat pump sits with the whole building, not the individual flat - you will usually need freeholder/management-company consent, and in practice that means a full planning application in most cases.
  • External condenser units must meet permitted-development noise limits regardless of planning route.
  • This is an indicative assessment only - always confirm the final position with your Local Planning Authority (LPA) before installing.
  • Listed-building status was not confirmed - if this building is also listed, listed-building consent will additionally be required.

Illustrative only. Your own floor, aspect, heating and conservation status change the result - check your specific address below.

The right system, and the £2,500 grant honestly

An outdoor air-source heat-pump condenser unit installed beside a home

For most Islington new builds, the strongest option is an air-to-air heat pump - a modern high-wall or ceiling unit, the same hardware people loosely call "air conditioning", except it heats as well as cools. It is near-silent, controllable room by room, and because it does both jobs it can replace your existing heating entirely. There are two honest ways this plays out, and which one applies to you turns on a single decision: whether you replace your heating or keep it. For context, a typical Islington new build runs around 63 sqm and already costs about £192 a year to heat - the baseline the figures below are measured against.

Branch 1 - replace your direct-electric heating, and the £2,500 grant is in play. The £2,500 air-to-air grant (Boiler Upgrade Scheme) only pays when the heat pump replaces your fossil-fuel or electric heating and is fitted by an MCS-certified installer. So if you take out your existing system and let the air-to-air heat pump handle your heating as well as your cooling, a job costing around £2,800-£3,220 installed can come down to roughly £300-£720 net. Eligibility is per-property and depends on your current heating and the installer's accreditation - our checker confirms it against your address. (Grant rules as of August 2026 and subject to change.)

Branch 2 - keep your boiler and simply add cooling, and the grant does not apply. If you want to keep your existing heating and only add cooling, that is a private-pay job - a cooling-only add-on that keeps your boiler is not eligible for the £2,500 grant, whatever your heating type. The sensible choice here is usually a single-split air conditioning unit (around £1,500-£3,000 installed), carried out by an F-Gas / REFCOM-registered engineer - not MCS, which applies only to the grant-eligible heat-pump route above.

We match you to the right accreditation for whichever path fits your home: MCS for the grant-eligible heat pump, F-Gas / REFCOM for a pure cooling install. For a typical new build in Islington at around 63 sqm, sized to that footprint, our checker leans toward air-to-air heat pump, but your own floor, aspect and heating decision move the answer - which is the whole point of checking your specific address.

What cooling costs in Islington in 2026

Air-to-air heat pump versus single-split air conditioning: cost, grant eligibility and installer accreditation, for a 2-room home.
Air-to-air heat pumpSingle-split AC
What it doesCools in summer and heats in winterCools only
Typical install cost£2,800 - £3,220£1,500 - £3,000
The £2,500 grantIf you replace fossil-fuel or electric heating, via an MCS installerNot eligible
Cost after grant£300 - £720 (if eligible)£1,500 - £3,000
Installer accreditationMCSF-Gas / REFCOM
Indicative UK install costs for a 2-room home, from 2026 trade-guide bands - actual quotes vary by property and installer. The grant applies only when an air-to-air heat pump replaces qualifying heating.

Planning permission in Islington

Planning is the step flats most often get wrong, and it matters more than usual in Islington: with conservation areas covering a large share of the borough, a house's usual permitted-development route frequently does not apply, and a street-facing unit generally needs consent from the London Borough of Islington. In Islington, conservation areas such as Barnsbury, Canonbury and Clerkenwell are where this bites hardest. One recent rule change matters here. As of May 2025 an air-to-air heat pump counts as a heat pump for planning, so a house can often install one under permitted development within the size and siting limits - whereas a pure cooling unit, which only cools, still needs a full planning application. Which system fits your home therefore decides which planning route you are on. For a typical new build here, our checker's read is: planning permission is likely required. External condenser units must meet permitted-development noise limits regardless of planning route. This is an indicative assessment only - always confirm the final position with your Local Planning Authority (LPA) before installing. Listed-building status was not confirmed - if this building is also listed, listed-building consent will additionally be required. Islington guidance steers external units to rear or courtyard elevations, away from the street, which is often the difference between a straightforward application and a refusal. It is very doable - the London Borough of Islington approves plenty of these - but it is a step, not a formality, and it is exactly the kind of thing worth checking against your specific address before you commit. Treat this as indicative guidance, not legal advice.

56%

of new builds in Islington sit inside a conservation area

2%

within 30 metres of a listed building

Conservation-area and listed-building status both tighten the planning route for an outdoor unit. Sitting near a listed building does not by itself make a home listed, so the checker confirms your property individually.

Conservation-area and listed-building records © Historic England 2026, via planning.data.gov.uk, used under the Open Government Licence v3.0. Data as of July 2026. See all data sources.

Permitted development, or a planning application?

An outdoor air-source heat-pump / air-conditioning condenser unit mounted beside a home

Air-to-air heat pump (heats and cools)

Can be permitted development

Can be permitted development on a house under Class G, within size, siting and noise limits, because since 29 May 2025 a unit that also heats is no longer excluded for cooling.

Pure air conditioning (cooling only)

Needs planning permission

Not permitted development - a cooling-only condenser fails the Class G "not solely for cooling" condition and there is no other PD class for it, so it needs a full planning application.

England permitted-development conditions for an outdoor unit: air-to-air heat pump versus cooling-only air conditioning.
Air-to-air heat pumpCooling-only AC
Does the permitted-development route apply?Yes on a house, within the Class G limits below (it heats as well as cools).No - a cooling-only unit needs full planning permission.
Property typeHouses get the Class G right directly. For a flat the right sits with the whole building (one unit for the block) and needs freeholder consent, so in practice a flat almost always needs permission.Planning permission required either way.
Maximum outdoor-unit sizeUp to 1.5 cubic metres on a house (0.6 cubic metres for a block of flats).Not applicable - planning permission required.
Number of unitsUp to two on a detached house; otherwise one.Not applicable - planning permission required.
Where it can goNot on a pitched roof; on a flat roof it must sit at least 1 metre from the edge; not on a wall above ground-floor level that faces a highway.Set by the planning application.
Conservation areaStricter - it must not go on any wall or roof that faces a highway, and an Article 4 direction can remove the right entirely.Planning permission required.
Listed buildingExcluded from permitted development; listed-building consent is needed regardless.Excluded from permitted development; listed-building consent is needed regardless.
NoiseMust pass the MCS Planning Standards (MCS 020) sound test, measured at the nearest neighbour's door or window.Any planning permission will set its own noise conditions.

England only, as of 29 May 2025 (reflects the 29 May 2025 Class G change, SI 2025/560). Sources: GPDO 2015, Schedule 2, Part 14, Class G (air source heat pumps); SI 2025/560 (the 2025 amendment).

This is an indicative summary of England permitted-development rules for outdoor units, not legal advice. Rules change and vary locally - confirm the final position with your Local Planning Authority before installing.

Common questions about cooling a new build

Does a top-floor or new build in Islington really overheat?

Comfortably, yes. We put a typical Islington new build near 53 out of 100 on our overheating scale ("moderate"). Islington holds around 415 homes of this type - 0.3% of the borough's certified stock - and roof heat gain, thin thermal mass in older stock and the local heat-island effect combine to leave homes like this uncomfortable from late June, whatever the thermostat suggests.

What is the best cooling system for a new build in Islington?

For a Islington new build, an air-to-air heat pump is generally the strongest pick - a quiet, room-by-room unit that both cools in summer and heats in winter. If you would rather leave your boiler in place and only add cooling, the usual private-pay option is a single-split air conditioning unit. Our checker points to air-to-air heat pump for a typical home here, but your own floor, aspect and heating choice can move it - so it pays to check your address. These new builds average around 63 sqm. A typical Islington new build already costs around £192 a year to heat.

Can I get the £2,500 grant for cooling my Islington home?

Only in one specific case, and it is worth being precise. You are eligible for the £2,500 air-to-air grant (Boiler Upgrade Scheme) only when an air-to-air 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. Eligibility is per-property, so our checker confirms it against your address. (Grant rules as of August 2026 and subject to change.) Given a typical Islington new build already costs around £192 a year to heat, replacing that heating as part of this route is usually where most of the saving comes from.

Do I need planning permission for air conditioning in Islington?

Often, yes - more often than for a house. Permitted-development rights that let a house fit an outdoor unit do not apply the same way to flats, and much of Islington sits inside a conservation area, especially around Barnsbury, where an external condenser on a front or side elevation usually needs council permission. It is very doable, but treat it as a step to plan for, not a formality - our checker gives you the likely position for your specific address.

How much does it cost to cool a new build?

Using 2026 UK trade prices as a guide: an air-to-air heat pump for a home like this runs around £2,800-£3,220 installed, dropping to roughly £300-£720 net where it replaces your heating and qualifies for the grant. Keeping your boiler and adding a single-split air conditioning unit instead is about £1,500-£3,000 installed with no grant. Real quotes move with access, unit size and pipe runs. A typical Islington new build currently costs around £192 a year to heat. That heating bill sits alongside the cooling cost above, not instead of it.

MCS or F-Gas - which installer do I actually need?

It depends on the route, and getting it wrong is a common trap. The grant-eligible air-to-air heat pump route needs an MCS-certified installer - that accreditation is what the grant requires. A pure cooling install (a single-split, multi-split, ducted or portable unit that keeps your existing heating) needs an F-Gas / REFCOM-registered engineer, not MCS. We match you to the right accreditation for whichever path fits your home. This is a separate question from planning permission - the London Borough of Islington handles that side, and accreditation is ours to get right.

If I use the checker, will you cold-call me?

No. The free cooling check shows your full plan on screen straightaway, with no phone call and no waiting. If you would like us to email your plan, or to have a single vetted local installer contact you about a survey, you choose that at the end - we only get in touch if you ask, and you are never sold to five companies at once.

Is air conditioning banned in new-build homes?

No - there is no ban on cooling a new-build. The confusion comes from Building Regulations Part O, which requires new homes to limit overheating by design, and from management-company or lease rules that control external units. None of that bans air conditioning; it just means you may need permission for an outdoor condenser. The checker shows where you stand for your Islington address.

What is Part O and does my new-build flat need to comply?

Part O is the Building Regulations standard that limits overheating in new homes, assessed with the CIBSE TM59 method. It applies to the design and construction of new dwellings, so compliance is the developer's job, not something you retrofit. If your new-build still overheats in practice - as many airtight flats do - active cooling is a separate, unregulated choice you are free to make.

Do I need my management company's permission to fit air conditioning in a new-build flat?

Very often, yes. New-build flats usually come with a lease and a managing agent whose consent is required for external alterations, including an outdoor condenser. Ask for the process in writing early, since it can take time, and treat it as separate from any planning permission. The checker covers the planning side for your address.

What size outdoor unit can I fit under permitted development?

It depends on the system. Since 29 May 2025 (SI 2025/560), an air-to-air heat pump - which heats as well as cools - can be permitted development on a house: broadly a unit no larger than 1.5 cubic metres (0.6 cubic metres for a block of flats), and not on a wall above ground-floor level facing a highway, as long as you are not in a conservation area. A pure, cooling-only air conditioning unit does not get that route - it needs a full planning application whatever its size. Flats and conservation areas usually fall outside the permitted-development rights either way, so a unit there typically needs permission. The checker applies this to your address. In Islington, that conservation-area exclusion bites hardest around places like Barnsbury.

Does the air-to-air grant still apply if I add air conditioning but keep my gas boiler?

No. You are eligible for the £2,500 air-to-air grant (Boiler Upgrade Scheme) only when an air-to-air 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 cooling-only add-on is not eligible for the £2,500 grant, whatever your heating type - it is an F-Gas / REFCOM job instead. (Grant rules as of August 2026 and subject to change.) Given a typical Islington new build already costs around £192 a year to heat, that saving is only available on the replace-your-heating route above.

Check your own Islington home

Pre-scoped to a new build - enter your address for a plan specific to your property.

  1. Address
  2. Confirm
  3. Questions
  4. Plan

Let's look at your home

We use property data to pre-fill the boring bits - no long forms, and we never cold-call you.

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 my Islington home

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.

Every figure above - overheating scores, costs, grant rules and planning positions - follows our published methodology.

Related cooling guides

The grant and planning in Islington

Learn more about cooling a UK home