Medway · cooling guide
How to cool a new build in Medway
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 Medway 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.
Just 1% of Medway's EPC-certified stock is new build, but those 1,582 modern homes overheat in their own way: lightweight post-2000 construction with lower thermal mass warms rapidly on sunny afternoons. Many are also on direct-electric heating already, which affects which cooling system makes the most sense.
If your Medway new build gets uncomfortably hot the moment summer arrives, you are not the only one - and although new builds are a smaller share of the borough (about 1,582 homes, 1.2%), they overheat about as reliably as any home type here. On our overheating scale a typical Medway new build lands near 48 out of 100 - "moderate" - meaning the fan-and-open-window routine stops coping once real heat arrives. Here is the property-specific answer: the right cooling system for your home, what it realistically costs, and whether you need planning permission - before you speak to a single installer.
Why new builds in Medway 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 Medway new build, the median floor area is around 97 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 Medway: by the numbers
1% of Medway homes are new builds
1,582 of 127,777
97 m²
median floor area
£265
median annual heating cost
EPC band distribution
1,582 new builds in Medway with an EPC on record
Greener bands are more energy-efficient; red bands (E-G) are poorer-fabric homes that trap summer heat.
| EPC band | Homes | Share |
|---|---|---|
| A | 17 | 1% |
| B | 1,435 | 91% |
| C | 109 | 7% |
| D | 21 | 1% |
| E | 0 | 0% |
| F | 0 | 0% |
| G | 0 | 0% |
When these homes were built
Construction era of 1,472 new builds in Medway
- pre-1919 0%
- 1919-1944 0%
- 1945-1999 8%
- 2000+ 92%
| Era | Homes | Share |
|---|---|---|
| pre-1919 | 0 | 0% |
| 1919-1944 | 6 | 0% |
| 1945-1999 | 112 | 8% |
| 2000+ | 1,354 | 92% |
Real EPC and property-intelligence data via HomePortfolio, aggregated for new builds in Medway. Data as of 11 July 2026.
What those figures mean for your cooling is the real story: the fabric here is efficient, which trims winter bills but is exactly what seals summer heat inside, and these are mostly modern, airtight construction that holds onto whatever heat gets in - which is why the overheating bites harder here than the weather alone suggests. Set against that, Medway is a town that warms markedly in prolonged hot spells, though its evenings cool faster than a big-city core, and air quality (PM2.5) averages about 4.8 µg/m³ and daytime noise around 43 dB - together these decide whether night ventilation is a real option here. This is historic ground, too: a small 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 Medway
The fabric itself decides a lot before any system is fitted. Across Medway, new builds cluster at EPC band B - 91% 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 91% at band B, 7% at band C, 1% at band A, so the picture is a range, not a single rating. 92% 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 43 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 4.8 µg/m³, is not the limiting factor.
How the planning numbers look in Medway
For the planning side, conservation coverage is light for this stock: 19 of 1582 new builds profiled in Medway, about 1%, leaving most of them clear of it. In conservation areas such as Halling and Brompton Lines, expect the external siting to draw more scrutiny.
A worked cooling plan for a typical new build
Worked example · a typical new build in Medway
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.
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
For most Medway 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 Medway new build runs around 97 sqm and already costs about £265 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 Medway at around 97 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 Medway in 2026
| Air-to-air heat pump | Single-split AC | |
|---|---|---|
| What it does | Cools in summer and heats in winter | Cools only |
| Typical install cost | £2,800 - £3,220 | £1,500 - £3,000 |
| The £2,500 grant | If you replace fossil-fuel or electric heating, via an MCS installer | Not eligible |
| Cost after grant | £300 - £720 (if eligible) | £1,500 - £3,000 |
| Installer accreditation | MCS | F-Gas / REFCOM |
Planning permission in Medway
Medway's genuinely low conservation-area coverage works in your favour on planning. A house fitting an outdoor condenser usually clears permitted development without extra paperwork, though flats do not get the same automatic route and typically still need Medway Council's permission for a front or side unit. In Medway, conservation areas such as Halling, Brompton Lines and New Road, Rochester are where this bites hardest. Worth flagging a 2025 change: because an air-to-air heat pump heats as well as cools, a house can now often fit one under permitted development within set limits, while a cooling-only air conditioner cannot and needs planning permission outright. So your choice of system, not just the property itself, moves the planning answer. 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. Medway carries genuinely low conservation-area coverage (about 5% of EPC-certified homes), which makes an external unit a lower-friction proposition here than in a heritage-dense borough for most addresses - a real advantage, not a workaround. None of this is a dealbreaker - approvals happen for homes like this all the time - but it is a step to plan for rather than a given, and one worth confirming for your specific address before you commit. This is indicative guidance, not legal advice.
1%
of new builds in Medway sit inside a conservation area
0%
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?
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.
| Air-to-air heat pump | Cooling-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 type | Houses 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 size | Up to 1.5 cubic metres on a house (0.6 cubic metres for a block of flats). | Not applicable - planning permission required. |
| Number of units | Up to two on a detached house; otherwise one. | Not applicable - planning permission required. |
| Where it can go | Not 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 area | Stricter - 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 building | Excluded from permitted development; listed-building consent is needed regardless. | Excluded from permitted development; listed-building consent is needed regardless. |
| Noise | Must 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 Medway really overheat?
Yes - measurably. Our overheating model scores a typical Medway new build around 48 out of 100 ("moderate"). Medway holds around 1,582 homes of this type - 1.2% of the borough's certified stock - and the combination of roof heat gain, low thermal mass in older stock and the local heat-island effect means many of these homes are uncomfortable from late June onward, whatever the thermostat says.
What is the best cooling system for a new build in Medway?
For most Medway new builds the strongest option is an air-to-air heat pump, which cools in summer and heats in winter from the same near-silent, room-by-room unit. If you would rather keep your existing boiler and only add cooling, a single-split air conditioning unit is the usual private-pay choice. Our checker leans toward air-to-air heat pump for a typical home of this type, but your floor, aspect and heating decision move the answer - which is why it is worth checking your own address. These new builds average around 97 sqm. A typical Medway new build already costs around £265 a year to heat.
Can I get the £2,500 grant for cooling my Medway 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 Medway new build already costs around £265 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 Medway?
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 Medway sits inside a conservation area, especially around Halling, 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?
As an indicative guide sourced from 2026 UK trade prices: an air-to-air heat pump for this home is around £2,800-£3,220 installed, coming down to roughly £300-£720 net if it replaces your heating and qualifies for the grant. A single-split air conditioning unit that keeps your boiler is around £1,500-£3,000 installed with no grant. Actual quotes vary with access, unit size and pipe runs. A typical Medway new build currently costs around £265 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 - Medway Council 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, cooling a new-build is not banned. The mix-up comes from Building Regs Part O (which makes new homes limit overheating by design) and from lease or managing-agent rules on external units. Neither outlaws air conditioning; they just mean an outdoor condenser may need permission. The checker shows where you stand for your Medway address.
What is Part O and does my new-build flat need to comply?
Part O is the Building Regs standard limiting overheating in new homes, judged by the CIBSE TM59 method. It governs how new dwellings are designed and built, so it is the developer's responsibility, not a retrofit. If your new-build overheats anyway - common in airtight flats - active cooling is a separate, unregulated option open to you.
Do I need my management company's permission to fit air conditioning in a new-build flat?
Frequently, yes. A new-build flat usually has a lease and a managing agent whose permission is needed for external changes such as a condenser. Request the process in writing early - it takes time - and keep it distinct from planning permission. The checker handles 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 Medway, that conservation-area exclusion bites hardest around places like Halling.
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 Medway new build already costs around £265 a year to heat, that saving is only available on the replace-your-heating route above.
Check your own Medway home
Pre-scoped to a new build - enter your address for a plan specific to your property.
- Address
- Confirm
- Questions
- 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 Medway homeYou 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.
