Why Terraced Houses Can Finally Get Air Conditioning (2026 Planning Update)

Last Updated: November 2025

If you live in a terraced or semi-detached house in the UK, you have probably been told “No” by air conditioning companies before.

For years, strict planning rules meant installing a heat pump or AC unit in a standard terraced garden was legally impossible without a long, expensive planning application. But thanks to a quiet change in the law earlier this year, that barrier has effectively vanished.

Can I install a heat pump in a terraced house? Yes. As of May 2025, the “1-metre boundary rule” for Permitted Development has been removed in England. This means you can now install an air-to-air heat pump (air conditioning) in a terraced property without full planning permission, provided the unit is MCS certified and meets noise standards.

The “1-Metre Rule” Explained (And Why It’s Gone)

Previously, Permitted Development rights (Class G) stated that any air source heat pump had to be at least 1 metre away from the property boundary.

In a typical UK terraced house with a side return or a small back garden, this was impossible. If you put a unit 1 metre from your fence, it would likely be in the middle of your patio.

The New Rule: The government has scrapped the 1-metre restriction to encourage heat pump uptake. You can now install a unit closer to the boundary, provided it meets the standard noise calculations (which our MCS-certified units do).

“This rule change is huge for the UK housing market. It effectively unlocks millions of terraced homes that were previously ‘unsuitable’ for green heating. We can now fit slimline units in side returns and small courtyards where we simply couldn’t go before.”

— Rhys Powell, F-Gas Engineer at WarmZilla

Does this mean I get the £2,500 Grant too?

Yes. The £2,500 Boiler Upgrade Scheme (BUS) grant applies to Air-to-Air Heat Pumps regardless of whether you live in a detached mansion or a mid-terrace.

By combining the new planning freedom with the £2,500 grant, this is the perfect time to upgrade a terraced home.

Cost Breakdown for a Terraced House

But what about the noise? (The “Neighbour Factor”)

In a terraced street, your neighbours are close. This is why people worry about AC.

However, to qualify for the grant (and Permitted Development), the unit must be MCS Certified. Part of this certification involves a noise assessment.

Modern units run at around >42dB – 46dB. To put that in perspective:

• 30dB: A whisper
• 40dB: A quiet library
• 50dB: A refrigerator humming
• 60dB: Normal conversation

Your new heat pump will likely be quieter than the traffic on the road outside your house.

Where can we install it?

With the new rules, we have flexible options for terraced properties:

• The Backyard Wall: The most common spot.
• The Side Return: Now possible thanks to the rule change.
• Flat Roofs: Possible, but requires a specific 1-metre clearance from the roof edge (this rule remains).

Check Your Eligibility

If you own a terraced house, have a valid EPC, and want cooling for next summer, you are likely eligible.

Frequently Asked Questions

Do I need to tell my neighbours?

You don’t legally need their permission if it falls under Permitted Development, but we always recommend a friendly chat. We can provide a spec sheet showing the low noise levels to reassure them.

Will it replace my gas boiler?

No. In a terraced house, we recommend keeping your gas boiler for hot water and radiator heating on the coldest days. The Air-to-Air unit acts as your primary heat source for the main living areas (and your only cooling source in summer).

What if I live in a Conservation Area?

The rules are stricter here. You can usually still install one, but the outdoor unit generally shouldn’t be visible from the road (highway). Our surveyors can advise on discreet placement.