Home air conditioning in Dartford
Which room of your Dartford home do you give up on by July? We fit domestic air conditioning in new-build flats, 1930s semis, terraces and detached houses, and most jobs begin with a bedroom, a loft room or a top-floor flat that holds the day's heat into the night. The room settles at the temperature you set, and the same unit heats it from October.
Price a home system
Three details and we call you back with the next step.
- Models picked for sleeping beside
- Winter heating from the same wall unit
- We tell you when a blind would do
Why do the newest homes in Dartford run hottest?
Because they were never asked not to. Dartford's population climbed 20.0% between the 2011 and 2021 censuses, a rise beaten by only one other council in England, and the homes that absorbed it are mostly flats and close-set houses with big windows and no draught from front to back. The Building Regulations did not require an overheating assessment for new homes until 15 June 2022, and converted buildings still escape the rule. Older housing has its own trouble spots: among the borough's 45,696 households, 14,398 are in semis and 14,103 in terraces, where the rear bedroom under the afternoon sun, or a loft conversion, is the room that bakes. UCL researchers publishing in 2019 found converted lofts carry a far greater overheating risk than ordinary bedrooms. Sources: ONS; Planning Portal; Elmhurst Energy; Census 2021; Li, Taylor and Symonds.
What do the nights do here?
They stay warm longer than the averages suggest. Greenwich Observatory, the Met Office station nearest Dartford, records a mean July night-time low of 13.9°C and 14.1°C in August, but a thirty-year mean smooths out exactly the nights that matter: during a heatwave along the Thames the thermometer sits far higher, and on 10 August 2003 Gravesend-Broadness, a few miles downriver, hit 38.1°C in the afternoon. Government research treats 26°C as the point past which a bedroom stops delivering proper sleep. That is why the bedroom is the first room people ask us about. Sources: Met Office; KentOnline; MHCLG.
Can you sleep next to one?
Comfortably. The part that makes the noise, the compressor, lives outside. What is in the bedroom is a fan and a coil, and at its lowest speed a good wall unit is quieter than the fridge downstairs; when you compare models, ask for the sound figure at minimum fan speed rather than the headline number. There is a second noise test, for the neighbours: to qualify as permitted development the calculated sound at their nearest door or window must not exceed 37 dB(A). Source: Grant UK.
Is there anything cheaper worth trying first?
Shade and night air, where you can use them. In the UCL loft study, external shutters reduced overheating by 96% and opening windows at night by 89%, with night ventilation judged the best value of all the measures. The difficulty is the phrase "where you can use them": the same government research found more than half of households sometimes report barriers to opening their windows, chiefly noise and security, and a home beside the A2, the A282 or one of Dartford's railway lines meets both. Air conditioning is for the rooms where the free remedies have failed. Sources: Li, Taylor and Symonds; MHCLG.
Who else has to say yes?
Whoever owns the outside of the building. In 2021, 18.1% of Dartford households rented privately, against 15.9% a decade before, and a tenant must have the landlord's permission in writing before anything is fixed to the fabric. A leaseholder needs the freeholder's consent, normally through a licence to alter. On the newer estates a management company may hold covenants over the outside of the house as a third party. When that permission is slow or refused, the practical alternatives are a unit with no outdoor box or a portable, and the flats guide walks through each case. The housing figures behind this are on our air conditioning in Dartford page. Sources: ONS; LEASE.
Questions people ask
How big a unit does a bedroom take?
iHeat's starting figures are 1.5 to 2.0kW for 10 to 15 square metres and 2.0 to 2.5kW up to 25, with more for large or south-facing windows and for loft rooms. The size guide covers the adjustments.
Will it make the room dry?
Cooling pulls moisture from the air, which is why the indoor unit has a drain, and in a stuffy flat that is mostly a relief. If anyone in the house has asthma or allergies, say so and we choose a model with better filtration.
Could one indoor unit cool two bedrooms?
Not with a door between them: cooled air does not travel through walls. Each closed room wants its own indoor unit, which is what a multi-split provides.
Sources we checked
- ONS: how the population changed in Dartford, Census 2021
- Planning Portal: Approved Document O, overheating in new homes
- Elmhurst Energy: Part O leaves conversions and extensions out (June 2025)
- Census 2021: accommodation type, Dartford
- Li, Taylor and Symonds: overheating and mitigation in converted lofts in London (2019)
- Met Office: climate averages for Greenwich Observatory, 1991 to 2020
- KentOnline: the day Gravesend was the hottest place in Britain (2022)
- MHCLG: research into overheating in new homes, phase 1 (2019)
- Grant UK: planning guide for heat pumps in England, with the 37 dB(A) test (May 2025)
- ONS: how life has changed in Dartford, Census 2021
- LEASE: whether a leaseholder needs the landlord's permission to alter a flat
- iHeat: what size of air conditioner a room needs (May 2026)
Worth knowing before you ring
With these we can usually tell you on the first call whether the job is simple.
- The postcode
- Whether it is a house, a flat or business premises, and roughly its age
- If you rent or lease, who owns the external wall
- Which room, how big, and the direction its window faces
- Any management company, conservation area or listing that applies
Home air conditioning outside Dartford
Looking for home air conditioning in one of the towns around us? Each page below sets out that place's own housing and planning position, and our air conditioning in Dartford page gives the full picture.
Worth reading first
Bedroom air conditioning: what it does for sleep, and what it costs
The sleep threshold, noise at night, sizing and the price of a quiet bedroom.
Air conditioning in a flat: who has to agree, and in what order
Lease, freeholder, management company and planning, in the order to tackle them.
Cooling a loft conversion: the options that work
Why lofts cook, the free fixes first, then where a unit goes on a dormer.
Jobs that often go with this one
Air conditioning installation
The whole job from the first measurement to the handover of the remote, with every consent checked on the way.
Air-to-air heat pumps
The same wall unit, run the other way: a room heated for pence an hour, with the summer cooling thrown in.
Multi-split air conditioning
Several rooms, one box in the garden. The design that fits inside a semi's single permitted outdoor unit.
Conservatory air conditioning
For the glass room that is a greenhouse in July and a fridge in January, and the garden office beside it.
The rest of what we do
Office air conditioning
Offices from a room above a shop to a floor on a business park, with the heat rules and the landlord dealt with.
Commercial air conditioning
Retail and hospitality premises, sized with the door open and the bedroom over the shop remembered.
Server room cooling
Dedicated cooling for the rack, calculated from the wattage on the plugs and running when the office is dark.
Air conditioning servicing
An annual visit for any system by any installer, with the legal leak check where the charge demands one.
Air conditioning repairs
Warm air, a puddle under the indoor unit, ice on the pipes or a blinking code: the cause found before anything is ordered.
Want us to ring you?
A name, a number and a postcode is enough. Say which room if you can. Or ring 01322 952910.