Air conditioning installation in Ilford

What does fitting a split system involve?

Two units and the services that join them. Inside, a slim head is fixed high on one wall of the room. Outside, the unit holding the compressor and fan sits on a wall bracket or on pads at ground level. Linking them are two insulated copper refrigerant lines, a power and signal cable, and a narrow drain that takes away the moisture condensed on the indoor coil. On a two-storey terrace with a back addition, a rear bedroom can usually be served through one cored hole, with the outdoor unit on a bracket over the side return. A front bedroom, a flat on an upper floor or a room with no outside wall takes more planning: the lines may travel through the loft, along a ceiling void or down the face of the building inside a cover.

What do we look at on the survey?

Anything that could change the price or stop the job, before a figure is written down.

• The room. Floor area, ceiling height and the direction the windows face set the capacity. The sizing guide gives the starting figures.
• The outside wall. Who owns it: you, a landlord, a freeholder or a management company.
• The outdoor position. Where the unit can stand, and the sound level it would give at the nearest window or door next door.
• The drain. Whether the water can fall naturally to a gully or needs a small pump.
• The consumer unit. Whether it has room for a new circuit.
• Access. Ladders, a tower or nothing special, which matters on upper floors.

If the building rules a fixed unit out, you hear it at the survey, before you commit to the job.

Does an air conditioning installation in Ilford need planning permission?

On most houses it does not, as long as the unit meets every permitted development condition written for heat pumps. Since 29 May 2025 those rules exclude a unit run purely for cooling, so it has to be a reversible model that you also use to heat. A semi or terrace may have one outdoor unit and a detached house two; on a house the unit must not exceed 1.5 cubic metres or go on a pitched roof, and the sound calculated for the closest neighbouring door or window can be no more than 37 dB(A). Flats are tighter. A whole block gets one unit no larger than 0.6 cubic metres, and a building with a shop on the ground floor does not count as a block of flats at all. Redbridge has 16 conservation areas, where street-facing walls and roof slopes are off limits, and a listed building has no permitted development right. Neighbouring boroughs add their own guidance: Waltham Forest's, adopted on 11 June 2026, prefers mechanical ventilation with heat recovery to air conditioning, and Hackney's September 2025 draft called residential units "typically not acceptable" (the guidance was adopted in December 2025, so check the adopted wording) (more on our Walthamstow and Hackney pages). The planning guide covers each case. Sources: SI 2025/560; Planning Portal; Grant UK; Redbridge Council; Waltham Forest Council; Hackney Council draft.

Why does the electrical supply need certifying?

Wiring a new circuit into a home counts as notifiable work under Part P, the electrical section of the Building Regulations. Most splits need their own supply from the consumer unit, with a switched fused connection inside and a weatherproof isolating switch next to the outdoor unit. The electrician either belongs to one of the five government-approved competent person schemes, and self-certifies the work, or has it signed off by a registered third-party certifier, a role that NAPIT alone is currently authorised to carry out. Through a scheme, the certificate should reach you within eight weeks of the work being finished. Checkatrade's national figure for this part of the job is £400 to £700. Whoever does the work, ask which scheme the electrician is registered with. Sources: IET; GOV.UK; Checkatrade.

Who may connect and fill the refrigerant circuit?

Only a technician with the matching F-gas qualification. A Category 1 holder may do any of the work; Category 2 allows installing and servicing systems that hold less than 3kg of refrigerant, which takes in ordinary domestic splits. A business doing this work on equipment belonging to others must also hold company certification from one of the approved bodies, and that certificate lapses after three years unless renewed. For air conditioning and heat pumps those bodies are Refcom, F-Gas Register (Quidos) and Bureau Veritas. Before the refrigerant is released, the joined pipework is pressure-tested and then evacuated to draw out air and moisture. Ask any installer for the technician's qualification and the firm's certificate number, and check both as our F-gas guide describes. Sources: GOV.UK, F-gas qualifications; GOV.UK, company certification.

What does a single-room installation cost?

We price each job after the survey, so the only figures here are national ones. Checkatrade's May 2026 guide puts a 12,000 BTU wall-mounted unit at £750 and the labour to fit it at £1,150. Added together, which is our sum and not theirs, that comes to about £1,900, before the £400 to £700 it gives for the electrics. Four things move a real quote: how much output the room calls for, how long and awkward the pipe run is, how high the outdoor unit goes and how we reach it, and any fees for consent. In a tower, such as the buildings of up to 36 storeys approved at Chapel Place, there may be no outdoor position the freeholder will accept, and a through-wall unit with nothing hung outside becomes the option to look at. The cost guide works through the extras, and air conditioning across Ilford explains how local buildings change the job. Sources: Checkatrade; Construction Enquirer.