Do I need freeholder permission to replace windows in a flat?

Almost always, because the windows usually form part of the structure the freeholder owns. Check the lease and get consent in writing before ordering.

Who pays for new windows in a leasehold flat?

It depends on the lease. Some make the freeholder responsible and recover it through the service charge, others put it on the leaseholder. The lease is the only answer.

Can I choose any style for a flat?

Usually not. Blocks are normally required to keep a consistent appearance, so the style, colour and opening arrangement may be fixed by the freeholder or the managing agent.

Costs by property

Cost of new windows for a flat

A flat typically needs four to six windows, roughly £2,000 to £4,250 in uPVC supplied and fitted for five. The cost is rarely the difficult part: leasehold consent, the freeholder, building access and the fact that flats do not have the permitted development rights houses do are what usually hold the job up.

This is the property type where the paperwork is harder than the work, and where people most often discover halfway through that the decision was not theirs alone.

Worked example

5 windows

uPVC: £2,000 – £4,250
aluminium: £3,000 – £6,250
timber: £4,000 – £8,000

£2,000 – £4,250

supplied and fitted, uPVC

These figures come from published industry price guides, not official statistics, and several of those sources are installers or comparison sites with a commercial interest. They are a starting point for a conversation, not a quote. Your installer sets the actual price after measuring.

Costwise UK new windows cost guide · checked 2026-10-09
Checkatrade double glazing cost guide · checked 2026-10-09

The windows may not be yours

In most leases the external windows are part of the structure, and the structure belongs to the freeholder. Your lease may make them responsible for maintaining them, you responsible, or it may be silent and therefore arguable.

Read the lease before you get quotes. If the freeholder is responsible, you may be able to require the work rather than pay for it, and if you are responsible you will almost certainly need their written consent to alter the appearance.

Permitted development does not apply

The permitted development rights that let a householder replace windows without planning permission apply to houses. They do not apply to flats and maisonettes.

In practice a like-for-like replacement is often accepted, but the legal position is that you should check with the local planning authority rather than assume. In a conservation area, assume you need to ask.

Access, and tilt and turn

Above the ground floor, an outward-opening casement is awkward to clean and can be a hazard over a walkway or balcony. This is why managing agents frequently specify tilt and turn windows for apartment blocks: the sash comes inwards so both faces can be cleaned from inside.

If there is no external access at all, inward-opening is not a preference but a requirement, and it should be settled before anything is ordered.

Questions

Do I need freeholder permission to replace windows in a flat?: Almost always, because the windows usually form part of the structure the freeholder owns. Check the lease and get consent in writing before ordering.
Who pays for new windows in a leasehold flat?: It depends on the lease. Some make the freeholder responsible and recover it through the service charge, others put it on the leaseholder. The lease is the only answer.
Can I choose any style for a flat?: Usually not. Blocks are normally required to keep a consistent appearance, so the style, colour and opening arrangement may be fixed by the freeholder or the managing agent.