Licence to alter — the consent nobody tells flat owners about

Here is the mistake we see most often in London renovations: a leaseholder gets planning permission (or correctly establishes none is needed), hires a builder, starts work — and receives a solicitor's letter from the freeholder. The project stops. Because for a leasehold flat, the council was never the only gatekeeper. Your lease is a contract, and almost every London lease requires the freeholder's written consent — a licence to alter — before structural or significant alterations.

This is not a planning consent. It is private law, it runs in parallel with planning, and it catches people precisely because no council, portal or builder is obliged to mention it. Most of London's flats — the majority of homes in inner boroughs like Westminster, Kensington & Chelsea, Camden and Islington — sit under leases with alteration covenants. If you own a leasehold flat and you're planning works, read this before you book a builder.

What a licence to alter is

A licence to alter (also called a licence for alterations) is a formal legal document in which your freeholder — or the management company holding the relevant covenants — consents to specified works, on conditions. It typically sits as a deed alongside your lease, and it follows the flat: when you sell, your buyer's solicitor will ask for it.

What requires consent depends entirely on your lease wording, but the covenants come in three flavours:

• Absolute covenant — "the leaseholder shall not make alterations." The freeholder can simply refuse (though in practice many will negotiate).
• Qualified covenant — alterations only with the landlord's consent. For improvements, statute steps in: section 19(2) of the Landlord and Tenant Act 1927 implies that consent cannot be unreasonably withheld.
• Fully qualified covenant — the lease itself says consent will not be unreasonably withheld.

Typical works that need a licence: removing or altering any wall (structural or not, depending on the lease), relocating kitchens or bathrooms, altering services that pass through the building, changing floor finishes or build-ups (acoustic covenants are common — the carpet clause is real), new openings, anything touching the structure, windows, or external fabric, and combining flats. Many leases catch far more than owners expect — some require consent even for non-structural reconfiguration.

Usually fine without: decoration, like-for-like kitchen or bathroom replacement in the same location, and minor works that don't touch structure, services, or demised boundaries — subject to your lease's actual wording, which is the only authority on the question.

Licence to alter vs planning permission — both, either, or neither

The process, and who pays

• Read the lease first. The alterations covenant, the demise (what you actually own — often not the structure), and any specific clauses on flooring, services and windows. This defines everything that follows.
• Notify the freeholder or managing agent with a description of proposed works — for anything structural, that means drawings and a structural engineer's details, not a paragraph of text.
• The freeholder appoints a surveyor (and usually a solicitor) to review. The part that surprises leaseholders: you pay their fees as well as your own — the lease almost always entitles the freeholder to recover the reasonable costs of considering the application and drafting the licence.
• Conditions are negotiated — working hours, protection of common parts, acoustic specifications for floors, reinstatement obligations, insurance requirements, sometimes a deposit.
• The licence is executed as a deed — only then should works begin.
• On completion, some licences require sign-off that works were done as consented.

Costs run higher for complex schemes, prime-central buildings, or institutional freeholders. The single biggest accelerator is submitting a complete, professional package first time. If your works also fall under the Party Wall etc. Act 1996 (works to walls shared with neighbouring flats — common in conversions), that's a further parallel process with its own notices and timescales.

What happens if you skip it

• The freeholder can seek an injunction to stop works mid-project, or require reinstatement — undoing finished work at your cost.
• Persistent breach exposes the lease to forfeiture proceedings — rarely the endgame, but a powerful lever that freeholders' solicitors use.
• The most common consequence arrives years later, on sale: your buyer's solicitor raises enquiries, the missing licence surfaces, and you're negotiating a retrospective licence under time pressure with no leverage — typically at materially higher cost, sometimes with indemnity insurance as a messy fallback that many freeholders' enquiries now defeat.
• Your building insurance position can also be compromised where structural works were done without the consents the policy assumes.

We deal with licences to alter constantly — including retrospectively — and the pattern is universal: the retrospective route always costs more, in fees, in delay, and in negotiating position.

How this connects to your Siteline report

Your area report covers the public-law side — constraints, planning context, precedents. The licence to alter lives in your lease, which is private to your building, so no public dataset can check it for you. What we can tell you: if your address is a flat, assume a licence is needed for anything beyond decoration until your lease says otherwise. For lease review, application packages, and negotiation with freeholders' surveyors, enquiries route to Hampstead Chartered Surveyors — an RICS-regulated practice for which licence-to-alter work is core, day-in-day-out business, acting for leaseholders and freeholders.