Licence to alter — the consent nobody tells flat owners about
Your lease is a contract — and the council was never the only gatekeeper.
By Planning Permission Checker Editorial · Reviewed by Savas Bulduk MRICS, Director, Hampstead Chartered Surveyors & Building Consultancy — RICS-regulated (Firm Reg. 923064)
Here is the most common mistake 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
| Internal wall removal in a flat | Planning: usually not · Licence: almost always |
| Combining two flats | Planning: often (Westminster has amalgamation policy) · Licence: yes, both leases |
| New rooflight / external alteration | Planning: often (flats have no PD rights) · Licence: yes |
| Like-for-like bathroom refit, same location | Planning: no · Licence: usually not |
The two regimes do not talk to each other
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.
| Combined freeholder surveyor + legal fees (you pay) | £1,500–£5,000+ |
| Your own advisers | On top |
| Timescale from a complete submission | 4–12 weeks |
Realistic numbers for a typical structural alteration
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.
The pattern is consistent: the retrospective route costs more than the timely one — in fees, in delay, and above all in negotiating position, because by then the freeholder knows the works are already done.
Where the free check stops, and who does what
The free check on this site covers the public-law side — conservation area and Article 4 designations at the property's own coordinates, and the planning route that follows. The licence to alter lives in your lease, which is private to your building, so no public dataset can check it for you. What can be said in general: if your address is a flat, assume a licence is needed for anything beyond decoration until your lease says otherwise.
From there the work splits between two professions, and it is worth knowing which you need. What the freeholder's surveyor actually assesses is a drawn and specified scheme — what is being removed, what replaces it, how floors, services and acoustic build-ups are handled — and preparing and submitting that package is architects' work. Hampstead Architecture and Planning are ARB-registered architects who prepare licence to alter packages alongside the planning permission and building-regulations approval the same works often need. Where the obstacle is the lease itself rather than the drawings — an absolute covenant, a freeholder's surveyor pressing hard on terms and costs, a Section 20 process running in parallel, or party wall notices to another flat — that is chartered-surveyor territory, and Hampstead Chartered Surveyors & Building Consultancy (RICS-regulated, Firm Reg. 923064) handle that side.
A licence to alter is between you and your freeholder, and no automated check can read your lease. The two professions do different halves of it — the architect prepares the package, the chartered surveyor deals with the lease and the freeholder's surveyor. Here is which one your situation needs.
Do I need a licence to alter if I have planning permission?
Who prepares a licence to alter application — an architect or a surveyor?
Can my freeholder just say no?
Who pays the freeholder's costs?
How long does a licence to alter take?
I did works years ago without a licence. What now?
Do flats have permitted development rights?
Also read
Terms used in this guide
Licence to alter · Leasehold · Party wall · Building regulations
Plain-English definitions · full planning glossary →
Planning Permission Checker provides planning and cost intelligence for early feasibility only. It is not legal, planning, valuation, architectural, structural, or surveying advice. All estimates are indicative and must be verified by qualified professionals before purchase, design, planning submission, or construction.
Cost estimates are indicative only — not a quotation. Final price depends on survey, specification, structure, access, party wall matters, VAT, professional fees, and contractor availability.
Planning outcomes are not guaranteed. Local planning authorities make final decisions.