Licence to Alter (2026): Getting Landlord Consent for Building Works in a Leased Property

What the alteration covenant actually says

Almost every commercial lease contains a covenant restricting alterations. The exact wording matters more than tenants usually realise. There are two common formulations:

Absolute prohibition: "The tenant shall not make any alterations to the demised premises." No amount of negotiation with the building manager gets you round this—only the landlord (and any superior landlord) can grant a formal consent, and they are entitled to refuse without giving reasons.

Qualified prohibition: "The tenant shall not make any alterations without the landlord's written consent, such consent not to be unreasonably withheld." Under section 19(2) of the Landlord and Tenant Act 1927, a qualified covenant automatically carries an implied proviso that consent cannot be unreasonably refused for improvements. "Improvement" is assessed from the tenant's perspective—a mezzanine floor that suits a warehouse occupier almost certainly qualifies even if the landlord would prefer the space kept clear.

Check your lease before doing anything else. If the restriction is absolute, your solicitor will need to negotiate a variation or a standalone consent at the landlord's full discretion.

Structural versus non-structural works

The distinction is not just architectural—it determines the formality of consent required and the reinstatement obligations at the end of the term.

Structural works include anything affecting the load-bearing fabric: removing or cutting into walls, columns or beams; new floor penetrations; changes to the roof structure; installing mezzanine floors with independent foundations. Leases almost always treat structural works as subject to a separate, stricter regime. Some leases prohibit structural alterations absolutely even where non-structural works only need a qualified consent.

Non-structural works cover fit-out and partitioning that do not touch the building fabric: demountable partitions, raised access floors, suspended ceilings, internal joinery, M&E installations tied only to the tenant's own supply. Many leases permit these with a simple letter of consent rather than a full licence, provided they are removed at lease end and any make-good obligation is met.

Borderline cases—such as cutting a new doorway through a non-load-bearing but fire-rated wall—will usually need a structural engineer's sign-off before the landlord will consider consent.

The difference between a letter of consent and a surveyor's licence

A letter of consent is a short document (sometimes two pages) in which the landlord confirms permission for defined, low-impact works. It sets out the scope, confirms any conditions (insurance uplift, building regulations compliance), and records the reinstatement obligation. Appropriate for minor fit-out works where the parties trust the description of scope.

A surveyor's licence to alter is a full-form legal instrument, typically drafted or reviewed by the landlord's surveyor and solicitor. It will include:

• Approved drawings and specification schedules incorporated by reference
• An obligation to carry out works in a good and workmanlike manner and to the landlord's surveyor's reasonable satisfaction
• A condition that all statutory consents (planning permission, building regulations approval under the Building Regulations 2010) are obtained before works commence
• A right for the landlord's surveyor to inspect during and after works
• Reinstatement obligations—specifying which alterations must be removed at lease end and the standard of making good
• An indemnity from the tenant for any loss the landlord suffers from the works
• Costs—who pays for the landlord's solicitors and surveyors (almost always the tenant, under the "tenant pays all costs" principle standard in commercial leases)

For anything structural, or any works costing more than a few thousand pounds, insist on the full licence rather than an informal letter. The approved drawings are your protection if a later dispute arises about what was actually sanctioned.

The superior landlord chain

Multi-let buildings and most City of London offices sit within a headlease structure. The immediate landlord may not own the freehold—they may themselves be a tenant of a superior landlord or freeholder. This matters because:

1. The headlease will almost certainly contain its own alteration covenant binding the mesne landlord.
2. Your landlord cannot grant you rights they do not themselves have—if the headlease prohibits structural alterations, your lease-level consent is worthless without superior landlord consent running in parallel.
3. Obtaining superior landlord consent can add weeks to the timetable and an additional layer of costs.

A well-drafted licence to alter will include a condition precedent that any necessary superior landlord consent has been obtained before works commence. Where the article's primary link to superior landlord consent forms comes in: having a clean paper trail from each tier of the ownership structure protects the tenant if ownership changes hands mid-lease.

Always ask your landlord at the outset whether any superior landlord or mortgagee consent is required. The answer should be confirmed in writing.

The reinstatement obligation

Reinstatement is one of the most overlooked—and most expensive—clauses in a licence to alter. At lease end, the landlord can require the tenant to strip out all alterations and return the space to its original condition. Failure to do so gives the landlord a claim for damages assessed by reference to the cost of reinstatement, not the diminution in market value of the property.

Three points to negotiate hard on:

Elective reinstatement: Ask for a clause that gives the landlord the option—exercisable on notice before lease expiry—to elect whether reinstatement is required. If they do not serve notice, the alterations are left in. This is increasingly common in London office fit-outs where landlords often prefer to inherit a well-fitted space.

Partial reinstatement: Where works include both structural changes (mezzanine) and aesthetic fit-out (partitioning, decorations), push to limit the reinstatement obligation to the structural elements only. The landlord has a weaker case for stripping out partitions that have no lasting effect on the fabric.

Condition baseline: Agree and record the condition of the premises at the date of the licence—ideally with a photographic schedule. Disputes about what "original condition" means are much easier to resolve when there is contemporaneous evidence.

Statutory consents—do not skip them

A licence to alter does not replace the requirement for statutory approvals. Depending on the works:

• Planning permission may be needed if the works constitute development under the Town and Country Planning Act 1990, or if the building is listed or in a conservation area.
• Building regulations approval is required for structural work, changes to fire compartmentation, electrical installations, and significant M&E alterations—all under the Building Regulations 2010 (SI 2010/2214) as amended.
• Fire safety compliance under the Fire Safety Act 2021 and the Fire Safety (England) Regulations 2022 is mandatory for shared buildings, and works affecting fire doors, means of escape, or compartmentation must be signed off.
• Listed building consent if the premises are listed—separate from and additional to planning permission.

The licence to alter should explicitly require that all necessary consents are obtained before work starts and that copies are handed to the landlord. Some landlords include a condition that the licence becomes void if works commence without the required consents in place.

Practical timetable and costs

Expect the consent process to take four to twelve weeks from initial request, depending on complexity and whether superior landlord sign-off is needed. Budget for:

• Preparation of proposed drawings and specification (your cost, via your architect/engineer)
• Landlord's surveyor fees for reviewing the proposal and monitoring the works (typically £2,000–£8,000 for a straightforward fit-out; more for complex structural work)
• Landlord's solicitor fees for preparing or approving the licence (typically £1,500–£4,000)
• Any planning or building control fees

Submit a written application with full drawings as early as possible. Landlords who receive a vague verbal request invariably take longer to respond—and a formal application triggers the section 19 implied duty not to unreasonably withhold consent for improvements.

What happens if you proceed without consent

Carrying out alterations in breach of a qualified covenant without consent does not automatically trigger forfeiture—the breach must be capable of remedy and the landlord must first serve a notice under section 146 of the Law of Property Act 1925 before proceedings. However, that process gives the tenant a route to relief from forfeiture only if the breach is remedied. An absolute-covenant breach is more serious: courts have been willing to grant forfeiture for clear, deliberate breaches even where the tenant remedies the physical works.

Beyond forfeiture, the landlord can seek damages for diminution in value and costs of reinstatement, and a court injunction to halt works mid-project. The legal and commercial exposure far outweighs the inconvenience of getting the licence in place before you pick up a drill.

Key checklist before works start

1. Read the lease: identify whether the alteration covenant is absolute or qualified, and whether structural works are treated separately.
2. Check the ownership chain: ask the landlord in writing whether superior landlord or mortgagee consent is required.
3. Engage a commercial property solicitor and (for structural or significant works) a building surveyor.
4. Submit a formal written application with approved drawings and specification.
5. Agree reinstatement terms in the licence—elective if possible, limited to structural alterations at minimum.
6. Obtain all statutory consents before site mobilisation.
7. Keep a copy of the signed licence and approved drawings on site throughout the works.

A licence to alter, properly drafted and negotiated before work starts, costs a fraction of the dilapidations or forfeiture litigation that follows when it is skipped.