Under English leasehold law, a leaseholder owns a long lease of the flat (typically 99-999 years) but does not own the structure or common parts of the building — these remain with the freeholder. Before carrying out any works that affect the structure, the demise boundary, or shared services, leaseholders generally need landlord's consent and a formal Licence to Alter.
Carrying out works on a leasehold flat without the correct consents is one of the most common and potentially costly mistakes leaseholders make. Works carried out without consent can constitute a breach of the lease — giving the freeholder grounds to require reinstatement, claim damages, or in extreme cases, pursue forfeiture proceedings.
This guide explains what consents are required, how to obtain a Licence to Alter, when Section 20 applies to building-wide works, and how the Building Safety Act 2022 has changed the landscape for works in high-rise buildings.
What Works Require Consent?
- Structural alterations — Removing or altering load-bearing walls, altering the floor or ceiling structure, creating new openings.
- Wet room or bathroom installations — Works involving water supply or drainage connections affect shared services and require consent.
- Extensions to the demise — Any works that extend the flat's footprint (e.g., loft conversions where the loft is owned by the freeholder).
- Changes to external appearance — New windows, doors, external finishes, or satellite dishes typically require consent as they affect the building's appearance.
- MVHR or heat pump installations — These affect shared services and penetrate the building envelope — consent almost always required.
The Licence to Alter Process
- Check the lease — Identify the precise consent clause (typically "not to make alterations without prior written consent, not to be unreasonably withheld"). Some leases prohibit certain works outright regardless of consent.
- Prepare drawings and specifications — The freeholder's surveyor or solicitor will require detailed plans, structural calculations (if relevant), and contractor details.
- Submit a formal application — Write to the managing agent with full plans, proposed start date, contractor's insurance certificate, and method statement.
- Pay the Licence to Alter fee — Freeholders and managing agents typically charge for reviewing applications. These fees must be reasonable and authorised by the lease. Check the service charge schedule.
- Obtain the Licence — Once granted, the Licence to Alter will specify conditions (e.g., reinstatement at lease end, professional indemnity requirements, completion certificate obligations).
- Notify on completion — Most licences require written notification of completion and submission of as-built drawings, Building Regulations completion certificate, and any warranties.