Establish what the lease actually allows
GOV.UK explains that the lease sets the conditions you have agreed to, including whether permission is needed for alterations. Start with the complete lease and any later variations, rather than relying on a sales description or what another flat owner was allowed to do. [2]
Ask a property solicitor to identify the relevant alteration clauses and the extent of the premises included in your lease. Request a written explanation of any restriction that changes the proposed design or requires a separate agreement.
The flat is not necessarily the whole structure
LEASE distinguishes the parts included in the lease from retained premises owned or controlled by the landlord. A roof, external wall, structural wall or shared floor can fall into the latter category. Permission to alter your own flat should not be assumed to grant rights over those areas. [1]
For a loft or ground-floor extension, ask specifically about the roof space, garden, external structure and any proposed service route. Mark those areas on the same drawings used for the consent enquiry so that the parties are discussing the same boundary and works.
Obtain a clear written consent
A lease may prohibit alterations, permit them, or make them conditional on written consent or a licence. The wording needs interpretation; do not assume every refusal is unlawful or every prohibition can be overcome by paying a fee. [1]
Prepare a coherent request with a description of the works, the relevant drawings and a proposed timetable. Ask the landlord or managing agent to specify any further engineering information, contractor details, insurance evidence or inspection arrangements needed. Keep the consent with the drawing revisions to which it relates.
Do not treat acknowledgement of the request, an informal conversation or silence as the written approval your lease may require.
Allow for costs and shared-building arrangements
Where the lease permits relevant consent expenses, the landlord may charge for legal or surveyor involvement, subject to the applicable rules on administration charges. Obtain a breakdown before accepting an open-ended allowance. [1]
Buildings insurance for flats may be arranged through the freeholder, and the cover depends on the policy. Ask who must notify the insurer and what confirmation is needed before work starts; your own contents policy is not a substitute for checking the building's arrangements. [3]
Complete the other approvals separately
The planning route for a flat is not simply the householder permitted development route for a house. Building control requirements also need a separate check. [4] [5]
Before authorising work, ask the adviser to reconcile the landlord-approved scheme with the planning and technical drawings. A change agreed by one decision-maker should be checked against the other consents rather than assumed to update them automatically. Obtain legal advice on disputed or unclear lease terms before proceeding.