We can confirm that a new regulatory change will impact Building Control applications for new dwellings across England and Wales.
The Building Safety Levy (BSL) comes into effect on 1 October 2026. This is a UK Government charge applied to certain new residential developments and collected by local authorities to help fund the remediation of historic building safety defects.
Generally, a charge will arise where new chargeable residential floorspace forms part of a development of 10 or more new dwellings (or 30 or more bedspaces in Purpose-Built Student Accommodation / PBSA). However, it is crucial to note that a smaller building control application can still be chargeable if it forms part of a wider development that meets this threshold.
To ensure projects remain compliant and progress without delay, here is an overview of the new reporting requirements at Building Regulations stage.
The Two-Stage Information Requirement
For applications that include one or more new dwellings, applicants and developers will be required to submit specific BSL data to Building Control at two distinct project milestones:
Stage 1: Initial Application
When submitting the initial Full Plans application, the following details must be supplied:
The number of new dwellings proposed (including those created via conversion or change of use) or the number of new bedspaces in Purpose-Built Student Accommodation (PBSA).
The planning permission reference, prior approval details and status, or confirmation if proceeding under Permitted Development rights.
Confirmation of whether the works are, or form part of, a wider scheme anticipated to yield 10 or more new dwellings.
Stage 2: Notification of Commencement
When the first plot reaches the statutory definition of "commencement", BSL information is required for all works covered by that Building Control application—even if remaining plots have not yet commenced. This notification must include:
Confirmation of the planning permission or prior approval under which the works are proceeding, noting any variations or formal amendments since the initial submission (or confirmation if proceeding under Permitted Development).
Where a levy charge may be due: the number of exempt dwellings, the Gross Internal Area (GIA) of each chargeable dwelling and relevant communal areas, and whether the development qualifies for a discount as a previously developed (brownfield) site.
Supporting evidence for the information supplied, such as architectural floor plans with measured GIA areas clearly demarked, planning decision notices, relevant Section 106 agreements, or evidence supporting a brownfield site claim.
Where no levy is payable, a clear justification explaining why the charging conditions are not met, alongside supporting evidence. This applies to single dwellings, developments below the 10-unit threshold, and schemes claiming specific exemptions.
When is the "Commencement Stage" legally met?
Under updated UK Building Regulations (Regulation 46A), site clearance, breaking ground, or digging trial pits is no longer sufficient to legally constitute commencement. The milestone requires substantive structural progress depending on the building type:
Standard New Buildings: Work is legally regarded as commenced only when the sub-surface structure of the building—including all foundations, any basement level, and the complete ground-floor structure—has been finished.
Complex Buildings: For buildings constructed on shared podiums or with multiple basement levels, work is commenced when the foundations supporting the building and the structure of the lowest floor level are fully completed.
Other Building Works: For projects that do not fall into the categories above, commencement is reached when 15% of the overall proposed building work is completed.
Why Smaller Projects Still Need to Report (£0 Charge)
Standard forms will be available to supply the required information at both the Initial Application and Commencement stages.
Crucially, commencement-stage information is mandatory even where the expected levy charge is £0 (for example, a single bespoke dwelling or a scheme below the 10-dwelling thres
hold). Supplying this information enables the collecting local authority to formally issue either a Levy Liability Notice or a Notice of No Charge.
What This Means for Your Project
While many architectural projects will fall below the threshold and remain non-chargeable, complying with the administrative process is vital. Failure to provide Building Control with the correct BSL information at the appropriate stages will cause administrative delays and, crucially, will prevent the Local Authority or Registered Building Control Approver from issuing a Completion Certificate.
Our architectural practice is integrating these BSL documentation checkpoints directly into our technical design and Building Control packages (RIBA Stage 4) to ensure a smooth transition from drawing board to site.