England’s Building Safety Regulator has issued an information note to principal accountable persons and building owners on potential structural risks associated with reinforced concrete transfer slabs. Published on 19 December 2025, the notice applies in England and sets out a proportionate approach while further technical advice is developed.
A transfer slab is a floor arrangement where a column bears on a slab without a supporting column directly beneath; the slab transfers the load to supports below. The approach has been used in the UK for more than 25 years, often in mixed‑use schemes where floor grids change, and not all buildings using this feature will experience issues.
In November 2024 the Institution of Structural Engineers published design guidance for new transfer slabs; the document does not cover assessment of existing slabs. BSR says the publication has prompted questions about the adequacy of older design methods, particularly in relation to punching shear.
Punching shear is a localised failure in which concentrated load can cause a column to punch through a reinforced concrete transfer slab, potentially leading to a partial collapse. BSR reports no known UK building collapses arising from this mechanism.
For residential buildings, the presence of a transfer slab alone does not justify decant. Building owners should seek professional advice where there are visible signs of distress such as cracking, and weigh any decant against the assessed level of risk, keeping residents in their homes where it is safe to do so.
BSR has commissioned independent research, consulted its Building Advisory Committee and is working with the housing department (referred to in the note as MHCLG) to understand how risks in existing buildings can be identified and managed proportionately. Further advice will follow, with updates via BSR bulletins and the building safety campaign site.
This information sits alongside existing legal duties for higher‑risk residential buildings. Accountable persons and the principal accountable person must assess and manage structural safety risks, keep the golden thread of building information, report safety occurrences to BSR and operate a mandatory occurrence reporting system.
Owners should confirm whether their buildings include transfer slabs and be ready to take proportionate steps where concerns arise. For higher‑risk residential buildings, ensure structure and fire safety information submitted at registration is kept up to date and report any significant safety occurrence without delay.
The regulator’s message is to avoid unnecessary disruption while competent assessments are undertaken. Decisions about temporary decant should be evidence‑based and account for the impact on residents, with a presumption to maintain occupation where a safety assessment supports this.
Further technical detail and regulatory direction will follow as the commissioned research concludes. In the meantime, owners and principal accountable persons should subscribe to BSR updates and monitor the campaign site for subsequent instructions.