FHBS Implementation Timeline & Transitional Provisions
The regulations come into force on 24 March 2027, with transitional arrangements designed to give industry adequate time to adapt whilst maintaining momentum towards net zero. Here's what you need to know about the transition.
Critical Milestones
Regulations Laid in Parliament
The FHBS statutory instrument is laid. Updated Approved Documents and SAP 10.3 published. 12-month preparation period begins.
FHBS Comes into Force (Non-HRB)
New regulations and Approved Documents take effect for all non-higher-risk building work. 12-month transition period begins for projects already in the pipeline.
FHBS Comes into Force (HRB)
Regulations take effect for Higher-Risk Building work (including stages of HRB work) and work to existing HRBs. Gateway 2 applications must have been submitted before this date for transitional provisions to apply.
Transition Period Ends (Non-HRB)
Construction must have commenced on any non-HRB building relying on transitional provisions. After this date, all new non-HRB construction must comply with FHBS. Historic 2013 transitional arrangements also sunset on this date.
Standard Buildings (Non-HRB)
For non-higher-risk building work, relevant documents — an initial notice, building notice, or application with full plans — must be submitted to the relevant building control body by 24 March 2027. Construction must then commence on the building by 24 March 2028. If both conditions are met, the building may be completed to the previous Part L 2021 standards. These arrangements apply on a building-by-building basis, not to whole sites.
Higher-Risk Buildings
HRBs (at least 18m/7 storeys with 2+ residential units, or care homes/hospitals) must go through the Gateway process managed by the Building Safety Regulator. Given the additional complexity and time requirements, separate provisions apply: the amending regulations come into force on 24 September 2027, and a valid Gateway 2 application must be submitted before that date. Construction must begin within 3 years of the application, as required under the Building Safety Act.
Sunsetting Historic Arrangements
The 2013 transitional arrangements — which allowed continued use of 2010 Part L standards on some large sites — are being given an end date. Building work relying on these provisions must commence by 24 March 2028, or comply with standards introduced after 2010. However, for HRB work, the 2013 and related 2021 transitional arrangements are maintained, reflecting the longer build times of these complex projects.
Planning Permission Implications
Some developments may need to amend existing planning permissions to accommodate FHBS requirements — for example, solar PV installations, heat pump placement, or fabric changes. The government has noted that decisions on whether changes are non-material are a matter for Local Planning Authorities, and existing planning routes provide mechanisms for considering amendments.