The government has granted permitted development rights for the construction of new dwellings on top of existing blocks of flats or commercial buildings. Planning permission is no longer required for these upward extensions.
The government hopes that these new permitted development rights will help increase housing supply in England.
However, the ministry is warning local councils not to abandon their duties with regard to policing building regulations.
The circular letter is headed The application of building regulations where additional storeys are provided to existing buildings and dated 10th August 2020. It is signed by Frances Kirwan, deputy director of the ministry's building safety portfolio, and says:
“Each case must be considered on its own merits, but it is likely that where additional storeys are added to an existing building, some work on the original part of the building will be necessary. This may not always be set out in the approved documents and building control bodies should consider carefully the application of the building regulations to these projects. The regulations pose a series of questions that must be considered, the first being whether the work is deemed to be controlled and notifiable. We cannot envisage a situation where the addition of new storeys to a building would not be notifiable building work.”
The councils are told to consider how and whether adapted buildings meet building regulations, making specific mention of regulations 4(1), 4(3), 5, 6 and 28 among others.
On the latter, it says: “Where the existing building has a useful floor area over 1000 m2 consequential improvements to the energy performance may be required. This requirement applies to the entire building and will therefore capture many medium to large sized buildings.”