Skip to content

Additional storeys/Extending upwards

Is building regulations approval needed for additional storeys/extending upwards?

Building regulations approval is required to add additional storeys to an existing building to make it into a liveable space.

This section provides guidance for adding an additional storey to an existing house which is no more than two storeys high. Requirements for additional storeys to houses over three storeys or flats will be similar but may be more extensive and possibly extend to other parts of the building.

The regulations will be applied to ensure, for example:

  • the structural strength of the new floor is sufficient
  • the stability of the structure (including the existing roof) is not endangered
  • safe escape from fire
  • safely designed stairs to the new floor
  • reasonable sound insulation between the conversion and the rooms below.

Find a Trade Professional

Use our partner directories from CIAT, FMB, RIBA, or RTPI to find an chartered architectural technologist, builder, architect or planning consultant to help with your project or development.

Find a professional


Useful links

Make an application Planning consultancy calculator


    Further information

    The following common work sections give an indication of several other elements normally required to satisfy the requirements of the Regulations when building an additional storey on to a house:

    1. https://www.planningportal.co.uk/permission/common-projects/doors-and-windows/building-regulations
    2. https://www.planningportal.co.uk/permission/common-projects/drains-and-sewers/building-regulations
    3. https://www.planningportal.co.uk/permission/common-projects/electrics/building-regulations-general-information
    4. https://www.planningportal.co.uk/permission/common-projects/external-walls
    5. https://www.planningportal.co.uk/permission/common-projects/internal-walls/what-building-regulations-apply-to-internal-walls
    6. https://www.planningportal.co.uk/permission/common-projects/kitchens-and-bathrooms/building-regulations-need-for-additional-ventilation
    7. https://www.planningportal.co.uk/permission/common-projects/roof/building-regulations-work-to-an-existing-roof

    The Planning Portal is delivered by PortalPlanQuest Limited which is a joint venture between TerraQuest Solutions Limited and the Department for Levelling Up, Housing and Communities (DLUHC). All content © 2024 Planning Portal.

    The Planning Portal is delivered by PortalPlanQuest Limited which is a joint venture between TerraQuest Solutions Limited and the Department for Levelling Up, Housing and Communities (DLUHC). All content © 2024 Planning Portal.