How to ensure your loft conversion complies with building regulations

Read LABC's advice on loft conversions, the professionals you need to speak to, and watch a video on how Building Regulations relate to loft conversions: 

Loft conversions

Converting the space under the roof of your home can be a cost effective way of creating extra bedrooms or living areas. But not all lofts are suitable for conversion. As a first step you should check the following:

  • Height: Is there enough room in your loft to stand comfortably?  For your loft to be classified as a bedroom once converted you will ideally need a minimum of 2m headroom – but remember this will be after new floors, beams and panelling have been fitted, which may take up another 300mm of headroom.
  • Floor space: Is the floor area large enough to make a useable room?
  • Utilities: Would any chimneys, tanks, pipes or services require moving to create a usable space?
  • If your unconverted loft space is too low, too small or has too many utilities it may still be possible to convert it, but it will be much more complex (and expensive).  Talk to your local building control team for advice.

Get professional advice

Any loft conversion is a complex project, so you should get professional plans drawn up by an architect or building designer and get them approved by your local council’s building control team before starting work - you may also need planning permission so it's always best to check with your local authority Planning Department. The plans should cover:

  • Roof – structure (loading, supports and beams), materials, insulation and ventilation.
  • Access – stairs (angle, width and height), fire escape, handrails and bannisters.
  • Floors and walls – structure and strengthening, insulation and sound proofing.
  • Electrics, power and heating.
  • Windows and doors.
  • Fire safety – escape routes and smoke detectors.
  • Bathrooms – connection to water supply and drains, ventilation.


These can often provide much needed light in your roof space where planning restrictions apply on the size or number of dormers. There are many proprietary brands available, ranging from windows for means of escape in case of fire to windows giving access to open balconies. If you do intend to have a balcony you must ensure it is protected around the perimeter from falls and the decking is properly constructed to take foot traffic.

Storage spaces

You can use your existing loft space for storing lightweight household items without building control approval if you access the space by retractable ladder. It is good practice to fit some loose boarding to provide a flat surface for the items. Ceiling joists are generally not designed to support heavy loads. So if you plan to use your loft space for storing heavy items or install permanent flooring or a proper staircase you may need to apply to your local council for building control approval.

Further information

Read Loft conversions - When is a Building Regulations application needed? and Technical Guide: Guidance on loft conversions in a two-storey house (PDF)


Please Note: Every care was taken to ensure the information in this article was correct at the time of publication. Any written guidance provided does not replace the reader’s professional judgement and any construction project should comply with the relevant Building Regulations or applicable technical standards. However, for the most up to date LABC Warranty technical guidance please refer to your Risk Management Surveyor and the latest version of the LABC Warranty technical manual.


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