Loft conversion

Planning a loft conversion

Many homeowners choose to add a loft conversion to their home to increase the number of bedrooms or maximise their existing living space. A loft conversion creates extra space for a bedroom, office or playroom without the bother of moving house.

There are four main types of loft conversion:

  • Rooflight - A popular option that doesn’t involve structural alterations, providing there is sufficient height in the original loft space.
  • Dormer - There are a few different types of dormer which suit specific properties. A dormer is a popular choice as it easily creates extra height and floor space.
  • Mansard - A choice for bigger loft adjustments which due to the nature of the conversion shape requires structural changes to the property. 
  • Hip to gable - An extension from the sloped roof out to the external wall.

A planning consultant may help with the smooth running of your loft conversion project. To find an accurate consultancy quote, explore Studio Charrette's calculators.

Your existing loft

Which conversion type you choose will depend largely on your existing loft dimensions and structure. Loft conversations require a minimum height of 2.2 metres and building regulations must also be adhered to.
Homes built after the 1960s are more likely to have a roof truss rather than timber framed roof and in this instance may require structural support. 

Your chosen style of loft conversion will also depend on obtaining planning consent if necessary and of course, your budget.

Use our mini guide to find out about planning permission for loft conversions.
Find out about building regulations for loft conversions on our common projects page.

Party Walls

If your property is a semi-detached or terraced house, you will need to advise adjoining neighbours of your plans under the Party Wall Act 1996. 

Find out more about Party Walls


Loft conversion companies offering a full planning service will be able to advise you on the placement of loft access.  If there is not adequate space for a full stairs, a space saving stairs may be an option. 

For general safety reasons, there are specific criteria that a stair should be designed to. Further information on fire safety can be found in Approved Document B (Fire safety) - Volume 1: Dwellinghouses

Insulating your loft

The insulation in your loft must meet the minimum energy efficiency rules set out in Approved Document L1B: Conservation of fuel and power in existing dwellings (PDF)

Find out more about efficiently insulating your loft.