Does My Loft Have Enough Headroom to undertake a loft conversion?

Ben Wilson's avatar

Ben Wilson | 10/04/18

This is one of the first questions you need to find the answer to when looking to convert your loft.  There are 3 main points that determine if your home has a suitable loft for conversion.

  • Current available head height
  • The angle, or pitch of the roof
  • The structure of the roof

Lofts with a minimum head height of 2.1m (from top of existing joists to underside of ridge, which should achieve 2m head height approximately) are usually seen as fit to convert, although obstacles like chimneys or water tanks, as well as the pitch of the roof, can also affect this decision.  

If the roof space is less than 2.1m, don’t throw away your dreams of a conversion, as there are other options available. You could:

  1. Raise the roof height - planning permission would be required for this option
  2. Lower the ceiling below

Lowering the ceiling height below or raising the roof height both have cost implications so you would need to factor these into the overall cost of your conversion.  

Raising roof height:

A loft conversion which increases the height of the roof, sometimes referred to as a 'roof lift' loft conversion is when the ridge line of your existing roof is increased in height by installing new attic trusses at the correct pitch and height to allow a conversion.

The existing gable walls, constructed from brick to match your property, are built up to meet the new ridge height, using a brick match where possible; if not other finishing options are available such as rendering etc.   This type of conversion is recommended for detached properties and bungalows with large lofts; however, insufficient standing room.

As a roof-lift alters the existing profile of your roof and increases the height it will require planning permission.

Lowering the ceiling below:

The existing ceilings to the upstairs rooms can be removed and the new structural floor can be constructed at a lower level than the original ceiling.  Many period properties in particular have rooms with high ceilings, which can make them ideal candidates to have their ceilings lowered in order to create a more spacious loft.   This operation, although it slightly compromises the original height of your upstairs rooms, creates the height required for a loft room. The downside to this process is that it is likely you will have to vacate your home while this element of the work is carried out.  

Where permission for a roof lift conversion will not be granted, typically within semi-detached or terraced houses, it may be possible for head room to be gained by lowering the ceiling of the floor below which would increase the height of the loft space.

At present majority of standard loft conversions (within 50m³ in detached or semi detached, and 40m³ in terraced homes) will fall within Permitted Development, however, should your home be a listed building or within a conservation area we would advise you speak to the local planning department.


For more information on loft conversion projects undertaken by Intotheloft and to contact us click here.

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