Can you convert the loft of a flat you are buying?

Who owns the loft above a flat?

Often not the flat owner. Flats are generally leasehold, which means ownership is for a set period, and the leaseholder (the "lessee") owns the area inside the flat, not the building or the land it stands on.

The loft space is therefore often not part of the lease. It may be common property of all the leaseholders, or it may belong to the freeholder.

What permissions are needed to convert a loft in a flat?

A loft conversion in a flat needs legal permissions from the appropriate bodies before work starts. These can include:

• planning permission;
• building regulations approval;
• the freeholder's consent (usually the landlord).

Unlike house owners, flat owners may be unable to use permitted development rights (a system granting automatic planning permission for certain types of development), so planning permission is likely to be needed for loft conversions in flats.

Buying a home that has been altered? Get a survey price for the home you are buying.

Is the loft structurally suitable for conversion?

Not every loft is structurally able to take a conversion. The viability of the structure should be assessed by a skilled professional before any commitment is made.

• The angle of the roof.
• The head height available.
• The structural integrity of the existing ceiling joists.
• Whether the loft can carry the extra weight of the conversion.

What about fire safety?

Fire regulations are a key consideration. Fire safety measures such as a fire-resistant door are likely to be needed, and possibly a sprinkler system.

How much does a loft conversion in a flat cost?

The cost varies significantly with the size of the loft, the materials used and labour charges.

Buyers should weigh the conversion costs against the likely increase in the property's value, and a surveyor can help assess the potential value after conversion.

What to do next

1. Check the lease to see whether the loft space is included, or whether it belongs to the freeholder or is shared with other leaseholders.
2. If it is not included, find out whether the freeholder will agree to include it, and at what payment.
3. Confirm the planning permission, building regulations approval and freeholder's consent that will be needed.
4. Have a skilled professional assess the roof angle, head height, ceiling joists and load capacity.
5. Allow for fire safety requirements, such as a fire-resistant door and possibly a sprinkler system.
6. Compare the likely conversion cost with the likely increase in value.

What a survey can — and cannot — tell you

A building survey provides an informed assessment of the visible condition of a property. Inspections are non-intrusive and limited to areas that are accessible at the time of inspection.

For a buyer considering a loft conversion in a flat, a building survey can show the scope for improvements and conversion, the suitability of the structure, and any potential legal or safety issues. It can uncover hidden problems, but also highlight opportunities for conversion that are not obvious.

• The visible roof structure, including its angle and the head height in the loft, where it is accessible.
• The visible condition of the ceiling joists.
• Safety issues relevant to a conversion, such as fire safety.
• Points that need raising with a legal adviser, such as ownership of the loft space.

However, there are limitations to what a survey can determine without intrusive investigation.

• Whether the structure can carry the extra weight of a conversion, which needs structural analysis.
• Whether the loft is included in the lease or whether consent will be given, which are legal matters.
• Whether planning permission or building regulations approval will be granted.
• Loft areas that are not accessible on the day.

Where higher-risk indicators are identified, further specialist or intrusive investigation may be recommended.