When it comes to adding space quickly and efficiently to a home, the loft is often the best place to start. It is the least disruptive area of a home to work on, and it is affordable. It is also a great way to add up to 25% to the value of a home.

It is important to plan the work and the design of the room well though, and naturally to use the services of a good local builder.

The basics

Typically, the way to determine whether a loft space is suited to conversion is to measure 230cm from the floor to the roof at the room’s tallest part. Ideally, half of a loft space should allow this headroom.

Steeply pitched roofs, often seen in pre-war buildings will easily give enough space. However, there will be structural considerations to work into the plans too. There will often be less structural work on converting a loft than there will be in converting or extending into other areas of the house. Once again, a reputable builder will advise on the best way forward.

Planning permission

In most cases, loft conversions do not need planning permission. However, it is always good to check with the local planning office before going ahead. A good builder in the area will be able to provide advice on this too. Checking the rules on party walls, for terraced homes, is essential too.


One important aspect to plan for is the staircase. If a loft room is to be used as a permanent bedroom, a permanent staircase is a necessity. The dimensions of the main staircase do not have to be followed though. Where space is restricted, a spiral staircase delivers a workable and good-looking solution.

Building regulations

Where the converted space is to be used as a living area, it is essential that regulations in regards to fire safety, ventilation, energy efficiency and lighting are met. This is separate to planning consent, and the local authority will approve the plans accordingly. Again, experienced local builders will be able to help here.


Another necessity is adequate insulation. As a rule, rigid insulation materials and fibre blankets are used. These should be between 150 – 250mm thick as a minimum, but the more the better. These will satisfy the needs in regards to thermal and fire insulation, and also help with sound proofing.


An important part of the design of a loft conversion is to choose the right windows. Creating light and ventilation, they will also open up a space and make it more livable. Dormer windows are ideal for this, and create additional space boxing out the pitch of the roof, though planning permission may be needed. Opening sloped skylights are simple and affordable to install.

Contingency budget

As with any major house renovation project, a loft conversion may require extra time and additional works as the fabric of the existing building is revealed. As such, having a contingency budget is important. Most likely, this will be needed for plumbing and electrical works, which should be discussed with the builder at the outset.