FAQ

1. I am thinking about converting my loft into a bedroom, what do I need to consider?
1) Is there enough head height?
People are often disappointed by how much space they have to actually stand up in, whilst there may seem a lot of room in the loft space to walk around, the joists that you are walking on are technically only for very light loads usually only around 75mm deep and to support the ceiling plasterboards. A second set of joists needs to be placed next to the ceiling joists to support the floor loads and they may raise the deck by at least 150mm more so if there is a no load bearing walls below.

The roof needs to be upgraded with insulation to become a habitable room, which will amount to around at least 125mm thick, some of which may be fitted between the rafters, but there needs to be an air gap of 50mm left between the insulation and the felt to prevent moisture building up.

So you may find that you lose around 250mm of head height when the loft conversion is carried out.

Don’t forget you’ll have to accommodate a staircase leading up into the loft – to make the best use of space the new staircase should rise above the old one and not from within an existing bedroom, but this is not always practical, because you need to maintain a 2.0m head height above the existing and new staircase and to achieve this, the bottom of the stairs needs to start directly above the existing stair, and this is usually inside and existing bedroom.

Also consider whether there are water tanks and plumbing in the loft, because the heating and hot water system may have to be replaced with a sealed system.
2. What is the difference between planning and building control?
With all building work, the owner of the property (or land) in question is ultimately responsible for complying with the relevant planning rules and building regulations.

​If you want to carry out building work, you may require both Planning Permission and Building Regulations approval. Planning and Building Control are separate; if you get one you are not guaranteed the other.


Planning has more to do with the appearance of a building or an extension to a building and how it relates its surroundings.

Building Control aims to see that the building satisfies its functional requirements and provides reasonable health, safety and comfort for the building users.

3. Do I need planning permission to convert my garage into a habitable room ?
This is usually permitted development and planning permission isn't generally required, unless the work involves enlarging the building or altering the roof structure - for example changing it from a flat roof to a pitched.

A new housing development or in a conservation area may have permitted development rights removed from some properties with regard outbuilding and garage conversions and therefore you should contact your local planning authority before proceeding.

Whenever work is proposed to a listed building, listed building consent may be required.

For more information on Listed building consent, please read news section:

You will need to obtain Building Regulations approval for the work, however to ensure the conversion meets the current building regulations in particular, fire safety/means of escape in the event of a fire, thermal efficiency, and ventilation
4. What is a U value quoted on parts of a building
A U value is a measure of how effective a material or a collection of materials is an insulator for example the combined components that make the outside wall. It is expressed in W/m2k, and shows the amount of heat lost in watts (W) per square metre of material (for example wall, roof, floor etc.) when the temperature (k) outside is at least one degree lower. The lower the u value, the better the insulation provided by the material.
So when it is cold outside and warm inside, U-value is the measurement of how quickly the heat from the inside leaks to the outside.