Loft Conversions

If you are thinking about converting your loft to create an additional room then you will need to apply for Building Regulation Approval.

You may also need Planning Approval if you live in a conservation area and / or are installing a dormer window (note: Chris Froggatt.com recommends that you contact your Local Planning Authority who will confirm if a Planning Application will be required as different Local Authorities have different opinions).

This information only applies to two storey houses where the new storey is not more than 50sq m and does not create more than two habitable rooms and the existing ridge is not raised.

This information tells you about three basic requirements. If you can't achieve these then you will not be allowed to carry out your conversion. If in doubt contact Chris Froggatt.

1) DOES YOUR STAIRCASE DISCHARGE TO A FINAL EXIT?

At ground floor the stairs must be in a hall (a) or offer an alternative escape (b) to a final exit (door). Therefore if you have an open staircase it will have to be enclosed.

2) CAN YOU PROVIDE A SUITABLE ESCAPE WINDOW FROM THE NEW SECOND FLOOR?

Existing purlins are often in the way when positioning an escape window. If the purlin needs moving to achieve the 1.7m dimension then structural design will be needed.

An escape window can also be fitted into a gable wall if there is access below for ladders.

3) CAN YOU ACHIEVE A SUITABLE HEAD HEIGHT OVER THE NEW STAIRS?

Another key area is the headroom of the staircase. It should be at least 2 metres although it can be reduced if the headroom is limited.

Where there is not enough space to achieve 2m headroom, reduced headroom of 1.9m measured at half the stair width will be satisfactory.

A standard staircase should be installed but again if space is limited an alternating tread stair can be used. This type of stair relies on familiarity and regular use for reasonable safety ask to see one before you commit yourself.

The diagram below shows you what will also be needed to protect the second floor if you can't escape down the stairs:

ITEM 1
Existing stair (in ground and first floors) to be enclosed in fire resisting construction (eg plasterboard and stud or block) and to lead to outside through alternative (and separated) rooms to outside. Doors to be self closing (not full fire doors). Glass in partitions to be fire resisting (glass to bathroom need not be).

ITEM 2
New stair can either 2a) continue up in existing stair enclosure (eg alternating stair from landing) or 2b) it can be in an extension of the existing stair enclosure.

If 2a) the the fire door to the new storey will be at the top. If 2b) then the fire door can either be at the top or on the first floor landing.

ITEM 3
The new floor must have 30 minute fire resistance.

ITEM 4
Escape windows should be provided for each habitable room with a clear openable area not less than 0.33sq m, and at least 450mm wide and 450mm high.

ITEM 5
Ensure there is access and space to set ladders below.

ITEM 6
Install an automatic smoke detector and alarm system based on mains operated, linked smoke alarms.

If you can adapt your house to satisfy these requirements the you will be able to convert your loft. Contact Chris Froggatt.com to cover a host of other regulations such as thermal insulation and structural alterations eg. dormer windows, floors, etc.

LOFT CONVERSIONS

Converting existing roof space can be the easiest and most cost effective way of increasing living accommodation in many houses. Up to 30% extra space can be gained by converting the loft in a two storey home, and this figure can rise to 70% in bungalows.
Rooms in the roof provide attractive, flexible living space ideal for extra bedrooms, studies, playrooms and even bathrooms.

The first step is to assess the feasibility of the project. Some shapes and forms of roof lend themselves more readily to conversion than others. However, not all types of roof structure are suitable for conversion. Until the 1960's most roofs were made up by carpenters on site. This traditional roof construction is ideal for loft conversions. Post 1965, the use of modern trussed rafter construction means shallower pitches and more struts - a type of roof structure that generally cannot be converted.

The size and shape of the existing roof space will determine whether it can be used for living accommodation. A ceiling height of 2.3m is the preferred minimum for habitable rooms, although this height need not be maintained over the whole floor area. Lower room heights may be acceptable for bathrooms, corridors, kitchens or storage.

Having established the feasibility of converting the roof space, it is essential to check the condition of the existing structure before any design work is undertaken. Any roof inspection should include: the condition and dimensions of the timber structure; the type and condition of external and internal wall construction; the presence of internal load bearing wall support; the type and condition of any party (separating) wall; and the position and size of existing water storage tanks and services.

Loft conversions may not require planning permission, but it is always advisable to contact the local planning officer. Any conversion which alters the shape of the roof (such as installing a dormer window) changes the use of the building, or is within a conservation area, or a listed building will always require planning permission. All loft conversions must comply with the building regulations / standards.

There are various areas to be considered in order to comply with the building regulations - structural stability, means of escape, fire resistance, spread of flame, thermal insulation, ventilation etc.

Access to the converted loft must be via a stair which conforms with the requirements of the appropriate regulations. There is no restriction on the type of staircase, which may be a straight flight, winding staircase, quarter landing or half landing. But, stairs must also conform with requirements for escape and will need some form of fire protection. Loft ladders may not be used to provide access to rooms in the roof, other than for storage accommodation, for example.

An emergency escape window must also be fitted in any habitable room in an upper storey which only has one escape route. The specification of the window is particularly important in loft conversions. Not only are they crucial in providing ventilation and light, but they can make a real difference to the quality of the living space created in the roof.

Roof windows provide high daylight levels, and offer highly controlled ventilation and good distribution of air. They are also very flexible, in that the location, number and size of roof windows is almost unlimited, and can provide an even distribution of daylight.