The new floor elements must have adequate support and should be sized and spaced according to the spans involved.

This new element of const
The walls
The new floor must be supported by load bearing walls adequate to carry the new loads and must have a suitable foundation. A full structural appraisal by an appropriately qualified professional is therefore recommended.

Fire resistance of the walls, both new and existing, is again of major importance and expert advice will again be needed.

Depending on the layout, the new doors will have to be fire doors or in some cases existing doors ‘fitted with’ self-closing devices.

Generally any existing glazing contained in the walls of the stairway enclosure must be replaced by fire resistant glass.

In the case of the walls to a dormer window it will be necessary to ensure they are suitably weatherproofed and insulated. If the dormer is close to an adjoining property it will be necessary to provide additional fire protection to this element from both inside and outside.

The stairs
The preferred access to the new room should be via a traditional straight flight of stairs with landing top and bottom. Spiral staircases, fixed ladders and alternating tread stairs are considered in special circumstances, however only where there is insufficient space to accommodate a standard stair.

Suitable guarding and handrails must be provided to the stairs and adequate headroom maintained, usually measured at 2m vertically above the flight.

Escape in case of fire
The principal route of escape is provided by the staircase, which must discharge to a suitable final exit, normally a front or rear door.

The new room(s) should, where the new and existing staircases are not fully enclosed with fire doors to all rooms, have an openable window or roof light provided for escape and rescue purposes.

This window should be readily accessible, large enough to escape through and close enough to eaves level to aid rescue from an external source.

A dditional fire precautions apply if the loft conversion exceeds 50m² in floor area or the new second storey contains more than two habitable rooms.