Loft Conversions
- The building regulations
Chris Wigley
MD London Building Control Ltd
www.londonbuildingcontrol.co.uk
Scheme 1: Bungalow with Loft
Conversion
Scheme 1: Bungalow with Loft
Conversion
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Option 1A: Means of escape from first floor
windows
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Means of escape windows to all first floor habitable rooms
(minimum 450mm wide, with opening of 0.33m2)
Interlinked mains SD to halls/landings
Option 1B: Protected route
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with enclosed staircase leading to final exit
FD20 doorsets to habitable rooms including kitchens and
rooms with boilers
Interlinked mains SD to halls/landings
Scheme 2: Two Storey house with
Loft Conversion
Scheme 2: Two Storey house with
Loft Conversion
Scheme 2: Two Storey house with
Loft Conversion
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Option 2A: A protected route
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Two Storey house with Loft Conversion (Lounge open to
stairs)
As Option 2A: Re-instate a protected route
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with enclosed staircase leading to final exit
FD20 doorsets to habitable rooms including kitchens and rooms with boilers
Interlinked mains SD to halls/landings
Form route using 30 minute FR construction (FD20 doorsets) or fire-curtains
Option 2B: Sprinklers
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Sprinklers to Ground Floor rooms
FD20 doorsets/construction to separate the Ground Floor from the First Floor
MOE from a First Floor room to a place of safety
First Floor doors to be FD20 or upgraded using envirograf or similar
New doors to the loft to be FD20
Scheme 3: Three Storey house with
Loft Conversion
Scheme 3: Three Storey house with
Loft Conversion
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Option 3A:
Protected route and smoke
detection throughout
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Protected route to final exit
FD20 doorsets throughout
SD throughout (HD in kitchen)
No open plan arrangements allowed
Scheme 4: Two Storey building
(flats) with Loft Conversion
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Option 4A: Independent access
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Treat as Two Storey house with Loft Conversion (Scheme A)
Option 4B: Creation of maisonette
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Protected internal stairs to a flat exit
FD20 doorsets throughout
SD throughout (HD in kitchen)
Scheme 5: Three Storey building
(flats) with Loft Conversion
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Option 5A: Independent access
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Treat as Three Storey house with Loft Conversion (Scheme
C)
Option 5B: Creation of maisonette at a high level
(over 7.5m above Ground Level)
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Protected internal stairs to a flat exit
SD & FD20 doorsets throughout
Secondary escape route/stairs required, or a fire engineered
solution
Guidance based upon LABC
Technical Guidance Note
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This guidance is intended for two storey houses that are
converted to form 3 storeys.
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The new 3rd storey floor area should not exceed 50m².
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Existing hardboard or other lightweight (hollow-core)
doors are not considered adequate to provide a
reasonable level of fire protection to a stair enclosure
and should therefore be replaced with FD 20 doors.
Option 1: Upgrading existing doors
(minimum 32mm thick)
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Detection throughout: smoke detectors should be provided in all
habitable rooms, at every storey level (including any half landing levels
adjacent to habitable rooms) with a HD in the kitchen. All alarms should
be mains powered with battery backup, and interlinked. BS 5839:6
recommends optical detectors in circulation areas with ionization
detectors for living/dining rooms. Either type is acceptable in bedrooms.
There should be at least one window at first floor level of a size that
would permit emergency egress to either a rear garden of sufficient depth
(i.e. at least as deep as the rear elevation’s height) or from the front elevation,
leading to a place of safety (i.e. not over light wells)
The door should be attached to the door frame with steel hinges, not be
visibly warped, fit well into its frame and there should be no visible
defects particularly in the panels.
Any existing glazing to doors or fanlights should be replaced by wired
glass or similar fire resistant glazing to provide adequate resistance for
integrity and stability.
There should be no significant defects to adjacent walls or around door frames forming the stair enclosure.
Option 2: Upgrading existing doors
(less than 32mm thick)
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Detection throughout: smoke detectors should be provided in all habitable rooms, at every
storey level (including any half landing levels adjacent to habitable rooms) with a HD in the
kitchen. All alarms should be mains powered with battery backup, and interlinked. BS 5839:6
recommends optical detectors in circulation areas with ionization detectors for living/dining
rooms. Either type is acceptable in bedrooms.
There should be at least one window at first floor level of a size that would permit
emergency egress to either a rear garden of sufficient depth (i.e. at least as deep as the rear
elevation’s height) or from the front elevation, leading to a place of safety (i.e. not over light wells)
The door should be attached to the door frame with steel hinges, not be visibly warped, fit
well into its frame and there should be no visible defects particularly in the panels.
Any existing glazing to doors or fanlights should be replaced by wired glass or similar fire
resistant glazing to provide adequate resistance for integrity and stability.
There should be no significant defects to adjacent walls or around door frames forming the
stair enclosure.
A proprietary solution should be sought to upgrade the door; this may include the
application of fire resistant materials to the panels and stiles on the room side of the door.
Such doors can be provided with a certificate from a specialist supplier confirming their
upgraded suitability.
Alternatively the door can be upgraded, on the room side, by infilling the panel with a fire
resistant board and applying a similar board glued and screwed over the entire door.
General Notes for all Options
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G1). Smoke Detectors can use a wireless link (if certification is provided).
G2). FD20 doorsets (not FD30 doors) are usually required in Loft Conversions;
smoke seals are not required. Intumescent strips are also not usually required as fire
doors are manufactured to provide 20 minutes FR without these strips -intumescent
strips are used to increase FR to 30 minutes, when this is required. 50mm thick
doorstops are also not usually required within dwellings as it is now accepted practice
to allow smoke to seep out and set off the detectors in the halls/landings.
G3). In a house, the top floor may have an open plan arrangement (ie. no door onto
the stairs). However this is not permitted in maisonettes (where an inner protected hall
is needed).
G4). Each scheme will need an individual survey to ensure there are no unusual site
conditions.
G5). Steels supporting floors/walls will need 30 minutes FR. Protection from the
underside is sufficient; the plasterboard needs to be at least 12.5mm thick fireline
board or similar – otherwise steels can be painted with intumescent paint.
G6). Where an older house/flat has low headroom, the new Loft Room floor may be
under 4.5m above the adjacent Ground Level. The provision then is only for SD’s in
halls/landings and an adequate MOE window from each new habitable room.
Thank you from
London Building Control
….. a new approach to Building Control
www.londonbuildingcontrol.co.uk