Conservatories And Porches
All conservatories and porches are exempt from the regulations provided they satisfy all of the following:
- they are built at ground level,
- they are single storey,
- they have a floor area less than 30m², and
- the glazing complies with Part N of the regulations (i.e. protection against impact).
The Building Regulation definition of a "conservatory" is:
"A single storey part of a building at ground floor level, where the roof and walls are substantially glazed with a translucent or transparent material, intended for growing plants, but often used as occasional living space. A conservatory has not less than three-quarters of the area of its roof and not less than one-half of its external walls made of translucent material."
The definition of a "porch" is:
"A single storey extension, used primarily as a wind shelter, but also used for the storage of coats, shoes, umbrellas, and the like, attached to an existing building at ground level and fixed over an access door."
Part N 
requires glazing with which people are likely to come into contact whilst moving in or about the building should break safely, if it breaks, or be robust in small panes, or be permanently protected.
Conservatories and porches must be separated from the habitable parts of the building by suitable windows, doors or walls.
NOTE: The Government is currently reviewing the above exemptions. A recent consultation paper indicates that the current exemptions on size are likely to be significantly reduced.
Health and Safety
You must ensure that the erection of the conservatory or porch will not cause danger to health and safety. You should ensure that your proposal will not affect:
- flues from appliances,
- any ventilation openings which serve any appliance,
- ventilation openings to rooms, and
- any existing means of escape in case of fire routes.
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