Most conservatories do not fall under the jurisdiction of the building regulations and a building regulations application will not be required if the conservatory meets the following conditions:
Is built at ground level and is less than 30 metres square in floor area.
At least 50% of the new wall and 75% of the roof is either glazed or made of a translucent material.
The conservatory is separated from the main house by an external door(s). This does not include internal quality doors.
Glazing in terms of safety glazing and any fixed electrical installations to comply with Part P of the building regulations.
Conservatories Below Escape Windows
You are advised not to construct conservatories where they will restrict escape access from the first floor or second-floor escape windows. If a conservatory is to be put below one of these windows a polycarbonate type access roof is recommended so that in the event of a fire a person can walk across the roof and escape. Always ask your conservatory supplier about the roof below escape windows and ensure this has been taken into account.