a) The extension has a completely transparent or translucent roof.
b) The extension walls are substantially glazed. (Should not have more than 25 % of its wall area as brick work)
c) The extension has a floor area not exceeding 30m squared.
d) The extension is sited at ground level.
e) The extension is permanently separated from the remainder of the property by means of a door.
f) Any radiator within the conservatory is controllable. (If fixed heating installations are proposed, they should have their own separate temperature and on/off controls).
g) The glazing satisfies the requirements of part N, Schedule 1 (toughened/safety glass).
h) The extension does not contain any drainage facilities. (i.e. sink, WC, or washing machine)
An example of where building regulation approval may be required is a Kitchen / Conservatory Extension. We suggest you contact your local council – explain your intentions – they will be able to give you more specific advice.
As a further guide conservatories that require building regulation approval will need glazing of the highest insulation quality i.e. – Pilkington K Glass (low E) with argon filled units.