Emergency egress windows - dimensions and positioning

An emergency egress window should – (a) have a clear opening that is not less than 0.33 m2 in area; and (b) have a clear opening that is at least 450 mm high and at least 450 mm wide. The lower edge of the window opening should be not less than 800 mm and not more than 1100 mm above the floor except in the case of a roof window where the lower edge of the window opening may be not less than 600 mm above the floor. For the purposes of this paragraph an emergency egress window should be taken to include a door which leads to an area (e.g. a balcony) from which a person could escape or be rescued. The minimum height to the lower edge of the opening should not apply to such a door.