Window :
1.External windowsills shall be set weathered, and project beyond the external wall face.
Internal sills shall be made of tiles or similar material to suit the type of room concerned. To
prevent accumulation of dirt, these internal sills shall be set sloping inwards in control buildings, wash and locker rooms, and toilets.
2. All exterior windows in heated and/or air-conditioned buildings shall be designed with weather-stripping (sealing) as described for doors."