Moisture prevention measures
The sill is usually made from a dense weather-resistant timber, with a sloping rebate to shed water. A drip groove on the underside stops water from running back in under the sill.
![A diagram showing the cross-section of a sill. A drip groove underneath the sill on the outside stops water running back in on the underside of the sill.](images/page_002_sill.jpg)
Cross-section of a sill
![A diagram showing how flashing is placed around a frame. The flashing is folded down, then the ends are folded up the jambs, and then the inside corners are folded around on to the sides of the frame.](images/page_002_sill_flashing.jpg)
This diagram shows how flashing is placed around the frame
![A diagram showing a door frame set into a wall. The frame is fixed to the jamb stud that has already been packed. Packing is placed behind where the lock striker will be located.](images/page_002_door_frame.jpg)
This diagram shows a door frame set into a wall