How to fit a sash stop for ventilation


It’s important to select the correct ventilation product and whether it needs to be lockable or suitable for fire egress. Follow our instructions on installing ventilation onto sash windows.


  1. Firstly, check whether the lower sash has horns protruding up from the meeting rail. If so, make sure there is enough room on the horn for the stop to engage onto.
  2. Mark the top sash, midway along the side stile, no more than 100mm up from the meeting rail on both sides. This will be the point the sash will stop (guidelines say no more than 100mm, though you may wish to make smaller).
  3. Refer to the individual fitting instructions of the sash stop for specific methods on hole sizes etc.
  4. Once the sash stop is fixed on both sides, test the operation by lifting the lower sash up to the stop point.
  5. Double check that the gap in the window does not exceed 100mm.