How to replace the sashes in the window

Intro

An essential part of maintaining timber windows involves replacing the sashes from time to time, which can be tricky if you’re not sure what you’re doing. Below you’ll find a step by step break down to help replace the sashes and complete any necessary repairs.

Steps

  1. Undo the knot on the cord on one side of the frame for the upper sash and re-fix to the upper sash.
  2. Undo the knot on the opposite side and fix to the opposite side of the sash.
  3. Place the upper sash back in the channel and test the movement up and down.
  4. Make any adjustments if not quite running smoothly or the cord is incorrectly positioned.
  5. Measure the frame and cut the parting bead to the correct size.
  6. If there is parting bead along the top, mitre the top corners at 45°.
  7. Measure from the top of the frame to the middle of the meeting rail on the top sash and cut the parting bead at this point.
  8. Fix the top half of the parting bead into the groove with the weatherpile facing the top sash.
  9. Fix the bottom half of the parting bead with the weatherpile facing the opposite way (this will then engage with the bottom sash).
  10. Repeat for the opposite side, making sure the draught proofing faces the correct way.
  11. Insert the parting bead at the top, if required, with the weatherpile facing the top sash.
  12. Test the movement and the seal of the top sash, and make any necessary adjustments at this point.
  13. It is sometimes a good idea to put a bead of painters caulk along the inside edge of the parting bead, where it meets frame and the top and bottom, to fill any gaps for a nice finish.
  14. This is a good opportunity to paint the parting bead with a top coat – taking care not to paint the weatherpile.
  15. Undo the knot on one side of the frame of the bottom sash and re-fix to the bottom sash.
  16. Undo the knot on the opposite side and fix to the opposite side of the sash.
  17. Place the lower sash back in the channel and test the movement up and down.
  18. Make any adjustments if not quite running smoothly or the cord is incorrectly positioned.
  19. Measure the height and width of the frame for the staff bead.
  20. Cut some new primed staff bead for the top and bottom, and both sides, making sure the corners are mitred.
  21. Place all 4 pieces of staff bead into the frame in the correct position, making sure there is the correct compression on the weatherpile.
  22. Starting on one side pin the staff bead near each end to fix into place. Do not put the pin all the way in – if adjustments need to be made, the pin can be removed.
  23. Repeat for the other 3 pieces of staff bead, making sure they are all aligned and neat.
  24. Test the movement and the seal of the bottom sash, and make any necessary adjustments.
  25. Once everything is in working order, fully hammer in the existing pins, and add pins at spaces every 6” or so along the bead to fully fix to the frame.
  26. A bead of painters caulk can be applied around the staff bead where it meets the frame to fill the gap, provide a neat finish and further enhance the draught proofing at this point.
  27. The staff bead can now be painted to finish off – taking care not to paint the weatherpile.