Aluminium and PVC windows – loose or missing glazing seals

Cause

Weathering, UV light exposure

Repair

  • reinsert seals if in good condition using the handle end of a mid-sized screw driver

  • replacement seals are available from hardware suppliers or window frame manufacturers. Take a sample of the existing seal to ensure a correct profile and size match

  • remove old seals by starting at one corner and prising out a section of the seal. Once a section has lifted, the rest of the seal will generally easily pull out

  • cut a replacement seal longer than the size you want. When inserting new seals, length should be slightly oversized to give a tight fit

  • starting from the top centre of the frame, push the seal into the gap between the gasket groove or bead and the glass. Spraying soapy water on the seal can help installation

  • work the seal into the gap all the way around the perimeter of the frame. Take care to ensure that that the seal is properly fitted into the corners of the frame

  • do not stretch the seal as it is being inserted. If a seal is stretched during installation it will eventually retract, leaving a gap where the two ends of the seal meet

Cause

Incorrect length/size of glazing seal 

Repair

  • remove and replace seals as described above

Cause

Glazing seals were stretched during installation

Repair

  • remove and replace seals as described above. When inserting new seals, length should be oversized to give a tight fit