Vacuum the loose debris out first, then wet the rest. Doing it the other way round turns dust into a paste that is far harder to remove.
The method
- Dry vacuum first. Use a crevice tool along the full length of the track and into both corners. Removing the loose material dry is what makes the rest easy.
- Loosen the compacted layer. A stiff brush, an old toothbrush or a dry paintbrush breaks up what the vacuum could not lift.
- Vacuum again. Repeating this step is what separates a good result from a mediocre one.
- Apply a cleaning solution. Equal parts white vinegar and warm water in a spray bottle. Let it sit five minutes on stubborn areas.
- Scrub and lift. Work along the track with the brush, then absorb the dirty liquid with paper towels rather than pushing it around.
- Detail the corners. Cotton buds, or a flathead screwdriver wrapped in a cloth, for the ends where the track meets the frame.
- Dry completely. Standing water in a track invites mould and, on metal frames, corrosion.
The weep holes matter more than the dirt
Along the outer edge of most sliding window tracks are small slots or holes. These drain rainwater that gets past the seal back to the outside. When they clog with the same debris that fills the track, water has nowhere to go. It pools, then backs up over the inner lip of the frame and into the wall cavity.
Clear them with a thin wire or a cotton bud, then test by pouring a little water into the track and watching it drain. This single check prevents a class of damp problem that people usually blame on the window seal.
For tracks that have been left for years
Where the deposit has set hard, sprinkle bicarbonate of soda along the track and spray white vinegar over it. The reaction lifts compacted grime mechanically as it foams. Give it ten minutes, then scrub and vacuum. On very bad tracks this may need two passes, but it avoids scraping, which scratches aluminium and vinyl frames.
Keeping them clean
- Vacuum the tracks whenever you clean the windows. Two minutes prevents the compacted layer forming at all.
- Check the weep holes twice a year, before winter and after spring.
- Do not lubricate with oil-based sprays. They attract dust and create the paste faster. A dry silicone lubricant is the correct choice for sticking sliders.