Existing drainage features must not be obstructed by an ordinary repair. Show the complete threshold arrangement in the enquiry. Changes to a drainage or glazing system require the appropriate expertise and are not authorised simply because the damaged rail is nearby.
A replacement rail or insert needs the correct shape and dimensions. Provide the system reference where available. Similar-looking tracks may support different rollers, so a generic strip should not be assumed to be a suitable repair for every sliding door.
The agreed repair is checked with the accepted panel and its hardware. Catching at one point can differ from resistance along the entire run. Any roller or alignment work should be listed separately so a track-only quote does not imply every movement problem will disappear.
Repair an accepted accessible rail or fit a compatible running insert or replacement section without changing the building envelope. Scope limits: Accessible non-structural running rails only. No threshold waterproofing alterations, drainage-system redesign, structural changes, major glazing or powered operators.