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Bottom Rail Replacement

Sometimes when the bottom rail of a sash window is in such a poor state that it cannot be repaired it can be replaced using the sash window repair method.

Below is just a very brief insight into our process of replacing the bottom rail. It is quite common for repairs to also be needed to the sash styles.

  1. The putty to the glazing rebate of the bottom rail and lower sections is removed. The ends of the sash styles are then cut and the hunching is removed along the same line of the mortise leaving what resembles a bridle joint and the bottom rail is removed. Any decayed timber is removed using our specially designed hand held router until sound timber is reached.
  2. The moisture content to the areas of the sash styles is checked ensuring it is below 18%. Any paint is removed to at least 10mm from the epoxy resin repair.
  3. A new bottom rail is cut with hunched tenon matching the thickness of the mortise leaving a 4mm gap at the shoulders for the epoxy resin (the bottom rail has already been pressure treated with preservative).
  4. The bottom rail is given 2 coats of wood primer ensuring the glazing rebate is sealed. Paint is stopped to a minimum of 10mm from the epoxy resin repair ensuring that the meeting surfaces of the existing timber and the new timber are left clean and dust free.
  5. The window care system's 2 part wood stabilizer is applied to all contact areas with a small brush. The Dry Fix is worked thoroughly into the surface and left for about 25-30 minutes the window care systems Dry Flex 16 epoxy resin is then applied to all areas of the sash window repair.
  6. Putty is applied along the glazing rebate to bed the inside face of the glass. A new bottom rail is inserted and secured checking the position of the new bottom rail ensuring an equal gap at the shoulders on either side. Resin is then applied to the mortise where the hunching once was and resin is also applied to the shoulders, removing any excess.
  7. At normal temperatures of about 20c, a drying time is needed of 16 - 18 hours before sanding and subsequent painting. At lower temperatures, we allow a longer period of time for Dry Flex 16 to dry. Once dry the areas of the sash window repair are sanded and wedges to the mortise and tenon are applied. Putty is applied to the glazing rebates of the lower section of sash styles and the bottom rail, in preparation for painting.