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Repair timber sliding door

If not regularly maintained or painted, timber becomes dry and brittle and breaks easily. In this feature we show you have to fix damage to a timber sliding door.


When you paint exterior wood it tends to become brittle and dry over time. When it's brittle, it damages easily, but thankfully it can be repaired and save you the expense of buying a brand new door.

Wooden doors and window frames that have been painted over or not regularly maintained are susceptible to damage, particularly along the edges. On a sliding door, the bottom edge of the door can split or break away. Since the roller assemblies are mounted in the bottom of the door, the door can eventually come off the track. It's important to tend to any damage immediately - before moisture gets into the timber.


Wood glue, exterior grade

Wood filler, exterior grade


Primer and paint to touch up, suitable for exterior wood

Sander plus assorted sanding pads

Hammer and panel pins






GOOD TO KNOW: Where pieces have broken off, keep these in a safe place until you get round to doing this project. If the pieces are lost, you will need to build new pieces to fill the gaps using a wood epoxy putty such as Alcolin QuikWood, or cut a new piece of timber to fit.

1. Remove the door from the track assembly and place on a couple of saw horses or work benches so that you can remove any roller assembly, or work around a fitted track.

2. Clean out the damaged area to remove as much loose debris as possible, as this will interfere with the joining.

3. Apply exterior-grade wood glue to the damaged area and press the broken piece back in place.

4. Clamp the piece in place and hold firmly with a clamp. If you need to add a few panel pins to hold the pieces together, predrill pilot holes to prevent splitting the timber.

5. Use exterior-grade filler (for timber) to fill gaps between the patched pieces. Larger gaps can be filled with Alcolin QuikWood. Only apply enough filler to cover the damage area, and avoid the area where the roller assembly will be re-fitted. Leave to dry for the specified amount of time.

6. Once dry, sand the repaired area smooth with an orbital sander.

7. Apply primer and paint to match the existing finish.

8. Fit the roller assembly. It is difficult to source roller assemblies for sliding doors, so you may need to re-fit the old one. Before you do, give it a good clean with an old toothbrush and WD-40 before fitting. Check the height before re-fitting the door onto the sliding track assembly.

GOOD TO KNOW: To find a bottom roller for your particular sliding door, get in touch with to find your nearest retail outlet.