Sanding and repainting wooden windows

Loosen flaking paint and stain with a scraper, then sand off everything loose with P80. Old paint that is still firmly bonded can stay – it just gets keyed. Grey, weathered wood has to go until fresh, pale timber appears: no paint will hold on the grey layer.

Frames and casements have lots of profiles, rebates and narrow beads that no backing pad can reach. Work there with sanding strips on a hand block, folded paper or non-woven abrasive. Protect the glass with masking tape – sandpaper scratches glass.

Finally, key the whole surface evenly with P180, remove the dust and prime any bare spots. Between primer and top coat, sand lightly with P240. Work in dry weather: damp wood makes the paint flake off later.

The bottom rail and the weatherboard take the most rain. Test with a screwdriver: where it goes in easily, the wood is rotten. Chisel these spots out back to sound wood, fill with wood repair compound and, once cured, sand flush with P120 and P180.

Remove rubber seals or mask them carefully – painted-over seals go hard and stop sealing. Renew cracked putty or silicone around the glass before painting; over old joints the new paint cracks again straight away.