DIY summer tip

As a general rule, it pays to seal natural stone tiles before you lay them, certainly before you grout them because the adhesive and grout will be hard to clean off if the tiles have an uneven surface.

Use a tile-sealer liquid (try QEP Tile Sealer, £12.98, B&Q), following the manufacturer’s instructions.

If you’re sealing riven slate (or something similar), which has a ‘grain’, apply the sealer in the direction of the grain.

Using too much sealer can leave white marks, so be careful not to, but if you have applied the sealer with the grain, the marks will be less noticeable and you may not need to remove the sealer and start again.