Painting techniques: Using primers and other sealers effectively

Unsure of what primer is or how to use it or what kind of undercoat to go for? Use our guide to paint your way to perfection.


  • Paint onto resinous areas, especially knots, in wood.
  • Prevents resin in wood from seeping out and discolouring paint.
  • When dry, coat knotting with primer.

Read more painting techniques: How much paint should I buy? 



  • Apply to new or bare wood, plaster or metal.
  • Seals pores in absorbent surfaces and forms a key to which other coats grip.
  • Buy primer for a specific surface or use all-purpose primer.
  • Prime bare plaster with proprietary sealer or a coat of emulsion diluted to one part water and four parts paint.

Read more painting techniques: Which painting tool should I use—brush, roller, pad or spray gun?



  • For stained walls and plaster, old bituminous coatings and areas treated with preservative.
  • Contains fine scales of aluminium and forms a barrier to seal the surface.
  • Apply a second coat if stain is still visible after the first has dried.

Read more painting techniques: Preparing to paint difficult surfaces


Stabilising Solution

  • Sometimes used to seal distemper.
  • Binds together surfaces to provide a firm support for paint.
  • Apply fungicide before stabilising solution on a mould-affected surface.



  • Kills mould on any affected surface.
  • When spores are dead, brush them away and apply another coat.

For more stories, tips and laughs like us on Facebook or follow us on Twitter

For more DIY tips click here

If you found this article useful, share it!