Replacing Box Sash Windows
What material is best?
Your choice is between Plastic and Timber.
Plastic is sensitive to ultraviolet in sunlight, and will therefore discolour over time.
Plastic is difficult to renovate or revive.
Timber will require maintenance but, if done properly, will last indefinitely.
Timber, what is my choice there?
You can choose between Softwood and Hardwood.
Softwood requires preservative treatment before it is used. Because more and more ingredients are banned for
ecological and safety reasons, preservatives are becoming less effective.
Hardwood has the advantage of containing natural tannin and other natural preservatives, which make the timber
naturally long lasting and weather resistant.
Which is the best finish for exposed timber surfaces?
You have quiet a choice of both stains and paints.
The protection offered by stains is proportional to the presence of colour in them. The darker the stain, the better
the protection. Light stains offer little protection, and are not recommended for the outside surfaces of a window.
Paints, which can be either Gloss or Acrylic, are available in a range of colours.
Gloss paints are spirit based and do not penetrate the timber; which leads to eventual flaking.
Acrylic or micro-porous paints are water based and penetrate the timber. They allow the timber to breathe;
which eliminates flaking and makes the timber far more weather resistant.
How do I maintain my windows?
Plastic windows will discolour, and there is very little to be done about it; neither before, nor during or after.
With painting every five to seven years timber windows will be maintained.
Gloss painted timber windows require complete removal of previous coats, back to bare wood, before
repainting with primer, undercoat and two topcoats.
Special care should be taken to prevent build-up in corners to make sure there is no interference with
movement of the sashes.
Acrylic or micro-porous painted timber require a wipe over to clean, and one coat of paint,
making maintenance very simple.
