Which Wood Preservative for painted Timber Windows with rot? No Rot Gel.

wood preservative | window repair

One common question asked by the public is how to conduct a window repair when its affected by wood decay. The next question always is, what’s a suitable wood preservative when the window repair is to be painted over. The answer is quite simply: No Rot Gel.

Preschem No Rot Gel Wood Preservative

The cause of the wood decay, or dry rot is typically due to the paint system starting to break down by cracking or peeling. This allows moisture to get into the timber when it rains thus allowing the onset of timber decay. To remedy this it is recommended that you apply a suitable wood preservative such as Preschem’s No Rot Gel:

  • Strip or sand back the painted surface to bare timber around the affected section, preferably 300mm in all directions from where there is visible decay.This is advisable even if the rot is localised in one small section, as the fungi will be spreading via tendril like fingers that will be difficult to detect under the painted surface. The fungi will do this to spread elsewhere if the conditions are right. It’s best to knock it properly on the head the first time rather than have it causing you grief several years down the track, including the potential of having to replace the window frame entirely.
  • Dig out the dry rot carefully with a chisel or similar implement until you get to sound wood.
  • Dampen the timber with water
  • Apply No Rot Gel timber preservative as per the directions on the pack. Ensure that 2 coats are applied within 2 hours. If you leave it longer than that between the recommended two coats, you run the risk of the solvent drying, which means the second coat will not soak in. You can apply the second coat as soon as the first one has soaked in.
  • Allow the No Rot Gel to dry for about 24 hours
  • Use a suitable exterior timber filler to repair the cavity. Allow it to dry as per the manufacturers recommendations, then sand to a smooth uniform surface.
  • Paint over the repair with a quality exterior paint.

The advantage of No Rot Gel being used in this way is that it will kill and sanitise any dormant or active wood rot including the tendrils that are looking for another spot to grow. In addition, the timber preservative is locked in under the paint, where the boron active ingredient will remain there indefinitely, waiting for such a time where moisture starts finding its way back into the timber. Obviously if you’re properly maintaining your painting, then this could be a very long time indeed, as dry wood won’t rot.

Note: If you’re wanting a timber treatment for exterior use that won’t be painted over, then Timber Preserver is product to use.

For those of you who live within the Melbourne metro region and wish to have a tradesman come and do the work for you, then I recommend that you contact the Wood Rot Doctor to discuss your repair requirements on 1800 641 711 or visit the website at woodrotdoctor.com.au