Windows – reveals water damaged

Causes

Condensation

Aluminium window frames with no condensation channels, or condensation channels have no drainage 

Use of untreated timber or MDF window reveals

Leakage around window

Listed under: Interior, timber and wood-based, timber, windows, moisture, condensation

Cause

Condensation

Repair

  • reduce internal moisture levels. Don’t use unflued gas heaters or dry clothes inside. Vent clothes dryers to the outside or use a condensing dryer. Install a kitchen rangehood and bathroom exhaust fan and vent the steam to the outside. (If already installed, ensure they are operated when steam is being generated). Open windows fully for ten minutes each day if possible

  • where there are condensation channels and drainage holes in aluminium window frames, keep them clean and free of dirt with a soft brush

  • remove condensation from windows and sills whenever possible

  • allow timber to dry thoroughly before recoating. Keep reveals well maintained to minimise the effects of the occasional presence of moisture

  • where reveals are damaged beyond just the appearance, remove rotted timber, treat exposed edges with preservative, fill with a sandable filler and paint. Where damage is significant, remove existing reveal and replace – this will require the window to be removed

Back to top

Cause

Aluminium window frames with no condensation channels, or condensation channels have no drainage 

Repair

  • reduce internal moisture levels as in the repair above
  • consult with a window installer/maintenance contractor about whether it is possible to drill drainage holes in the frame to allow water to drain outside. If it is possible, ensure drainage holes are kept clear
  • remove condensation from windows and sills whenever possible
  • keep reveals well maintained and coated (paint or clear finish) to minimise the effects of the occasional presence of moisture

Back to top

Cause

Use of untreated timber or MDF window reveals

Repair

  • see drawing
  • reduce internal moisture levels as in the first repair above
  • where damage is beyond just the appearance, replace reveals or sections of timber reveals. Remove rot-affected timber and treat cut ends of timber with preservative. Seal all faces of new sections and glue new sections of reveal with waterproof adhesive. Replacing the whole reveal may require that the window is taken out
  • replacement reveals, including for damaged MDF reveals, should be radiata pine H3.1-treated, treated rimu, cedar or cypress (A heart). Repaired areas may require painting

Back to top

Cause

Leakage around window

Repair

  • identify and remedy the source of water entry. If you cannot find the source of entry, or multiple windows have the same problem, consult a registered building surveyor for advice
  • for small areas, remove rotted timber, treat exposed edges with preservative, fill with a sandable filler and paint
  • for significant damage, remove existing reveal and replace – this will likely require the window to be removed

Back to top