Why Window Timber Rots
Window frames and sills are some of the most moisture-exposed timber in any home. They sit at the junction between glass, wall and exterior cladding — exactly where water pools, paint cracks, and drainage fails. In Bayside Melbourne, the combination of coastal air, higher rainfall and older housing stock makes the problem more common and more aggressive than almost anywhere else in Victoria.
The damage usually starts where paint has cracked or lifted, allowing moisture to penetrate the raw timber underneath. Once water gets in, the timber swells, dries, cracks further and begins to rot from the inside out. By the time it's visible from the outside, there's typically significant damage underneath the paint surface.
What I Repair
- Window sills — the most common failure point, especially on north and west-facing windows
- Window frames — vertical and horizontal members where paint splits at joints
- Architraves — the decorative surrounds that hide the gap between frame and wall
- Bottom rails — the lowest horizontal member, which cops pooling water directly
- Sash frames — the moving parts of double-hung and sash windows common in period homes
How I Fix It
Every repair starts with a proper assessment. I cut back to sound timber — no patch-overs, no filling over active rot. Damaged sections are replaced with H3 treated pine, which is specifically rated for above-ground exterior use with periodic wetting — the exact conditions window timber faces.
For areas where full replacement isn't practical, I use Parchem Builders Bog to fill voids and restore profiles after structural timber has been stabilised. This gives a hard, paintable surface that holds long-term.
Every repair is primed and sealed before I leave. If painting is out of scope, I'll leave it ready for your painter with clear instructions on what product to use and where.
The Moisture Source
Fixing the timber without addressing the moisture source is a short-term solution. I'll flag any drainage, caulking or flashing issues I find while I'm there — rot always comes back if the water pathway isn't closed off.
Service Area
I carry out window rot repairs across Moorabbin, Brighton, Sandringham, Cheltenham, Mentone, Bentleigh, Hampton, Beaumaris and surrounding suburbs. All within a 5km radius of Moorabbin.
Get a Quote
The fastest way to get a price is to send photos. Use the form below, attach a few shots from different angles, and I'll come back to you with an honest assessment — usually within a day or two.