Repair or Replace? Rotten Timber Windows in a Heritage Home

How much rot is too much?

Rot in heritage windows usually concentrates at the sill, lower rail, and joints where water collects, while the bulk of the timber remains sound. In most cases only part of the element is affected, and a Dutchman splice, cutting out the decay and letting in matched timber, restores full strength invisibly. Replacement is only justified when decay is so extensive that little original fabric remains.

Why repair usually wins

• Original old-growth timber is more durable than modern replacements.
• Repair retains the character, proportions, and value of the home.
• On heritage-listed properties, retaining original windows is often required.
• Fixing the moisture cause means the repair lasts, rather than recurring.

The key is to act before rot spreads and to fix the underlying moisture problem at the same time. If you are unsure whether your windows can be saved, an assessment will give you a clear answer.