Can You Double-Glaze Heritage Sash Windows in Melbourne?

Q: Will my windows look different?

Done properly, visual change is minimal. We match beads and keep profiles consistent to preserve appearance.

Q: Can every sash be double-glazed?

Not always—some sashes need reinforcement or like-for-like replication to carry the additional glass weight safely.

Barnsbury Joinery
Oct 15
2 min read

Updated: 6 days ago

Many Melbourne homeowners want better comfort without losing period character. The good news: slimline double glazing can often be integrated into timber sash windows — but success depends on profiles, weights and heritage context.

What “slimline” double-glaze heritage sash windows really means

Narrow cavity insulated glass units (IGUs) designed to fit traditional sash rebates
Profile-matched beads preserve sight-lines
Discreet seals for weathering and acoustic gains

Benefits you can feel with double-glaze heritage sash windows in Melbourne

Winter warmth / summer cool with reduced drafts
Quieter rooms facing tram routes and main roads
Lower condensation when paired with proper ventilation

What makes a sash “suitable”?

Sufficient rebate depth and overall sash strength
Counterweights re-balanced for heavier glass
Sound frames and rails (decay addressed first)If an existing sash can’t safely carry the unit, a like-for-like replica sash may be recommended.

Heritage and approvals

Like-for-like repairs are often exempt. Changes to glazing specification may require permission in some overlays or precincts. Always check with your council before proceeding; we’ll advise the likely route for your address to install double-glaze heritage sash windows in Melbourne.