Double-glazed windows in Berwick & South East Melbourne.

The IGU build (the glass sandwich).

• Clear + Low-E + argon - the standard. 4mm clear outer + 12mm argon cavity + 4mm Low-E inner. U 1.6 W/m²K, SHGC 0.55. Suits north and east orientations.
• Tinted + Low-E + argon - for hot west-facing rooms. SHGC drops to 0.30-0.35 to block summer afternoon heat. ~$80-$120/window premium over clear.
• Laminated + Low-E + argon - safety glass (required for low-level glazing within 750mm of the floor and within 300mm of a door). Also a useful acoustic upgrade.
• Acoustic asymmetric build - 6mm float + 10.38mm laminated with optimised cavity. Rw 38-42 dB. For Mulgrave Fwy / Princes Hwy / Moorabbin flight path homes. ~$2K-$3K/window premium. See acoustic glazing.
• Triple-glazed - rare in SEM, only justified on extreme north-facing passive-house builds or homes targeting 8-9 star NatHERS. Adds ~$300-$500/window over double.

Frame options.

• Thermally-broken aluminium - the default for full-replacement jobs. A nylon thermal break in the frame section stops heat conducting through the aluminium. Whole-of-window U ~1.7-1.9. Powder-coated to any standard or custom colour. The growth-corridor / new-build default.
• Timber rebate IGU drop-in - keep your existing 80s or earlier timber sashes, we machine new beads and drop a 20mm IGU into the original rebate. Saves $400-$700/window. Best for heritage, Old Berwick, period homes where the sash is still beautiful.
• New timber frames - thermally-broken solid timber (Western Red Cedar, Accoya, or treated Vic ash). Premium look, period-appropriate, U ~1.6-1.7. ~$200-$400/window premium over aluminium.
• uPVC frames - rare in our market but available. Excellent thermal performance, lower price point, harder to repair than aluminium. Limited colour range.

Window operation styles.

• Awning - hinged at top, opens outward. Best ventilation in light rain. Standard kitchen / bathroom.
• Casement - hinged at side. Full opening, traditional look. Pairs with timber frames.
• Sliding - two-panel or three-panel. Standard 80s/90s replacement. Tighter seal in modern thermally-broken frames vs original mill-finish.
• Double-hung - vertical sliding, period-appropriate. Both sashes operable.
• Fixed / picture window - non-operable, largest IGU sizes possible. Best thermal performance (no operable seal to leak).
• Tilt-and-turn - European style, tilts inward at top for vent + opens fully for cleaning. Premium spec.

Pricing - installed.

Standard single window retrofit (up to 1.2m × 1.2m, argon clear Low-E, thermally-broken aluminium): $800-$1,500/window. Full-house retrofit (15-20 openings): $18K-$35K depending on frame type and any acoustic or laminated upgrades. VEU rebate of $3K-$6K typically offsets ~15-20% of full-house cost.