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.

Planning the details room by room? Read how to choose opening styles for each room, how to plan blinds, fly screens and handle clearance and how to keep windows matching across a staged project.

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.