Single vs double glazing in cool-climate Hobart.

On the mainland, the glazing argument is often about keeping summer heat out. In Hobart it is the reverse: the long, cold winter means the priority is keeping hard-won warmth in. A single pane of glass is one of the weakest points in any home’s thermal envelope, and across a Hobart winter that single pane is working against you from May through September. That is why the case for double glazing is genuinely stronger here than in Brisbane or Sydney.

What single glazing costs you.

Single glass leaks heat fast, so the heater runs harder and longer. It also runs with condensation on cold mornings, particularly in waterfront and elevated suburbs like Sandy Bay and Bellerive, which pools on sills, marks paint and feeds mould over time. And it does little for noise. None of that makes single glazing useless, plenty of Hobart homes have it, but it explains why so many homeowners here eventually upgrade.

What double glazing gives back.

• Roughly half the heat loss through the glass, so the home holds warmth and the heater works less.
• Condensation gone from the glass itself, because the inner pane stays close to room temperature.
• Quieter rooms, useful on busier roads through Glenorchy and Moonah.
• Low-E option, a heat-reflective coating that suits Hobart’s heating-dominated climate.
• Heritage-friendly retrofits, slim units into existing sashes or secondary glazing where the frame must stay.

Does it pay off?

For comfort and condensation, the payback is immediate, you feel it the first cold morning. For pure energy cost, the payback period depends on how much you heat and how many windows you do, but Hobart’s long heating season shortens it considerably compared with warmer cities. Many owners stage the work, doing the coldest and most-used rooms first. For a sense of cost, a heritage timber-sash retrofit runs roughly $1,100 per window; the glass repair cost guide and the pricing page have the full numbers.