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Double Glazing System
for Existing Timber Frames

Thermawood is the most advanced double glazing system for existing timber framed windows.

Save yourself the major expense of fitting new windows and timber framing. With a Thermawood conversion, we only need to replace the glass. It’s a simple procedure that works with any type of window. You get all the benefits of double glazing, and the character of your home is maintained. Watch the video to find out how it works:

Thermawood benefits

We complete the retrofit on site. No need to board up windows – what comes out goes back in the same day.

100% NZ made, designed for local conditions – helps keep your house warm in winter and cool in summer.

Retains look and function of original windows, including double-hung sash windows and heritage windows with leadlights.

Used successfully in thousands of conversions.

Installation allows moisture to escape while excluding draughts and noise.

Cost-effective compared with alternatives, and you’ll save on heating and cooling costs.

Special glass options available for extra insulation (argon gas), safety, noise reduction and UV blocking (low E glass).

The result: a warmer, drier, quieter and healthier home.

Our retrofit double glazing warranty

'Pay by the room' double glazing offer

We can provide you with a “pay by the room” quote.

This allows us to complete the double glazing of your existing windows in stages, as and when you can afford it.

There is no need, or expectation, for all the work on your house to be completed at the same time in one job.

We can work at your home every few months or when you have the budget. We will start with south-facing windows, and continue from there at a pace that suits you.