The most advanced double glazing system for existing timber windows

Name: Thermawood Otago
Address: 71 Maclaggan Street, Dunedin, Otago
Telephone: 03 488 4000
Price range: $$
Rating: 4.9

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Retrofit window double glazing Dunedin, Otago, Southland

Retrofit Double Glazing Specialists for Existing Timber Windows

Warmer, quieter and healthier homes without replacing your existing timber windows. Thermawood Otago is based in Dunedin and works throughout Otago, Central Otago and Southland.

If you have timber windows, you don't need to replace them to enjoy the benefits of modern double glazing. Thermawood Otago retrofits double glazing into your existing wooden windows and doors, retaining the character and natural insulating properties of the timber already in your home.

Using the NZ-designed patented Thermawood system, we upgrade your existing windows with modern double glazing while taking care of any timber restoration work needed as part of the process. It's a complete approach that allows you to keep the windows you already have while significantly reducing condensation and heat loss, cutting outside noise and improving comfort throughout your home.

Our customers regularly tell us how much warmer, drier and quieter their homes feel – and how pleased they are that they were able to keep their original timber windows.

Thinking about double glazing? Talk to Thermawood Otago before you replace your timber windows. We'll take a look at what you have, explain what's possible and provide a quote for upgrading your existing windows with the Thermawood retrofit double glazing system.

Our Services

The Thermawood System

The Thermawood System is a complete double glazing retrofit system designed to protect the timber and glass. Purpose-designed drainage and Warm Edge technology help deliver lasting thermal performance.

Retrofit double glazing

Double glazing wooden windows without replacing your existing timber joinery is a cost effective upgrade. Enjoy a warmer, much quieter home with less heat loss and condensation. We can retrofit double glazing into aluminium windows too.

Timber window restoration

Wooden window repairs and restoration prepare damaged or ageing windows for retrofit double glazing. Rot, draughts and operating issues can all be addressed as part of the upgrade.

heritage windows

Retrofit double glazing and restore heritage and villa wooden windows and doors including leadlighting without losing the character that makes them special.

condensation

Retrofit double glazing keeps the inside glass warmer, significantly reducing condensation on your windows. Less moisture on the glass helps create a warmer, drier home.

gallery

Browse our gallery to see completed retrofit double glazing, timber restoration and heritage window projects.

Our Partners

Physical Address
71 Maclaggan Street, Dunedin, Otago

Contact Number
03 488 4000

Hours Of Operation
Monday to Friday: 

8am - 5pm

Thermawood Otago provides expert retrofit double glazing solutions for homes throughout Dunedin, Otago, Central Otago and Southland. We upgrade your existing timber windows to improve warmth, comfort and energy efficiency, while retaining the character and craftsmanship of your home. Thinking about upgrading your windows? Get in touch, we’d be happy to talk through your options and what’s possible for your home.

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What Our Clients Say

"Brilliant service! The team (with James) went above and beyond. We had very old original 1930s windows, some with lead lights. These were restored and double glazed (and in one case, a completely new frame built) to a very high standard. The advice from the team was very much appreciated too. So pleased with our windows and looking forward to getting the rest of the house done."

Samara Tamati

"It has been over 2 years since we had our widows retrofitted and double glazed by Thermawood. From Daryl on down to James and his team of installers the process was smooth and straight forward. They were sensitive to our family needs and worked around our schedule. James and his team did an amazing job with the windows and we couldn't be happier. The new windows also eliminated all of the condensation that used to build up on the windows we had replaced. They have continued to perform well, and we have had no issues with the windows since their installation. Could not recommend them more!"

Jim Loehr

"Amazing product, fantastic service, and great guys to deal with. Over the years, we have slowly upgraded our wooden windows to double glazing. They still look beautiful, and the improvement in sound reduction and heat retention has been incredible. We’ve also had the windows replaced in my mother-in-law’s two-storey home, and they look stunning. The service has always been top-notch — consistent, friendly, and professional. Highly recommend."

Kat Reece

"I am happy to recommend Thermawood Otago to anyone wanting Double Glazing. From first contact through to having the Retro Double Glazing fitted was completed with professional service. The men that came to install the windows were great and I felt very comfortable with them in my home. Thankyou team. A lovely experience all round."

Marilyn Provis

Why Choose Thermawood Otago

The patented Thermawood system

Purpose-designed for existing timber windows, the Thermawood system combines modern double glazing with drainage and Warm Edge technology for lasting performance.

Double glazing + timber restoration

Retrofit double glazing and timber joinery expertise under one roof means any necessary repairs (including rot) and restoration work can be completed as part of your project.

A Great team to work with

Customers tell us our team is friendly and easy to have around, with great communication throughout the project. They appreciate the care we take, the attention to detail and the quality of our work.

Extensive heritage experience

From heritage homes to commercial buildings, we understand how to upgrade original timber windows, doors, sash windows and leadlights while preserving their character.