Double Glazing

Retro fitting double glazing is as simple as calling us on 0800 230 330. We can retrofit both aluminium and wooden windows in almost any style and size. We use a variety of customised solutions that incorporate property stash and beading systems to replace your existing single glazed windows with new double glazed insulated units, and when the job is finished; the results look fantastic.

Benefits of double glazing

  • Lower energy consumption

    It costs money to heat your home in winter and cool it in summer. Up to 31% of this energy is lost through your windows immediately. Double glazing can prevent 73% of this energy from being wasted and will save you a tremendous amount of money. The savings occur across all seasons as double glazing keeps your home cool in summer and warm in winter.

  • Less noise

    Double glazing provides an insulation barrier that can help reduce noise by up to 70%. Our customers who live on a busy street or in a windy location are constantly amazed at how double glazing has restored some peace and tranquility to their home.

  • Less condensation

    Double glazing prevents condensation forming on the inside of your windows creating a warmer, dryer, and healthier home.

  • UV protection and privacy

    Upgrading your home to double glazing? Now is the ideal time to consider adding UV filtering glass and protect your valuable furniture and furnishings from UV damage. Alternatively, you can install tinted or privacy glass and make a statement about your home while increasing your privacy.

  • Security and safety

    All retro fitted double glazed units are built to meet modern building standards. Double glazing is safer and stronger which means fewer breakages and fewer accidents.

How retro fit double glazing works

Retro fit double glazing is a process in which a single glazed window has the existing single pane of glass removed and replaced with a double glazed unit (an insulated glazing unit, or "IUG"). The combination of glass types used, the thickness of the glass, the spacer, and type of gas used to filled the space cavity all determine the insulation and the visual qualities of the IUG.

Pay back on double glazing

Double glazing used to be a luxury in New Zealand until recently when changes to the building act required most new homes to be built with double glazed windows. These days, double glazing is a common feature in new homes and buildings as potential buyers of older properties are aware of the benefits of double glazing and are placing higher value on these benefits.

Our customers tell us that when they look at purchasing or selling a home, double glazing is now a feature that helps decide the sell price of the property just as much as the number of bedrooms or whether it has a heat pump or not. Property valuers tell us that approximately 90% of the cost of retro fitting double glazing will be recovered at a time a home is sold.

Given the immediate financial savings through the reduction of energy bills and the immediate benefits of improved comfort and warmth; the payback on double glazing is more than impressive.

The steps involved

  1. Measure the windows on site.
  2. Discuss options and specify glass types.
  3. Remove existing glass.
  4. Replace with double glazed units.
  5. Fit new aluminium beading.
  6. Replace existing sashes with new, stronger ones.
  7. Replace existing handles, hinges, and stays.
  8. Clean the windows.
  9. Relax in your warmer, more comfortable double glazed home.


The best measure of how our services and products can enhance your life is what our customers tell us.

About our products

  • "The improvement in warmth is amazing."
  • "It's the reduction in noise that surprised us the most, we never realized how noisy the wind was."
  • "Not waking up to pools of condensation makes our home so much healthier and keeps our house clean and dry."

About our services

  • "The impressive and friendly staff left a good impression."
  • "We whole-heartidly recommend New Zealand Glass as a good, knowledgeable firm and would not hesitate to deal with them in the future."
  • "Fast and efficient, they know what they are doing and could offer us real, sensible advice."
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