Clarification on Double Glazing Windows and the building code.

Forums › Home Workshop DIY › Clarification on Double Glazing Windows and the building code.

jimbob79

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#214846 31-May-2017 10:19

I was chatting to a mate of mine who is an business, home & content insurance broker and he is say that all new properties being built needs to have double glazing windows as part of the building code. I asked "Does that apply to existing homes that are having alterations?", and that's where thinks got a bit grey and we were not quite sure.

Does anybody actually know the revised building code.

sbiddle

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#1792196 31-May-2017 10:28

Double glazing is not, and never has been a legal requirement to meet the building code.

A property needs to meet certain energy efficiency guidelines and figures which are different across the country. One way to meet those requirements is to install double glazing and in all honestly if you are building a new house you'd have to be pretty crazy not to install double glazed windows.

eph

187 posts

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#1792197 31-May-2017 10:28

Sorry I don't but just out of curiosity if you were adding/replacing windows why would you ever consider going single glazing??

jimbob79

673 posts

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#1792202 31-May-2017 10:42

eph:

Sorry I don't but just out of curiosity if you were adding/replacing windows why would you ever consider going single glazing??

There are some purest who are renovating old turn of the century (1900) houses who are keeping the 'colonial look' who are refuting to adhere to current building materials... i.e. Double Glazing.

I grew up with double glazing in the UK and I also think it's crazy not to have anything less myself. In fact it was a hard push to convince my kiwi wife to have double glazing because she knew no better.

About 7 years back I was talking to a builder who was so 'long in the tooth' and naive that he thought that UPVc Windows was the work of the devil. That was a very painful conversation.

tdgeek

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#1792211 31-May-2017 10:48

jimbob79:

eph:

Sorry I don't but just out of curiosity if you were adding/replacing windows why would you ever consider going single glazing??

There are some purest who are renovating old turn of the century (1900) houses who are keeping the 'colonial look' who are refuting to adhere to current building materials... i.e. Double Glazing.

I grew up with double glazing in the UK and I also think it's crazy not to have anything less myself. In fact it was a hard push to convince my kiwi wife to have double glazing because she knew no better.

About 7 years back I was talking to a builder who was so 'long in the tooth' and naive that he thought that UPVc Windows was the work of the devil. That was a very painful conversation.

I had double glazed put into an older character home. Same window sizes, white, but I got the cross option ( a "plus" shaped cross) in the non large windows, and yes, while it isn't original ,the sizes were and it looked great. Shale blue roof, white walls, white windows, very tidy and clean look

eph

187 posts

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#1792224 31-May-2017 11:17

Haha. We've just had our ones replaced with European style uPVC windows and they are great feels a bit more like a proper house now :).

I guess for the old houses you can always consider retrofit double glazing into existing frames but you'll just end up with old drafty windows with expensive glass :). Or have same frame style windows manufactured which will probably cost a fortune.

MikeAqua

7773 posts

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#1792234 31-May-2017 11:31

You can get double glazed wooden joinery made to match character homes. It costs more but is worth it if you are doing a faithful rennovation.

I've even seen it made to match those black steel framed windows - visually worked and in-distinguishable from adjacent buildings.

Mike

tdgeek

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#1792237 31-May-2017 11:35

MikeAqua:

You can get double glazed wooden joinery made to match character homes. It costs more but is worth it if you are doing a faithful rennovation.

I've even seen it made to match those black steel framed windows - visually worked and in-distinguishable from adjacent buildings.

The builder doing ours replaced the wooden frames, they look great As as my painter said, wow what a good job. They don't look retrofitted

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antoniosk

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#1792254 31-May-2017 11:48

eph:

Sorry I don't but just out of curiosity if you were adding/replacing windows why would you ever consider going single glazing??

In a 100 year old house you will find the wood framing is likely to not be man enough to hold the weight of a double glazed window - and, there will inevitably be gaps around the edges meaning you have an expensive window not doing it's job.

I replaced 3 windows with heavy stuff at our house, but in hindsight it would have been better to replace the entire framing and buy a new all in one (there were reasons why i couldnt)

________

Antoniosk

antoniosk

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#1792258 31-May-2017 11:51

sbiddle:

Double glazing is not, and never has been a legal requirement to meet the building code.

A property needs to meet certain energy efficiency guidelines and figures which are different across the country. One way to meet those requirements is to install double glazing and in all honestly if you are building a new house you'd have to be pretty crazy not to install double glazed windows.

Yep.

When you're renovating a house, you fall under new building codes which have statements on thermal efficiency for the WHOLE house, not just the new bit.

Inevitably, unless you're also addressing the rest of the house and it's problems, the new side will need to compensate for the bit that isn't pulling its weight.

So says the building code (for welly at least).

You can do things like underfloor insulation, wall insulation, replacing duff windows etc, but it's all cost that mounts up (very fast).

If you have a character home with lovely rimu and kauri, there is value in protecting that look. For a modern home with no soul... well might be cheaper to knock down and start again (and NO gst on materials for new builds - it makes a difference)

________

Antoniosk

timmmay

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#1792276 31-May-2017 12:16

I woudn't put in a single glazed window, and if I was redoing anything I'd go double glazed.

I put in a single double glazed window 5 years ago, in the style of the house. It's annoying because I still have to paint it like a regular window. The newer uPVC I put in this year are much lower maintenance.

afe66

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#1792292 31-May-2017 12:46

I have 1918 villa with probably the original front and back doors with a heat pump in the connecting corridor. When we bought it, wind would blow around the warped doors and cancel the heat pump.

So we replaced the doors, put draft stop ledges and replaced the glass around the front door and backdoor/laundry with retrofit double glazing in existing wooden frames.

Major improvement. You have to look carefully to see not original windows.

Bung

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#1792297 31-May-2017 12:58

antoniosk:

Yep.

When you're renovating a house, you fall under new building codes which have statements on thermal efficiency for the WHOLE house, not just the new bit.

Inevitably, unless you're also addressing the rest of the house and it's problems, the new side will need to compensate for the bit that isn't pulling its weight.

So says the building code (for welly at least).

You can do things like underfloor insulation, wall insulation, replacing duff windows etc, but it's all cost that mounts up (very fast).

If you have a character home with lovely rimu and kauri, there is value in protecting that look. For a modern home with no soul... well might be cheaper to knock down and start again (and NO gst on materials for new builds - it makes a difference)

The renovation has to comply with H1 but the rest of the house just can't be worse off because of the addition. Adding an H1 window is still worse than a wall so something needs to compensate but the rest doesn't have to be brought up to H1.

https://www.building.govt.nz/building-code-compliance/h-energy-efficiency/h1-energy-efficiency/repairs-and-replacements-h1-compliance/additions-and-extensions/

I can't find any reference to building material for new houses being zero rated - link??

kryptonjohn

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#1796420 8-Jun-2017 09:28

In our current renovation (Auckland) we had to replace the bathroom windows as they weren't safety glass. Didn't have to replace them with double glazing though.

doublek69

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#1796464 8-Jun-2017 10:09

Depends on what the alterations are. If they are cosmetic (and not consent dependent) then no need.