Aluminium Window Replacement Recommendations

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Eva888

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#324476 15-Apr-2026 09:23

After the last storm and related water egress I must replace the 70s aluminium windows. I’ve read the older GZ thread. Can anyone recommend a company in and around Wellington. It’s for an extreme wind area so want a very experienced team. I would get toughened or laminated glass in the exterior portion. We already have this glass at present and wish we could reuse it to save costs but unsure if this is a possibility and if glass degrades.

Don’t want to retrofit as frames have been battered and also don’t want PVC because of the need for high strength.

There will be a premium for the years of procrastination but that last storm shocked me with sodden carpets and drama. Appreciate any input.

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Smpl Mnmlst
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#3480960 15-Apr-2026 09:41

Even if you’re not required to fit double-glazed joinery, may I suggest you look seriously at this. Will be a budget hit but IMO d-g is fantastic. It has benefits apart from the obvious thermal insulation.

A lot of people don’t know how great it is until they experience it - we certainly didn’t. Now we could never live in a place without it.

Sometimes I just sit and think. Other times I just sit.

Eva888

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#3480996 15-Apr-2026 11:38

Just had a man to quote. I suspect telephone numbers as both inside and out panes have to be 5mil safety glass and frames priced for extreme conditions. Will get a few more quotes.

KiwiSurfer

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#3480998 15-Apr-2026 11:46

Second double glazing. Our new build we moved in 1-2 years ago is double glazed and we noticed the difference from Day 1 and still marvel at how well it works. We live next door to the in-laws older 1970's house which (until recently) was not double glazed and we can tell the difference on hot/cold days -- our DG house is still comfortable where their house just next door is either way too hot or way too cold. Only thing to be careful of is to keep all windows closed durng hot/cold weather to trap the cold/heat air inside otherwise there's no point. In-laws ended up retrofitting to double-glazing but unforutntly they keep their windows open all the time (old habits die hard) and complain it doesn't work. YMMV but if you can get double glazing and make use of it correctly it's a game changer.

SirHumphreyAppleby

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#3481010 15-Apr-2026 12:18

You may also consider thermally broken aluminium joinery. We didn't opt for that in Auckland, but did add double glazing to my grandmother's place. It certainly has made the house feel warmer.

Modern profiles tend to be a lot larger than those used in the'70s, so if you want to preserve the original look, you may want to consider multiple options and not just price. I also recommend sticking with anodized, even though it's a little more expensive and may not look quite as good as the old stuff.

Eva888

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#3481019 15-Apr-2026 13:29

Good point about the modern profiles. I need to ask how wide the mullion will be down the middle. We have a view and I would dearly love to get rid of a center mullion but a bit concerned about the glass strength without one.

Jase2985

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#3481044 15-Apr-2026 14:55

What makes you think PVC isnt high strength?

"uPVC windows are an excellent choice for high wind zones in New Zealand, offering structural strength and weathertightness up to "Extra High" wind ratings"

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timmmay

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#3481070 15-Apr-2026 16:17

Yeah I'm not sure why you think PVC isn't suitable. I'd at least ask about it.

5mm thick glass is pretty crazy? What is so extreme it needs that much glass?!

tweake

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#3481141 15-Apr-2026 18:12

i would give pvc a 2nd look, from what i've seen is they have steel bar inside the profile for strength.

any new aluminium frames will be thermally broken (doesn't hurt to check). old school will be 2nd hand or special order which increases the cost.

i would allow extra $$ for repair to the house framing. highly likely to have some rot around those windows and you probably want to upgrade the sill protection, as those era houses had none.

Eva888

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#3481244 16-Apr-2026 09:11

timmmay:

Yeah I'm not sure why you think PVC isn't suitable. I'd at least ask about it.

5mm thick glass is pretty crazy? What is so extreme it needs that much glass?!

The wind is extreme here so everything facing South is at the highest extreme rating.

Years back in a storm one of the windows broke and we replaced with 6ml laminated glass. Two shards got shot 4 meters and imbedded into the wood on the opposite side of the room. I doubt PVC has been rated for extreme windconditions together with salt spray. The aluminium frames are still solid but it’s the old design that fails it and also the laminated glass was put into frames that weren’t designed for it.

Am also concerned at the fuel situation and the effects on materials. Timing as always is everything.

Jase2985

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#3481327 16-Apr-2026 14:45

Eva888:

I doubt PVC has been rated for extreme wind conditions together with salt spray. The aluminium frames are still solid but it’s the old design that fails it and also the laminated glass was put into frames that weren’t designed for it.

Am also concerned at the fuel situation and the effects on materials. Timing as always is everything.

@Eva888 you have completely glazed over my statement.

I think a lot of your concerns are unfounded based on the current range of uPVC windows.

Aluminium is also being affected due to the fuel situation

Its worth a look.

Jase2985:

What makes you think PVC isnt high strength?

"uPVC windows are an excellent choice for high wind zones in New Zealand, offering structural strength and weathertightness up to "Extra High" wind ratings"

pdh

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#3481339 16-Apr-2026 16:17

Both the houses I've had built for me in Auckland have been in high wind zones.
Wellington just gets it more continuously ;-)

I looked at plastic very hard for the current house - in the finish I went for wood/ali for aesthetic reasons.
It would not occur to me (as a mech eng) that PVC framing would not be tough enough for the job.
Some of the really big PVC frames do have metal reinforcement inside.
Coke tins are ali - rubbish bins are plastic. Which survives being hit with your car ?
It's all of the design choices that combine to give strength - not just the materials.

Yes double-glazing is wonderful - but I knew that, having grown up in Montreal.
It continues to amuse me that on my first house (1993), every tradie on site laughed at me using DG.
By the second house (2020) - 7 km away from the 1993 one - it was required by Auckland Council regulation...

If you are going through the process of putting in new windows, think about putting in different size units for more light, more views or more ventilation. The additional cost of doing so may be minimal - especially if there is rot / water damage in the old wall timbers. You now have the choice of improving a room.

One of my favourite YouTube channels is a good kiwi bloke / pro builder who is getting to be world-renowned for his Makita Tool reviews (finally someone in the trade - rather that just an influencer who obsesses about unpacking the cardboard box - but I digress).

Check out Scott's video from last week - where he helps a mate put in a just-a-bit-larger replacement window in a Nelson house.
https://www.youtube.com/watch?v=kcdv1kktGpk

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eracode

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#3481345 16-Apr-2026 16:47

Jase2985:

@Eva888 you have completely glazed over my statement.

We see what you did there. 😀

Sometimes I just sit and think. Other times I just sit.

tweake

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#3481364 16-Apr-2026 18:37

pdh:

If you are going through the process of putting in new windows, think about putting in different size units for more light, more views or more ventilation. The additional cost of doing so may be minimal - especially if there is rot / water damage in the old wall timbers. You now have the choice of improving a room.

the problem with changing sizes is the cladding.

but if cladding was not a problem, i would seriously look at downsizing the windows and removing opening windows.

most 1970-2026 design houses are way over glazed. size has a huge impact on solar gain (ie hot house in summer) and insulation. going smaller helps with both and its cheaper provided the cladding can be sorted.

who uses windows for ventilation anymore? i would always have a window for fire escape, but otherwise reducing the amount of opening windows cuts costs and improves weather resistance.

eracode

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#3481367 16-Apr-2026 18:46

tweake:

i would seriously look at downsizing the windows and removing opening windows.

most 1970-2026 design houses are way over glazed. size has a huge impact on solar gain (ie hot house in summer) and insulation. going smaller helps with both and its cheaper provided the cladding can be sorted.

who uses windows for ventilation anymore? i would always have a window for fire escape, but otherwise reducing the amount of opening windows cuts costs and improves weather resistance.

Yeah, who needs windows anyway. Go the whole hog - fill ‘em all in, block ‘em all up. Y’all be better off.

Sometimes I just sit and think. Other times I just sit.

Eva888

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#3481387 16-Apr-2026 20:38

The windows are in a lockwood so difficult to change anything size wise for a number of reasons. Ok will consider PVC if they can convince me of the durability.

Am told that they put the area in the computer and it spits out what the area council requirements are and what glass thickness etc.

It’s a depressing time to be doing any renovations with all the uncertainty and my hearts not in it.

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