Have you retro fitted U-PVC Tilt & Turn windows?

digmen1, Jun 23, 6:50pm
These new U PVC tilt and turn windows look great.

Has anyone retro fitted them to their house?

I would love to do my bedroom it has two windows.

They look very expensive.

budgel, Jun 23, 9:15pm
Does anyone know if Branz has checked the UPVC windows out and passed them?
I still have nagging doubts about PVC longterm in the NZ context.

carter19, Jun 23, 9:50pm
The info on the WANZ website is not very encouraging

mm12345, Jun 24, 2:49am
Of course BRANZ have approved uPVC joinery.

The NZ aversion to them is legacy from the Muldoon years, where there was large investment in a NZ owned smelter, as well as investment in aluminium extrusion / fabrication. UPVC was a serious threat and there was a propaganda campaign to discourage it's use. Fortunately, those days are over - even if for better or worse some people have long memories.

digmen1, Jun 24, 3:22am
My only reservation would be their tolerance to our high uv rates.

They seem to be very popular in the UK and Germany which have very harsh winter.

I'd still like to hear from someone who has them.

carter19, Jun 24, 4:30am
After checking the Branz website i would be very annoyed if i had to replace my windows and doors after 15 years

mm12345, Jun 24, 4:36am
You realise that if you're fitting double-glazed units now, they're probably going to need replacing in 15-25 years anyway (unless you like foggy windows).

lissie, Jun 24, 9:49am
ACtually they are not that expensive - I have some prices - and it's cheaper than what the builder had allowed for standard power coated doubled glazed aluminum- and far better in terms of heat loss.

Thermalframe - in Wgtn - installed windows in a ski lodge on ruapehu - 20 years ago - I figure that will do me even though we are very coastal. I can't see power-coated al lasting at all well in an extreme coastal environment

I liked the tilt and turn too - but the issue is window coverings - you have to leave clearance at the top of the window- tricky with blinds or curtains. The Europeans tend to use external shutters

digmen1, Jun 24, 5:46pm
@lissie
Thanks for that.
I hope to get some prices soon too.

I am lucky in that the bedroom I want to double glaze does not get much sun, so the perception that U-PVC is not good in high uv areas will not apply to me.

A good point that you mention about clearance for tilt and turn. I will have to look into that to see if it is really a problem.

carter19, Jun 24, 10:38pm
Mm12345 can you exkain that in mor detail please?

mm12345, Jun 25, 6:00am
The seals break down in double-glazed units, once the desiccant inside the unit has taken up it's limit of water, then water will condense on the glass inside. The seals can't completely stop water vapour, and the window glass is at different temperature inside and outside, thermal expansion constantly stressing the seals. Sometimes the windows on the sunny side of the house fail first, sometimes the shady side - only one thing certain - they will eventually fail.
It generally doesn't make sense to replace existing single-glazed windows with double glazed - the potential energy saving doesn't even come close to the cost. Double-glazing companies will say this isn't true, but they also won't even offer a 20 year warranty for their product.
It might be worth doing for other reasons, comfort in a cold room, noise etc.
Different for a new build, where the extra cost for double glazing isn't much, or you're replacing rotten old joinery in an old house - even if you're allowed to single-glaze.

digmen1, Jun 25, 7:17pm
@mm12345

Very interesting.
Do you mean that all double glazed windows have this problem or just retro fitted ones.
I believe there are two sorts of double glazing -
Ones where they come and put an extra pane on top of your current windows.
The other which is a complete whole unit.
Obviously the latter is better but more expensive
Do all double glazed windows have this desiccant you speak of?

jane310567, Jun 25, 10:12pm
mm12345 - i've never heard of this - I thought you got condensation with magnetic acrylic double glazing but haven't heard of it in sealed units. I'm about to retro glaze so will have to do some research on this!

mm12345, Jun 25, 11:52pm
Yes - you do need to do some research on it if considering retrofitting double-glazing (as well as face the reality that with an older single-glazed house, there will possibly be many other things which could be done to improve thermal performance which may make a bigger difference and will be worthwhile).
It's not just "retro-fitted" double glazing which fails. They all fail.
With a new build, you've probably got no choice. You may have some choice if reglazing is part of a major renovation, but it might get very tricky.
https://en.wikipedia.org/wiki/Insulated_glazing#Longevity

digmen1, Jun 26, 7:00am
@mm12345
You seem to be a bit of a luddite, when it comes to windows. Or maybe you have shares in an aluminiun company.

The whole world is moving to U-PVC double glazing, It has been used in Germany since the 1960's.

http://www.upvc.co.nz/cost-comparison.html

They say UPVC can be cheaper.
It has far less (or no) condensation, whereas aluminium has very high condensation rates. (My bedroom windows are wet every day lately)
There are multiple locking pits - far better security.

You many be part of the BRANZ/buliders/artcihets/suppl-
iers consortiums that bought us leaky homes!

mm12345, Dec 7, 1:53am
Not sure what planet you're on - but not Earth perhaps.
Try reading what I wrote.