Double Glazing worth the cost?

Hi All,

Probably been covered somewhere in this forum, wondering if Double glazing is REALLY beneficial/cost effective to a home.
I will be installing a 6m timber stacker door in the dining/lounge area, it is facing North/North West. I have been quoted $6500 for single pane, waiting back to hear a proper quote for the double glazing. I have been told it will be double the cost.
Is it really worth $13000?

We've got double glazing throughout and it does make a big difference to temperature and noise. I can't help you with the extra cost as we asked them to quote on double glazing to begin with.

I have heard that there's nowhere near as much benefit just having one or two doors / windows double glazed and the rest single but the experts would be able to advise on this better than I can.

this wont really apply as not in oz, but our whole house was $7k more for double (26k) so we went for it
we have a 4.6 stacker door in family room, facing east.
no window coverings on it (I wanted to see the view always) keeps the warmth in in winter, cos of the double glazing and no condensation.

our whole house doesnt get watery windows and this past winter we had a fan heater on for an hour , 4 times.
The double glazing keeps the house warm in winter (we are top of nz) and cool in summer. I would have it in a heart beat again, but the whole house. If it is 13k for one window, you have a larger home than ours.
(ours is 242 sq mets)
its is budget thing.

to go from the builders inclusion which was commercial quality aluminum with 5mm glass to all double glazed with 6.38mm glass 12mm argon gap and 6.38mm glass in thermally broken aluminum is about 20K more including a 5m two pane heavy stacker. I think for me it is a worth while upgrade for sound and heat insulation. I also like the tilt and turns that make cleaning upstairs windows easier.

As kiwi says' "its a budget thing" compromises will have to be found elsewhere.....

Ciao and good luck with the decision

Mark

No definitely not worth it at that price... but neither is the door... get some more quotes if you really have to have timber. In aluminium, we can supply the (2.1 high) 6m wide door in double glazing at $3050...

BTW... the orientation has no relevance to double glazing - if you want to control solar heat gain, then you will need to add low-E glass to the double glazing.

Ed

Ed, I'm sure you've commented on this a billion times before ... but am I right in saying that a lot of the time you get better performance from a properly-designed frame (dare I mention your thermally-broken uPVC ones as an example for fear of looking like a fanboi or something? ) than from the glass itself, at least with respect to insulative properties?

To give a for-example, the builder we've been looking at using has a policy of only using their existing suppliers; their window supplier is one of the big names everyone's heard-of. Their aluminium double-glazed windows have worse WERS ratings (both hot & cold) than their timber-framed windows with single-glazing; the difference not being in the glass, but in the fact that their aluminium frames aren't thermally-broken (and their wooden ones sort-of are ... I guess due to being made out of the quite non-conductive medium of wood).

So to answer the original question but attaching an "according to what I've been told rather than in my experience" clause ... double-glazing works well, but IMHO if you're getting wooden frames you're not going to get a massive increase in insulation with double-glazing. We've been told by more than one architect that unless we're getting really fancy with our house, having laminated glass is generally going to offer enough insulation for us in Sydney as well as offering some security downstairs; of course it's going to be different if you're further south or further inland, and "enough" is a very objective term too!

The glass is a leveler as long as the different systems have the same gap (12mm being optimum) and same glass type - many systems were designed for single glazed and cannot fit a 12mm gap with 4mm or 5mm glass, so they don't perform anywhere near as well. After glazing, the frame design is the only differentiator, EcoClassic's non-broken frame (EcoTech) beats a market leader for energy efficiency, and theirs is thermally broken. (We also have a thermally broken window).

Timber is great, until it warps or needs painting. PVC is good until you want very large windows, or large sashes, or you are in a bushfire area.

Double glazing, with a 12mm airgap, with well sealed windows, will always deliver the same marked benefit over single glazed windows, in timber, aluminium, PVC or thermally broken aluminium.

And finally, laminated glass will make no difference to energy efficiency.

Ed

Re double glazing (DG). We had a problem with noise and looked at DG. The cost put us off - BUT we went to a large hardware place and got this special "rubber" tape that goes around the frame of a window. You then close the window - tight. The "tape" is in a few sizes so you can close the window properly. I guess its similar to that stuff you put around a door jamb to stop a draft - but its rubber and sits up a bit - max maybe a 5mm or so ?

It stopped almost 70-80% of the noise I'd say. You could still hear the noise - but as if from far away. This was a bedroom too.

Cost under $20 (from memory) vis a vis $1,000's for DG.

That will work if your problem is air leakage... when it's 3mm glass it won't help.

Ed

I think it was just the gap - so yes - but it worked a treat.

Deleted double post by mistake sorry