Triple-pane vs. Double-pane windows in SIPS home

[kutupembe]

I am in the process of choosing windows for a SIPS home to be built in northern Minnesota.

Here are the things I have heard:

Contractor- Don't waste your money on Triple-pane, the house is so well insulated that the difference in energy cost won't be worth it. Also, triple panes means two areas where seals can fail.

On this site- Energy savings is the same because the insulation advantage of the triple-pane is countered by the fact that it reflects more energy.

Friends - Dorwin (sp?) triple-paned have been great.

Friend - Really like H-window triple paned

I am looking for more advice. Thanks

[Joseph Meehan]

The better insulated the rest of the home is the bigger difference that tipple pane will make. In your area I would put them in myself. It is not just energy saving, but it is also comfort level. Somehow I suspect the contractor get's his best deal (most profit to him) for double pane.

[m Ransley]

How much glass area do you have planned, you go apx from R 3.5 to R 5 with tripple pane, windows are your weak point. You can also add 1-3 R with Cellular shades and curtains. What is frame material I hope not aluminum. You have one thing to consider even more important then tripple pane its Cdf or condensing factor. Pella are poor in Cdf and with sips higher humidity they will condense. They do in my house continualy without ever using a dehumidifier. Read an old Consumer Reports test of apx 23 windows, go to Energy Star, I dont know of what site you are refering to on your rating. Are you aware there are different LowE coatings for southern and northern designs.

[Tony Hwang]

Hi, Here in Calgary Alberta MOST houses have double pane windows. My house built in '94 has also gas filled E glass or whatever. ouse is R2000 spec. This house is cool in summer and warm in winter. I guess if both windows have same quality level triple pane will be bewtter choice. Window technology came a long way. In more than 10 year span I had one window replaced due to leaking seal.

[hallerb]

go to a window store with a light shinning on display windows.

see the same light shine thru single double and triple panes?

feel the difference its a LOT and then decide if its worth the $

Saw this recently at local hme show it was amazing!

[Calvin Henry-Cotnam]

For the glass area, triple gives you a better R-value than double, about

5 versus 3.5.

HOWEVER, the frame needed to support three panes of glass is a better thermal bridge than what is needed for double. On many windows, the gains in R-value for triple is offset, or WORSENED by the frame.

If you must have a large picture window, a triple-glazed window would likely make a big difference. Of course, shutters would also make a big, or even bigger difference as well.

In our home, our largest windows are 54" x 54" casement (two-section) and it just made no sense to go with triple-glazing.

[Joseph Meehan]

Interesting. I suppose that would be possible. Do you have any source of figures for it?

[m Ransley]

Aluminum is a thermal conductor, but wood and composites are going to have good R value. Even so only aluminum would figure into a degadation that shows in U values, the overall window rating. I hope aluminum is not being considered that far north, as all aluminum I see are realy U rated for southern areas. But true 50% of the loss can be the frame.

[Joseph Meehan]

I agree. I don't live that far north and I would not have aluminum fames, even those with a thermal break. My last home had aluminum without a thermo break. Really bad idea.

[L d'Bonnie]

A hundred or so miles north.

Those are all triple pane. They don't start sweating until it gets down to the neg. 30's. My cheap neighbors double panes are a waterfall by then.

Forget the hype, the marketing, and the no nothing experts.

Triple is the only way to go in cold country.

They are also better sound insulators. This is my front yard.

Boats and Seado's all summer, snowmobiles all winter. I hardly ever hear them. Barely notice the idiots with no mufflers.

[Calvin Henry-Cotnam]

Unfortunately, I don't. This was explained to me by a window manufacturer, who had a monetary incentive to sell me triple over double, so I consider "facts" coming from him that suggest I go the other way to have a little more weight to them than most "facts" thrown at me.

Looking at other posts, I see mention about aluminium frames and this jogs my memory a little more on this issue. The extra support that is needed for triple tends to come from aluminium components. Even with a thermal break, I tend to believe that the benefits of triple glazed windows over double are not realized until the area reaches a certain threshold.

What exactly that threshold is would be interesting and useful to know.

[Joseph Meehan]

Thanks for responding. Your logic makes sense, but of course the devil is in the details.

[mm]

I don't know what is better but the arguments here make no sense.

Triple pane isn't advertised to solve problems in the rest of the walls, only what leaks out the windows. It doesn't matter how good (OR bad**) the rest of the house is if enough leaks from the windows to be worth it.

**It matters how bad it is in that there may be heat losses that are greater, or cheaper to fix or to lessen. If one is not going to fix all heat losses. But he's saying that those others are well insulated. Therefore the question is, Are triple better than double enough to warrant the cost.

That's an arguement in favor of triple. If one seal fails the other will still be there. It's only if seals almost never fail that you could live with only one seal. Maybe he's confused with EXTRA windows, where each one that fails causes a leak. Would he say, Don't put in any windows because the seals might leak ?

Not sure.

There is a tendency for people to believe, to want to believe, they did the right thing.