Energy Efficiency of Double-Hung vs. Casement Windows
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building a house in mid-vermont, researching windows.
i read that casement are more efficient than double-hung,
but how much more?
is it like 5% or 500%?
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Replies
The difference will be somewhere in between the two numbers you mentioned. I don't have any specifics for you, and it's going to depend on the design of the window too. The big difference is that the many sliding seals in a double hung window tend to leak more air than the compression type seals used in casement windows. Casement windows are better in terms of air sealing, basically. This is the big reason why casement and awning windows are usually recommended instead of double hungs when energy efficiency is a primary concern. Where you usually see double hung windows going in is in historical areas where you have to match the style of the original window types used.
I recommend casement and awning windows over double hungs if you're after energy efficiency improvements. I also think those two types of windows are easier to operate.
Bill
Bill said "I recommend casement and awning windows over casements if you're after energy efficiency improvements. I also think those two types of windows are easier to operate."
I think Bill meant "I recommend casement and awning windows over ****double hung**** if you're after energy efficiency improvements. I also think those two types of windows are easier to operate.
Also, consider that we are learning (lots of info on this site) that the heating requirement of our houses is largely driven by air leakages. A casement window will normally have a much better seal and leak much less air. So you will no doubt save more on energy if you have casements but you will also be more comfortable (less cold) when you are near your windows in the house.
Yeah, that's exactly what I meant. Apparently I subconsciously don't like double hung windows :-) Thank's for catching my typo that made my recommendation not make much sense.
Bill
thanks guys, appreciate the input, will take that into consideration
I would also recommend casement and awning (or fixed) windows over double-hung. In my experience the double hung leak a lot more, the upper window tends to sag down over time, and they look a little funny without the muntins, which tend to clutter the views (imo, obviously).
Also, awning windows can be left open in mild rains, and casement windows, properly oriented, can catch a lot of breezes and direct them through the house. Way more better.
user...575,
I like awnings too. One downside though is I've never found one that met the egress requirements for bedrooms.
That's a good point about egress in bedrooms.
Most of the time when I've had awnings it was either as higher level transom windows, or lower level windows down near the floor with fixed windows above.