Windows
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Not so much a question as a comment for discussion on windows. We are building a new house within a budget. We built our last house and basically followed the plans. We had a lot of windows and natural light in our last house which we really liked. However the window operation, double hung, fixed, casement, should have been chosen more carefully. I am all about air sealing our new house. To that end we have been reviewing window specs, u factors etc and also whether a window needs to be operational or not. My experience is that double hung windows are not utilized very much at least by us. We had three bay windows with a large stationary window in the middle and two side double hung windows on each side. In 18 years we probably opened the side windows five times. The bay window in the master bath required you to get in the tub to open the windows which we never did. Our new house will have mostly fixed windows here needed and a few casement followed by a few single hung because of size/cost. If I could afford to I would eliminate all single hung windows in favor of casement.
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Replies
Casements will give better air sealing than double hungs, but fixed windows will be the best in terms of energy efficiency. You might also consider something like the arrangement shown in the attached pic, which is a large fixed window with a smaller awning window underneath it. This gives you something of a mix, with most of the window fixed but a smaller operable part in case you want to get some ventilation.
Carefully plan which windows you might actually use. Fixed windows are more energy efficient but are also cheaper, so you can save some money this way. Note that code typically requires either an operable window or an exhaust fan in bathrooms so be sure to allow for this.
Bill
We have gone through several iterations on the windows to see which one we would actually open. In my experience double hung windows make no sense for current house construction. I have never opened the top sash of any double hung windows except to see if it worked, then I closed it and opened the bottom sash. What I have been told is people use to open the bottom sash half way and the top sash half way to get air circulation. Ok I guess that made sense before modern HVAC. However single hung windows seal better than double hungs as the top sash is fixed. Casements seal better than single hungs, and fixed windows seal best of all - no air leakage (if built correctly). We looked at each and every window on our new house plans and would ever be opened or not. About half of our windows will be fixed.
Double hung is nice if you have small children who are either at risk of falling out the window, or poking holes in the screen. You open the top for ventilation and leave the bottom closed.
Salesi,
Because the area that is useful as operable ventilation is usually much smaller than that for light and views, I usually break up windows so that only part opens - and that part I most often specify as an awning window, as they seal tightly and protect the opening from rain. The other reason to have only a small area operable is that large windows, especially vinyl ones, can have their frames distort over time compromising the seal. One caution is that awning windows don't meet the egress requirement for bedrooms under most codes.