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Community and Q&A

How to choose the right replacement windows

X9h3VQQgpb | Posted in General Questions on

I have two very large windows on the south side of my house, 1-98″x72″ and 1-121″x72″. Both windows are covered by overhang porches but do have sun directly on them certain times of the year. I live in central Oklahoma where it gets really hot in the summer and fairly cold in the winter. I have found some replacement windows that have a u factor:0.31 and a shgc: 0.28 and I am needing to know if this is the best choice for the region I live in. I would appreciate any and all help, thanks.

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  1. bdrfab | | #1

    What times of the year do they receive direct sunlight? If summer, the lower the SHGC number, the better. If winter, higher is your friend. The lower the U-value, the better. U value= 1/R value. Buy the best window your budget will allow.

  2. cbedgar | | #2

    When we replaced windows in San Diego, we went with "Magic Windows" by Canadian Thermo Windows. It was the salesman who talked us into them, and we just wanted a well made, low E, dual pane window that was going to last.

    We were extremely happy with the windows. Now we have moved to upstate New York and we have a combination of Anderson and Pella windows and doors. These are all high quality, dual pane, low E windows and doors with wood on the inside and vinyl or steel on the outside. And we really miss our Magic Windows.

    The Magic Windows we had were steel reinforced vinyl and extremely durable and well made. Their insulating performance was great (but San Diego is not much of a test!). We knew the noise insulation worked really well because they not quite, but almost silenced the jets always flying overhead. We really liked the retractable screens and the crankless casement windows. I can't justify replacing our high quality Andersons, but I would buy Magic Windows if I needed windows for an addition or something.

  3. gusfhb | | #3

    I am going to guess that your windows with porches get sun in the winter. If that is the case you would want high solar heat gain coatings. Most of the companies have a version.
    I am also guessing that you are not talking about mounted windows in frames, but IGU's IOW, just the glass.

    With windows that big, transportation and installation might just dwarf the cost of the window. Find out who has a factory closest to you and what installer carries them. Shipping and crating for some IGUs I recently purchased was $1000, so I added some additional smaller units that became basically free.

  4. GBA Editor
    Martin Holladay | | #4

    It sounds like you have a question about glazing specifications rather than about which brand of window to choose. You might want to read this article: All About Glazing Options.

    My own two cents: as long as these windows remain mostly shaded during the summer, and receive most of their sunshine hours during the winter, you want to choose glazing with a higher SHGC.

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