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Replacing windows

windows1234 | Posted in General Questions on

We need to replace 21-year-old windows in a 2×6 wall.
Can I use 4″ windows?
If so, what are the modifications needed and are there any concerns we should be aware of?

Thanks.
KC

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Replies

  1. GBA Editor
    Martin Holladay | | #1

    Kathy,
    The short answer to your question is: yes, you can install the windows. To trim the windows out, you will need to install jamb extensions. Jamb extensions are usually built on site by a trim carpenter -- you can make them out of pine, hardwood lumber, or drywall -- but can also be purchased from some window manufacturers as an option. (No matter what type of jamb extensions you use, you will also need to install a stool. Most stools are made from softwood or hardwood lumber, but you can also use stone or solid-surface materials to build your stool.)

    The long answer to your question is that installing replacement windows can be tricky. While some replacement window companies do a good job, others quickly install new units in the old openings without considering water management issues. Ideally, every window rough opening needs to be flashed in such a way that the rough opening can handle leaks and can direct any wind-driven rain to the exterior.

    There are a range of possible responses to these issues. If your window openings are exposed to the weather (because of skimpy roof overhangs) in a wet climate, good water management details are crucial. If your window openings are well protected by a wide roof overhang and your climate is relatively dry, these details are less important.

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