Replacement Windows - Sanity Check, Please!
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While my house was built just six years ago, it is still old enough to have been constructed when local codes allowed the use of single-pane glass. To make matters worse, all the windows are aluminum framed (mostly single-hung & a couple sliders). Many of these twenty-six (26!) "thermal holes" are very large; my HVAC system & my utlity bills need a brake!
After careful consideration of the various options, including affordability, I need specific feedback on one solution that I am considering seriously.
Sandwiched between the wood framing and the brick veneer, the original glazing is in very good shape and the two-inch frames leave nearly five inches of untapped depth in the sheetrock-finished window returns. These windows will be left undisturbed to act as exterior storm windows. New insualting dual-pane three inch vinyl\wood insert\pocket windows, which require the least amount of demolition prep., will be installed inboard of the original system in the deep window returns. End state will be three total panes of glass in a more comfortable & more affordable home.
Please weigh-in with your concerns & solutions. Thank you very much.
After careful consideration of the various options, including affordability, I need specific feedback on one solution that I am considering seriously.
Sandwiched between the wood framing and the brick veneer, the original glazing is in very good shape and the two-inch frames leave nearly five inches of untapped depth in the sheetrock-finished window returns. These windows will be left undisturbed to act as exterior storm windows. New insualting dual-pane three inch vinyl\wood insert\pocket windows, which require the least amount of demolition prep., will be installed inboard of the original system in the deep window returns. End state will be three total panes of glass in a more comfortable & more affordable home.
Please weigh-in with your concerns & solutions. Thank you very much.
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Original windows will be left in place while new insert \ pocket windows will be installed to the interior side of the "old" windows.
Question: What, if any, will be the unintended negative consequecies of this arrangement
Thanks again.
Question: What, if any, will be the unintended negative consequecies of this arrangement
Thanks again.
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Sounds like a good plan. Check on how the new windows will be trimmed/finished on the inside. Will they have exposed jambs that will need to be trimmed with casing?
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Window + Window = Usually Bad Idea
Yikes where to begin. . .
There are numerous disadvantages of adding an interior window in addition to the existing interior windows that are being kept in place. Here we go:
1. If the new or old windows are vinyl, they can melt/distort if both old and new are left in place. Here's why: Vinyl windows function just fine without storms and are not intended to have them. If storms are added (your original windows would be functioning as storms if left in place as you proposed) the temperature between the inside and outside windows could exceed 158°, which could distort the vinyl as it begins to soften. It isn't clear if your new windows are to be vinyl, so this may be a non-issue. That's also one of the reasons vinyl windows are not typically offered in dark colors - the darker colors would absorb more heat and could lead to vinyl profile heat distortion. Again, nothing wrong with vinyl windows, if used as they are intended to be used.
2. You would be negating the ease of cleaning that replacement windows normally offer. Modern windows normally are cleaned from the inside. By adding inside windows to the already existing windows, not only would it be difficult to clean the exterior windows, but the way they are removed is probably blocked by the new windows you are adding. There would possibly be no way to tilt them in or remove them in case of breakage!
3. If the new windows are double glazed with Low E glass and argon gas, the third layer is largely unnecessary. A single glazed window like you have now would be approx. 14° center of glass temperature if the temperature was 0° outside. Adding a single glazed storm increases that to approx 45°, so it is really worth it to add a storm (preferably aluminum or wood) to a single glazed window. That's a 31° increase. However, if you have double glazed Low E with argon, the center of glass temp is 57° WITHOUT a storm, and is much easier to clean. Adding a storm only increases it to 60°, which is only a 3° increase. It's not necessary and makes it harder to clean.
You mentioned your existing windows are aluminum. Great, you can leave them on. But I would strongly recommend taking them OFF if you're getting vinyl windows on the inside. If you're leaving the originals on for the exterior, then it would probably be best to use aluminum windows on the interior as well. There are aluminum window manufacturers that make just such a window to fit into the drywall-to-drywall openings for that very purpose. I've most commonly seen them on apartment buildings. Good luck with your research and decision!
There are numerous disadvantages of adding an interior window in addition to the existing interior windows that are being kept in place. Here we go:
1. If the new or old windows are vinyl, they can melt/distort if both old and new are left in place. Here's why: Vinyl windows function just fine without storms and are not intended to have them. If storms are added (your original windows would be functioning as storms if left in place as you proposed) the temperature between the inside and outside windows could exceed 158°, which could distort the vinyl as it begins to soften. It isn't clear if your new windows are to be vinyl, so this may be a non-issue. That's also one of the reasons vinyl windows are not typically offered in dark colors - the darker colors would absorb more heat and could lead to vinyl profile heat distortion. Again, nothing wrong with vinyl windows, if used as they are intended to be used.
2. You would be negating the ease of cleaning that replacement windows normally offer. Modern windows normally are cleaned from the inside. By adding inside windows to the already existing windows, not only would it be difficult to clean the exterior windows, but the way they are removed is probably blocked by the new windows you are adding. There would possibly be no way to tilt them in or remove them in case of breakage!
3. If the new windows are double glazed with Low E glass and argon gas, the third layer is largely unnecessary. A single glazed window like you have now would be approx. 14° center of glass temperature if the temperature was 0° outside. Adding a single glazed storm increases that to approx 45°, so it is really worth it to add a storm (preferably aluminum or wood) to a single glazed window. That's a 31° increase. However, if you have double glazed Low E with argon, the center of glass temp is 57° WITHOUT a storm, and is much easier to clean. Adding a storm only increases it to 60°, which is only a 3° increase. It's not necessary and makes it harder to clean.
You mentioned your existing windows are aluminum. Great, you can leave them on. But I would strongly recommend taking them OFF if you're getting vinyl windows on the inside. If you're leaving the originals on for the exterior, then it would probably be best to use aluminum windows on the interior as well. There are aluminum window manufacturers that make just such a window to fit into the drywall-to-drywall openings for that very purpose. I've most commonly seen them on apartment buildings. Good luck with your research and decision!