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gildomilo

Insulate around replacement windows

gildomilo
14 years ago

We bought our house a couple years ago. It's a 1929 Colonial. The prior owner replaced the windows. Although the windows themselves don't leak, you can feel air leaking through the edge of the frame. Tonight I pulled the molding off of one window. What I found was that the plasterers plastered right up to the original window frame. Therefore I'm not sure how I'm going to insulate around it. I was expecting to find a large cavity to fill with insulation. Maybe I just need to sneak some low expansion foam between the replacement window and the old frame? I can see the weight cavities, but have no access to get insulation into them. I'm wondering if maybe I should cut a little plaster away? I don't really want to ruin the walls....

Any advice would be appreciated.

Comments (10)

  • PRO
    Windows on Washington Ltd
    14 years ago

    Get a professional foam gun with the tapered nozzle and foam the whole thing.

    Best to apply foam in multiple small passes/amounts as opposed to trying to get it done in one fail swoop.

  • gildomilo
    Original Author
    14 years ago

    Where might one get a professional foam gun from? When you say foam the whoel thing, do you mean sneak the nozzle in between the plaster and the old window frame as well as in between the old window frame and the replacement window?

  • PRO
    Windows on Washington Ltd
    14 years ago

    Most building supply stores will have a foam application gun.

    The Hilti gun is my favorite and they sell a very narrow nozzle for thin applications.

    I would foam any areas that connect the interior living space with the exterior. Yes, foam it all.

    Here is a link that might be useful: Foam gun

  • gildomilo
    Original Author
    14 years ago

    Will the hilti gun fit in a 1/4" gap?

    Thanks,
    Gil

  • PRO
    Windows on Washington Ltd
    14 years ago

    They sell a small nozzle that is tiny and will fit just about anything.

  • gildomilo
    Original Author
    14 years ago

    I pulled the molding and insulated all of the upstairs windows. The only thing I haven't insulated are the window weight pockets. There is no access to them. The wall is finish plastered right up to the window frame has trim applied on top of it. Each of the 10 windows had anywhere from 1/8-3/8 of an inch air gap around it. So I'm sure we're 500X better then we were three hours ago. So the 5 million dollar question is, do I pull all of the trim (original), cut the plaster and fill the weight pockets, or leave well enough be?

  • PRO
    Windows on Washington Ltd
    14 years ago

    I would see how they feel now after the work you have done.

    If they are still cold, you can see about drilling a hole into the weight pocket and filling them that way.

  • gildomilo
    Original Author
    14 years ago

    Well I'm sitting upstairs with a t-shirt on, it's 30 deg and snowing. Yesterday I would have needed a sweatshirt to keep from freezing. When I do the first floor I'll do a before and after temperature comparison with the outside temp taken into consideration. Now what to do with the case of low expansion foam I bought :)

  • PRO
    Windows on Washington Ltd
    14 years ago

    There are plenty of spots in the home you can use it....trust me.

  • gildomilo
    Original Author
    14 years ago

    You can still feel cold are blowing in around the case molding. I could put some foam between the case molding and the wall, but that would probably just direct the air elsewhere.
    I wonder if it would be best to have insulation blown into the weight pockets from the outside. The bozos who did the windows left the darn weights in the pockets. In the downstairs we have double windows. I was able to pull the center panel and insulate the weight pockets with rigid foam and seal it up with expanding foam. I wish I didn't have to pull antique molding and cut plaster to get to the weight pockets on the single windows :).