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kens85

Replacing glass block windows

KenS85
10 years ago

I need a little help. I've gutted and I'm remodeling my basement apartment in a 3-flat building. Right now all the windows are glass block and i want to swap a couple of them out for double hung because 1 is broke anyways and it would be nice for a window A/C unit. So my question is, the building is all brick and the glass block windows are just mortared in flush with the outside. There is no frame at all inside the window, just concrte/brick. Do i need to build a small frame all the way around using 1x4's or something and then order the window to the demensions inside my frame? Or can i order a wnidow that will just fit perfectly in the brick? I'm assuming it would be hard to seal it this way.... I'm really not sure what the best way to go is. I appreciate any advice i can get. I'll try to post some pictures later to help visualize.

Comments (14)

  • geoffrey_b
    10 years ago

    You can order windows without a flange (nailing flange). You order the window by the size of the rough-in opening.

    The window is attached by drilling through the sides of the window frame, and into the wall. Depending upon how thick your wall is - or how you can attach the window you many need to build a frame - but if you do - then you will need some moulding to cover up the frame on the outside.

    Here is a link that might be useful: Hy-lite Windows

    This post was edited by Geoffrey_B on Tue, Jun 4, 13 at 16:00

  • KenS85
    Original Author
    10 years ago

    So let's say i dont build a frame and i just attach the window to the brick/concrete. What do i put on the outside to seal it since i can't add flashing tape to the brick. Do i just use a silicone caulking? Or do i have to get some type of brick molding?

  • KenS85
    Original Author
    10 years ago

    Thanks for the advice!

  • PRO
    Windows on Washington Ltd
    10 years ago

    We typically set them in a buck for ease and a more secure attachment but you can certainly set them brick to brick and seal them.

    I, personally, would not run silicone for the fact that it is not as easy to tool a bead or lay down.

    At the end of the day, the sealant will probably provide as much of the attachment to the structure as the screws will.

  • KenS85
    Original Author
    10 years ago

    What size wood should i use to build the buck then? And then I order he window with a flange that will just screw into the buck right? Also, what sealant are you talking about if you don't use silicone? Will I also need some kind of brick mold for the outside? Thanks again.

  • geoffrey_b
    10 years ago

    IâÂÂve replaced several windows in my brick/stone home. HereâÂÂs how they were done (in 1950):

    From the outside: removed brick moulding, the 2x4 framing extended about þâ into the window opening. The window opening was framed with 1x4âÂÂs. The 1x4âÂÂs were attached to the 2x4âÂÂs.

    The windows were set inside, and attached to the frame. The brick mould was about 1 ýâ it overlapped the þâ of 2x4 and the þâ of the 1x4.


    Before you start, see what width brick/sill moulding is available. All I could find was 2â so I made my window framing (the 1x4) wider with ýâ plywood.

    The flange moulding is really meant for siding or stucco. I donâÂÂt think it will work well to nail brick moulding over it.

    IMO, you just need a few screws: The window and door foam does a good job at holding the window in place.

  • PRO
    Windows on Washington Ltd
    10 years ago

    +1

    Foam will lock it in good.

    In terms of sealant, any good exterior sealant will do the trick.

    OSI Quad is somewhat of the unofficial industry standard.

  • KenS85
    Original Author
    10 years ago

    Thabks again for all the help! I'll post before and after pictures when I finally finish!

  • KenS85
    Original Author
    10 years ago

    So I ordered a new double hung window that is going to come with a nailing fin. I'm going to use pressure treated 2x4's to create a buck and then nail the fin to that. Then I'm guess i can just put silicone all the way around oh and also use the spray in foam as well. Once the window arrives and I see it I'll have a better idea of how the install will go I think.

  • millworkman
    10 years ago

    If you use spray foam be careful and make certain you use the minimal expansion type.

  • KenS85
    Original Author
    10 years ago

    Yeah I heard use the one made for windows and doors because it doesn't expand as much. Do you recommend something to use besides the spray foam? Seemed like the easy way to go.

  • millworkman
    10 years ago

    it would be easier, the only other way is to use backer rod and caulk!

  • KenS85
    Original Author
    10 years ago

    ok. Well my plan was to use the spray foam in the big cracks and then still caulk around the outside. Thanks again!