Sealing gap between window frame & brick exterior
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Vinyl windows, brick house. From the exterior, there is a gap between the aluminum flashing & the brick. Lots of dust / hair / etc. in there. After cleaning the crap out, am I correct in the assumption that I would use concrete/polyurethane caulk as opposed to rubber caulk (since my two materials that I'm joining are metal + brick)?
#2
Yes, I prefer polyurethane when caulking brick. Vulkem is a good choice. NP1 is another... Tremco Dymonic FC is another. Vulkem is readily available at the big box.. Grey or limestone or concrete colors... for the others, you usually need to find a commercial building material store.
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In absence of caulk between this gap, is this a surefire entrypoint for air/water?
Reason I ask is because I took the interior trim off the window & didn't feel any air leaks (though there is a small gap between frame & wood), and there it looks like there's fiberglass stuffed in the gap (from the outside).
Attached 2 images
Reason I ask is because I took the interior trim off the window & didn't feel any air leaks (though there is a small gap between frame & wood), and there it looks like there's fiberglass stuffed in the gap (from the outside).
Attached 2 images
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IMO, any gap at the brick/flashing will not infiltrate to the inside if the interior of the window is foamed at the sheathing/stud edge. A gap out there will feed the 1-2" air space required behind the brick veneer. Use canned foam inside, under the trim; "Location";Info-406: Air Sealing Windows — Building Science Information
You don't want/need to caulk a gap at the head- over the window, Fig.2b; Info-305: Reservoir Claddings — Building Science Information
Effectiveness of stuffing fiberglass to stop air; Airflow Performance of Building Envelopes, Components, and Systems - Google Books
Water/moisture will drive through the brick on a sunny day; http://www.buildingscience.com/docum...n-brick-veneer
but your window should be part of the drainage plane;http://www.buildingscience.com/docum...d-wall-systems
Gary
You don't want/need to caulk a gap at the head- over the window, Fig.2b; Info-305: Reservoir Claddings — Building Science Information
Effectiveness of stuffing fiberglass to stop air; Airflow Performance of Building Envelopes, Components, and Systems - Google Books
Water/moisture will drive through the brick on a sunny day; http://www.buildingscience.com/docum...n-brick-veneer
but your window should be part of the drainage plane;http://www.buildingscience.com/docum...d-wall-systems
Gary
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Indeed, whoops... Just be sure to use a backer rod with the caulk/sealant for a proper tooled joint (hour-glass shape) that will move with two very different rates; pp.35; Architectural Detailing: Function - Constructibility - Aesthetics - Edward Allen, Patrick Rand - Google Books
Handbook of Sealant Technology - Google Books
Sorry for the multiple links, but they each cover different added info; http://www.cpci.ca/downloads/Sealant...t_Brochure.pdf
Exterior Siding, Trim, and Finishes - Google Books
Gary
Handbook of Sealant Technology - Google Books
Sorry for the multiple links, but they each cover different added info; http://www.cpci.ca/downloads/Sealant...t_Brochure.pdf
Exterior Siding, Trim, and Finishes - Google Books
Gary
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You are welcome, I have more, though they are on wood/wood with backer rod/caulk. Same principle though, if you don't use backer rod; the caulk will not last long alone against thermal/capillary movement.
Gary
Gary
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Backer rod might be tough because the gap between the window and brick is not an even gap the full vertical length, and the smallest backer rod I could find was 3/8". Gap varies from about a 16th to a quarter inch. I already know my caulk job is gonna look horrible!
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Try a window installer or window supply acc. on the web...Box store usually carry limited thicknesses, here anyways. Page 32 shows one alternative;Exterior Siding, Trim, and Finishes - Google Books
Gary
Gary