I am installing a new vinyl window in an existing bathroom I have gutted. The wall is poured concrete. Any words of advice?
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Use only pressure treated lumber for the rough framing for the opening of the window.General rule of thumb, never use untreated lumber when in contact with masonry( the moisture off the masonry will cause rot in standard untreated 2x lumber)
Frank
Edited 8/10/2007 7:10 pm ET by Frankd479
good advice. one can also use untreated lumber if there is barrier provided ie: sill gasket. some guys also use both. View Image View Image
What makes guys use pressure treated for all wood in contact with concrete. Have you seen problems?
In the jurisdiction where I work, foundation walls only need to project 6 in. above grade, and there is no requirement for treated sill plates. Never seen a problem.
There probably will not be a problem but its just good practice to use PT. Concrete does retain moisture, so for the very little extra in money you know you are protected if the moisture content is high. In my area, sills are usually PT 2x6 and a KD 2x6 on top of that, all the older houses, even 30 years old have no PT and they rarely have problems. It just an extra insurance.
Do you need to cut concrete?
Yes I do have to cut the opening. This house is 35+ yrs old. None of the bathrooms had windows. Something I aim to change.
life will be easier if you hire a guy to cut it with a wet saw, where they bolt on to the foundation and make the cut.
you can also do it yourself with a wet or dry saw. regardless it will have to be a big gas powered cut off saw. if you go dry you will dust the whole neighbourhood. I think most gas saws have hose attatchment. View Image View Image
"life will be easier if you hire a guy to cut it with a wet saw"
I second that!
I have a wet saw. Cutting the wall isn't the hard part for me. It's framing the window properly and ensuring the opening is sealed properly. I understand what to do for a stud wall, but a concrete wall is new for me.
Edited 8/11/2007 2:01 pm ET by David T
well if cutting the wall is the easy part for you , you really should have no problem with the rest.
there is nothing hard about the framing. line the cut out concrete with your framing. use either PT as said before or use regular lumber with sill gasket between the framing and concrete. most the time there will not be an issue, esepecially with old concrete as in your case. new concrete still has a lot of moisture content, and it is more liekly to have moisture wick from the concree to the wood. but still it is a good habit. with you making a window well, the concrete will most likely get wet from the outside, with concrete being very porous, (depending on how your foundation is damp proofed) moisture can be absorbed and subsquently transfer to the framing.
make sure to properly fasten your sill plate to the the concrete. I use quick bolts to do so, and simply wire nail or you can tapcon the side framing. when you size your openning that you will cut out. plan and account for the trim you will be using. you will want to the trim overlap the concrete rather the have it end at the openning. this will allow you to seal the edge of your trim to the concrete. you will also have to deal with sealing the top of the window, which could have some different scenarios.
anyway, hope some of this helps.
View Image View Image
Edited 8/12/2007 12:22 pm by alrightythen
Thanks very much it does help. Perhaps I will post a picture of the results.