How to handle my old custom fixed windows during my exterior insulation + siding install
Hi again,
I’m continuing my exterior 2″ mineral wool + hardie siding install on my cabin. I’ve take off all my exterior siding and started to use the Prosoco products for air sealing and flashing.
We had windows installed last November which have the proper window buck sizing on them.
Then I realized, we have these custom fixed windows and said to myself, “well how do I approach this?!”
See pictures for example. All I’ve done so far is flashed what I can with Prosoco’s Fast Flash. You can see in the pictures that the windows sit directly on the wood sill frame. All I have to follow is an old Fines Home Building article https://www.finehomebuilding.com/1981/09/01/installing-fixed-windows
Is there anything else a bit updated? How should I approach this?
Thanks,
Zach
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Replies
Looks like the post stick out far enough so can't you just add or box it in with some 1 x6 or 8 depending on how far out the insulation will be....
Tom,
I plan on removing the current 1x4's that are currently holding the window in place (see picture, labeled A) and also then securing with a trim piece (labeled B in picture). What I need help on are the details (see second picture). First, I will add furring around the window (inside of rough opening or guessing this should be done on top of the plywood sheathing equal to my insulation + rain screen). Then since I'm not removing the window, do I custom bend a piece of alumnium flashing on bottom part of window, butted up against window, then use a bead of caulk or fast flash on top of aluminum flashing so water doesn't get underneath it? Then add same bead of caulk to parameter of window and secure in place with proper length 1x's and trim on top?
Yup, that should work, just figured wood trim with appropriate flashing as an option in case you ever wanted to paint it if you ever changed your color scheme...extending the wood further out on top would/ might give you a little more of a drip edge to keep water from dripping on the sill.
Generally you want some way of draining condensation from the bottom of the window. So this means the aluminum sill should run to the INSIDE and the caulk holding the window in place should have a couple of 1/2" gaps along the bottom to allow for drinage. Not sure if this is possible now. Make sure the new lower trim won't trap water, it should be well sealed to the glass or gap it to allow for the water to flow down to the aluminum sill bellow.
For the windows lower down the wall, you want to install a head flashing just above the trim extension to channel water from your new WRB out past the trim.
I totally agree Akos. This is the main reason why I'm posting this question. Basically I really don't believe I'll be able to get the aluminum flashing underneath the window unless I plan to remove the windows, which due to their size and height, I don't plan on it. Is there a next best plan of attack/recommendation here?
I've also posted a pic mock up of my window. Can you comment on this? Maybe I only have the window furring then the aluminum flashing on top of that? How should I fasten the aluminum flashing here if it can't be slide underneath the window? Use liquid nails? Would the same go if I used a trim board instead of the aluminum flashing?
Thanks.