I need to frame a window into a brick wall. I'm not sure if I'm using the right terminology here, but I've already had a mason create the rough opening in the wall, install a lentil, etc., and I need to line the rough opening with the wood that will hold the window.

The sides of the opening are rough and somewhat uneven. My instinct would be to mix up a bit of mortar, smooth out the sides with a very thin coat so that they are flat, and then use masonry screws to attach the wood frame to the opening. That way, there will be no gaps between the masonry and the wood.

Does that sound right?

The other approach I could envision would be to first attach the frame with the screws, and then fill in any gaps between the wood and masonry with some sort of stucco or mortar mixture.

Thanks,

Chris

 

I vote for idea #2. However, there is a mortar mix that comes in a tube. Use a caulking gun to apply it.

 

I would probably take a scrap piece of wood, the width of the frame, to see how bad the concrete finish is.
If it's not tooo bad all around, I go with #2 and caulk the gaps.
If its really bad, I'd go with #1.
You still will caulk in either case. Just a question of how much.
You may want to use sill gasket to wrap the concrete where the frame will sit against.

 

my sentiments as well , silicon caulk

 

Im not sure about silicone caulking just yet. Depends on what trim is needed. Unless 1 is using 'paintable' silicone...regular silicone and paint dont match.
I would probably use the regular Dap Painters caulking..for windows and trim etal.
All depends again, on what trim is being applied .. either 1/4 round ..or if the window meets the edge of the wall, then probably casings of some patern.. either 356 or 653..or whatever you're using, to trim out the window.
Just my $.02cent worth.

 

I'm not sure you've provided enough information to give an educated reply. What sort of window is going into the opening... does it have a nailing fin, or a wooden brickmould and sloped sill? Or are you putting in a vinyl replacement window that doesn't have a nailing fin?

Usually the brick opening will be about 4 1/4" wider and 3 1/2" taller than the exact measurement of a window with nailing flange. This allows 2 1/8" on the left, right and top sides for 2" brickmould trim and 1 1/2" on bottom for a sloped 1 1/4" sill.

If your window already has a wood sill and brickmould attached, the masonry opening should be sized about 1/4" wider and taller than the window's outside dimensions so that the window can be squared up in the masonry opening.

The "rough opening" in your framed walls would be sized according to your window size, and it does not extend out onto the brick.

There is always a 1" space between the exterior of the sheathing and the back side of the brick, so sealing the "gap" you refer to, is also a moot point. Exterior window trim (which is often installed AFTER the window is in) covers this gap and the perimeter of this trim is sealed to the brick in order to keep out the majority of water. If your brick facade is correctly constructed, #30 felt is behind the brick to protect the sheathing and weep holes are located near the bottom course of brick to allow drying of the 1" air space to the outside.

And please don't use silicone on brick.

 

Excellent feedback... a mouthful, but still pertinent to this install.
More info needs to be determined.