Replacing a 20" x 32" basement window

Fox

This home has a single basement window. It seems to sit flush against the transition between the basement brick outer wall, and the wood of the first floor, whatever this point is called. From a horizontal cross section, it seems to sit between the outside mortar and the inside drywall.

This house was built in 1986, and from the construction of the single pane aluminum window (if you can really call it that) I assume it was installed when the house was built, as the trim around the window seems to be set into the mortar.

I picked up one of these in 32x19, though I'm starting to wonder if I can't chip away at the eventual rough opening to fit a 32x23 in there instead, rather than framing the new one.

My question: Do I just chip away at the mortar holding the existing aluminum framing to remove all of it, and try to make a frame and somehow attach the new vinyl window in the new hole, or just rip out the window and its tracks and use the existing framing to hold the new window? I'd have to put wood in as spacers regardless due to the size.

That probably sounds very confusing without pictures, so I'll try to get some up ASAP.
Edit: Pictures!


Thank you for any advice. Even answering how I should remove the old framing would help. I've a chisel and hammer ready to try it.

jomama45

It's hard to tell from the pics, but if the window is 3 full block high, you'll be able to fit the bigger window in.

As for removing the old, I'd start by chiseling awy at the mortar "wash" at the exterior (bottom). There is a good chance that the window is layed into the sidejambs via "sash" block, and will be somewhat dificult to remove. So, I'd start at the bottom of the frame, get rid of mortar & pry up the frame enough to cut it with a sawzall, grinder, etc..., then work to the sides doing the same thing.

Fox

I managed to start chiseling away at what I'm calling the 'frame': The metal exterior set into the mortar. I expected it to end at the indentation I could see, but it seems to go deeper. I may be forced to get a bigger window.

My neighbor got curious when he heard all the hammering and came over to investigate. He said his basement window was replaced by a contractor, and they started to do the same thing I am, before the foreman told him to just frame it within the existing frame. He said his new window is smaller as a result. I'm going to swing over and take a look.

My future father-in-law offered a circular saw with masonry blade to run alongside the window and cut down into the mortar. What are your thoughts on that? On one hand it seems dangerous, but I don't have access to a hammer drill and it would certainly make this faster if I go the route of cutting away all the mortar.

I looked at the outside again. I thought this was standard concrete blocks, but it seems to be brick. I can't yet figure if that's just a facade due to the mortar. I looked up a "sash" block, and I certainly hope that isn't the case!

Thanks greatly for all the advice. I do have a question for you, as you seem to know masonry: should I back off of this project having no experience with masonry? I'm rather industrious and learn quickly, but this is a field I've never entered before, and I'm beginning to question how I'm going to secure the new window to masonry, as I was originally going to use construction caulking and expanding foam after shimming it into place. This one was mortared into place, and I'm wondering if my method will hold a vinyl window where it should stay?