Window Replacement – Getting the Size Right

Whelp, fall showed up this week. And remember how I never finished spray foaming the windows? Well, Tito was watching TV and said, “Babe, these windows are drafty!” So I had to fix that STAT. And light the boiler. Thankfully, this year started differently than past ones in that the heat works and making it work didn’t cost me anything.

Back to the window size, it was a finicky issue because (1) my window openings are old fashioned and not normal and as it turns out not even square (2) I got really picky about making it all perfect even though (3) I couldn’t actually see the framing I was working with until I started ripping apart the old windows. So I did all my figuring just from observations and counted on the idea that the size would be perfect once everything went together. There’s one original window left on the block. This is what I was trying to match everything to.

What you can see here is that just behind the brick mold there’s a chunky piece of trim that’s rounded off on the end. This is the sash stop. The flat part right against the brick mold is the flat frame reveal. And the lower sash closes directly onto a chunky wood sill.

My windows have a second sill on top of the original. I looked into eliminating this but that wasn’t possible. And the sash stop is way thinner and squared-off, which I only noticed after the windows were installed. Not that I could have done anything about it anyway. At least the windows I got have a flat frame and I could put the brick mold back in the original way on top. (I’m going to caulk that big gap below the window and make it pretty.)

And you see that my flat frame reveal is CLOSE to even all the way around. I was obsessive about this. Before I took down the brick mold, I measured its inside opening, figuring that I would size the windows to mount the molding right where Marvin intends it to be mounted and then obsessively center the windows in their openings. This is not the normal way to measure for new windows, but Marvin has section details open for anyone to view. Here’s the detail marked up with some colors to help you see it. Of course my original brick mold is much narrower and deeper than the standard-issue stuff shown here, and the original sills/subsills are like 3 times as thick. But you get the idea.

Basically, we can see here that the opening in the brick mold is 11/16″ in from the outside of the frame all the way around. I rounded this off at 3/4″ and had a window size that was a round number. The flat frame reveal, marked in red, is not actually dimensioned, but it’s about an inch.

So. It’s chilly. But not freezing cold yet. That means that I can still safely try to get rid of those white stains next weekend. And it looks like weather this week might cooperate to FINALLY finish prepping wood trim. You may have noticed that I started the window sills already even though the weahter wasn’t quite ideal. The wood filler still cured just fine. I’m hoping to wrap up wood filling AND brick cleaning soon though. I might even burn another vacation day to do it.