Back Basement Window

The most complicated window installation was the one at the back of the house. The side and bay windows are fairly narrow and the top of the window is at the top of the basement, meaning there are no bricks above the window since the rest of the house is frame. The back window in the basement is over five feet wide but it’s short, with two courses of bricks above it. I was able to remove the existing window buck without the bricks above falling, but redoing the upper brick and installing a steel lintel seemed like the smart way to go. The existing window opening also didn’t have a sill, maybe because it used to be covered by the porch. I wanted to add a sill so that rain water would drip clear of the brick, preventing damage.

Removing the upper courses was a challenge because I didn’t want them to fall on me, so I wound up sitting on the new retaining wall and prying them loose (as seen in the video above). As expected they came down a dozen or two at a time, so it was a warranted precaution. I decided to go ahead and remove the second course as well, also captured on video. Once I removed everything and was down to good brick, I started with the lintel and upper bricks instead of the bottom so I could still put weight on the bottom as I worked. I bought and painted three six foot pieces of “angle iron” L-shaped steel. Our basement wall is three bricks thick (multi-wythe) so without getting a special piece of steel this was the easiest way to do it. I anchored the lintels in with brick and mortar on each side and then put in the middle course first, then the outside and finally the inside.

The next day I put together the sill, rebuilding the damaged courses and installing the limestone sill. I forgot to center the sill under the window, so it’s not perfectly symmetrical by a couple inches, but I can live with it. Then I rebuilt the sides where the center wythe of brick had erroded. Unfortunately I still wound up having to grind the sides to get it flat enough to fit the bucks. Since I bought my windows months ago with little to no clearance, I needed the rough openings to be big enough, which meant the sides had to be perfectly flat. On the side windows I did a lot of trial and error with test fitting the buck, but by this point I’d realized I could use my laser level to cast a vertical exactly where I wanted it, then grind away the red line.

Once the sides were smooth I installed the bucks the same way I did the side windows: pressure treated boards (though I increased to 2x10s in this case) with sill gasket installed using Tapcon screws. With the buck in place I slid the window into place, shimmed it on either side, and screwed it in with vinyl window screws. 

In the photo I took there were some shims underneath, but those were removed. On a horizontal slider you want it to rest on the sill. The final steps are sealing: backer rod, caulk, and spray foam. Once the pressure treated wood has properly dried (next summer) I’ll come back and paint the bucks. I plan to eventually clad the bucks on the outside with PVC trim boards, which will further protect the wood and make it look nice.