Encasing the HVAC


Basement, Blog, Home, Woodworking / Wednesday, September 26th, 2018

As Ellie and I speed up on our project of finishing the basement of our house, we’ve broken the process down into bite-sized chunks to help us keep moving forward. The small projects were written in the order they need to be done, so we don’t end up getting ahead of ourselves. While writing out the list, we nearly forgot about putting down the flooring! The list grew and grew as we wrote it, always remembering that there was one more piece to take care of. 

The next project on the list was to build a case around the HVAC in the basement, so we could cover it up with drywall like we plan to do for the rest of the ceiling. In its essence, this is a fairly simple and straightforward project. However, as we looked a little deeper, things weren’t as simple as they seemed while sitting at out kitchen table writing a list.

The HVAC hang beneath the floor joists and we had no intention of moving up, if that was even possible. It runs roughly the length of the basement with offshoots to the exterior walls and upwards. These offshoots, fortunately, are nestled between the ceiling joists. Only the one main line needed to be encased.

Basement HVAC Casing Beginning

What I figured we would do would be to drop a vertical stud along either side of the HVAC at each joist. It would hang just below the HVAC line. Then, I would tie them together with another stud. These pieces will later be tied together with sheets of drywall.

For the most part, that’s what happened. I cut a couple dozen uprights at 19 inches each and 13 cross-pieces at 26.5 inches each. The 19 inches was just enough length that I could butt them up against the floor and they would hang down low enough. On one side, I could also press them up against the I-beam that ran the length of the house, guaranteeing I had a side that was square. For the other side of the HVAC, I created a couple spacer jigs to keep my spacing consistent. I needed more than one because the HVAC narrows at one point. After the uprights were installed, I connected them with the cross-pieces. It wasn’t smooth sailing.

Basement HVAC Casing Uprights

The first problem I ran into was that above the I-beam, two joists were joined together. So when I tried putting the uprights on the same side of the joist, things didn’t line up. The simple fix was to have the left side uprights on one side of the joist, and the right side ones would be on the opposite side of the joist.

The second problem I ran into is a legacy one. When Ellie and I hung the drywall, we didn’t compensate for the fact that the studs were placed at random intervals. For the most part, the seams won’t be an issue because they line up nicely and there is the foam board insulation behind the drywall to prevent too much moving. However, a couple seams we could not get to sit flush with each other. One of which was at the end of the HVAC. I figured I needed to fix this before moving forward. To do so, I pulled off the drywall, cut a space in the insulation for a new stud, drilled holes in the foundation to screw the stud into, and then refitted the drywall. If you’ve never had to put a hole in your foundation, don’t. It’s terrifying. But now that it’s done, the seam sits much more flush than it did before.

The third problem I ran into was at the other end of the HVAC. This is also where the door into the other half of the basement is located. When they built the wall with the door in it, I don’t think they thought ahead to what they would do about the HVAC other aspects of finishing the basement because there is very little clearance to install the casing studs and cover it in drywall. Ellie and I looked at it and decided to use a narrower piece of wood to build the end cap casing, which should allow just enough clearance to open and close the door without it scraping the ceiling. As a result, the drywall will be at a slight angle in that spot compared to the rest of the casing. But what can you do?

Basement HVAC Casing Mostly Done

Then there were a few other places where things just didn’t line up and we went for a good enough because this casing is just meant to hold the rest. As long as the drywall doesn’t look terrible , then no one will really know what’s going on underneath. There’s one spot, as well, where there’s a vent in the HVAC and a cross-piece runs right across the vent. We’re just going to leave the cross-piece off. It shouldn’t be needed and again, no one will notice once it’s all finished.

In the grand scheme of the basement finishing project, this was but a small bite. Somehow, the small bite has had a dramatic effect on the basement. It really looks like it’s moving along now. Maybe, for the first time in a while, it’s because there’s a noticeable change when you come down the stairs. I’m still not used to there being studs hanging from the ceiling. Hopefully I keep moving at a good enough pace that everything just comes together and before you know it, we have a finished basement. Hopefully.

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