School of Hard Knocks, Lesson Number 679

Lesson Number 679: Just because you've hired something out to a professional in no way removes the responsibility of due-diligence from you. Things will always go better if you know what should or should not be done.

Case and point, the thing in my living room as of Monday this week.

First and foremost, I would like to make clear that I have no malicious intent towards our heating and air guy. He works on new construction and not old houses. Overall, he did a good job (we'll know for sure when the electrician wires the baby up). The box in the living room is my fault. If I had done my resesrch, asked the right questions, and made my wishes crystal clear, the box that should not be would not be.

Functionally, we have a working heating and air system. Aesthetically, it's a damn stinker. Everything that he told me about the return air vent's placement was true. I crawled around under the house with a tape measure. It is impossible to install the return air vent in the location of our choice. Really, it's a no-brainer. Two bodies can not occupy the same space in the quaint little world we live in. There is no other centrally located spot in the Queen to put a return 24" x 24" air vent except where he put it.

Later, I started wondering if a 24" square vent was the only type of vent that would work. I checked online and quickly found there are all sorts of return air registers.



If you decide to install four 10" x 14" return air vents in the hall floor and move a cold water line, you'll find that you have more options. Four 10" x 14" return vents have a total of 560 square inches of space which compares well with the 24" x 24" vent's 576 square inches. Our heat & air guy said he oversized our return air vent a little, so I think going sixteen inches smaller is okay.

As I understand it, a return air vent has to be a certain minimum size to allow adequate air flow back to your unit. If it is too small, the unit has to pull harder, wears the equipment down, costs more, and shortens the unit's lifespan.

So, I figured, what the hell. If their little chipboard box was adequate for the system, why wouldn't one I built?

I took yesterday and most of Monday off. I just couldn't stand knowing that box was in my living room. It bothered me like a stick in my eye.

First, I demolished the chipboard turd in the living room and detached the return duct from the floor of the house. It was a quick, easy, and highly gratifying job.

Then, I spent the rest of the time under the house building my own return air box. My hands look like I spent two days wrestling a cactus. Sheet metal and fiberglass are great. I tried to take some pictures but they didn't turn out. Here is a crude diagram of it.



The box I've built is larger than the one gracing my living room. The main body of the box is approximately 38" wide, 27" tall, and 40" long. There is a second section that is like a glorified duct that is 38" wide and 48 inches long that attaches to the top side of the main box.

The box extends up between the joists to the sub-flooring. I've used cans of spray foam insulation (normally used around door & window rough-ins and where pipes & wires enter the home) to seal the joints, nooks, and what-not to keep air (and bugs) from the crawlspace out of the return. Once the box is completed, I'll probably enclose it in ridged, insulation foam-board for a good measure.

The blue diagonal line across the box's interior is where I'm going to build an internal partition to mount the air filter. I wish I could find a more convenient place for the filter. I don't much relish having to crawl around under the Queen every time the filter needs to be changed, but life is full of trade-offs. I'd rather crawl under the house than look at that damn box.

I hope that I'm as clever as it think I am and this works. Wish me luck.