"Secret" Project Revealed!

Not a huge secret, but I finally decided that I've had enough of stepping on that awful grate across the Office door's threshold, so I've decided to do the necessary work to finish the duct work.

As many of you might know, a few months ago I was in Ottawa, and I found an antiques salvage store that carried some heating grates identical to the one in my living room. As far as I can tell, the house only ever had ONE of these wall grates, which I find odd, and I thought it would be fun to add a second one.

I had originally bought the grate in hopes of using it, or possibly just to replace the existing one, which is missing the lever handle for the internal batten. Since I bought it, I've had it sitting at the foot of my computer "desk" (a temporary card table, which I'm sure made an appearance in the Office floor demo post a while back), and I thought it would work well there.

I started the work by cutting and installing some structural braces and floor supports that will carry the weight of the floor patch for the old vent hole (no photos yet). The floor patching/repair isn't done yet, but it will be soon.

The next day, I started to work on the actual vent location and construction. I think I cut the hole in the wall and the floor on "day 2" and did the rest yesterday (day 3), but regardless, let's jump into it.

Note: I don't really understand the logic with how the house was built, with regard to how they did the ventilation. The first floor's floor is made up of old barn wood boards laid diagonally across large "tree trunk" beams spaced every 3 feet. The barn wood is not all the same thickness, but most is around 1" to 1 1/8" thick, and the spacing is also uneven (many boards have raw edges). Over this, there's a layer of thin cardboard, and then the hardwood. That's it. But the odd part is when it comes to the ventilation. They just cut large holes anywhere they needed. What's odd about this, is that since the "sub floor" barn boards lay diagonally, once they're cut, they aren't supported by anything. The only thing that holds them in place are the nails from the hardwood over it. But they did this everywhere, and it was like this originally. All the original main-floor vents are 12x15 (with the exception of one 14x18 - which is the one I'm covering over in the office door), and they're all the same. In a few places, I added some supports, but for the most part (and a bit surprisingly), it's all very solid.

Step one was to find the best spot for the vent. I knew where I wanted it, but I didn't know exactly where the electrical wiring passed, since there's a light switch on this wall just above the vent location.

I drilled a bunch of 1" holes in the drywall, and felt around for the wire. I didn't see it. I then drilled a hole at the top of the vent hole, and also couldn't find the wire. I was pretty sure I wouldn't run into the wire, so I just went and cut the hole. The hole needed to start at a 2x4, and end up with solid on all 3 sides.



Those of you who visit frequently might recognize this as the "hallway wall" in the Office. For my vent, I was basing my measurements partially from my original vent/duct opening in the living room, and partially off the vent itself. I needed a hole about 11" high, and 12 1/2" wide. After the hole was cut, I could see that the electrical wire was about 4-5" higher than my hole, which was just perfect.

Next was cutting the bottom stud, and the floor. Kinda scary, but also kind of fun. If you're doing this in your home, make sure you have clearance below (you don't want to end up cutting your hole over a joist, though a pipe, or into a wire). In my case, my finished hole was going to land about 8-10" away from one of the log beams, and in a spot clear from wires and pipes.

In this next photo, you can see the old duct that was still in use, feeding the old floor grate to the left. It was going to be gone/moved to feed this new duct.



I'll also point out that you need the right tool to do this kind of work. This was done almost entirely with my Rockwell Multi-Tool (They call it the "SoniCrafter"). Best 130$ I've spent so far. I'm not getting paid to promote them, but it's a damned good product. The first experience with this type of tool I had, was through work (but we use a 600$ Fein version). I find the Rockwell to be as good as the Fein, which is surprising considering the price difference. We use it all the time on installations, to cut wood trim in odd places, for outlet holes in cabinets, drywall, etc. The blades can also be resharpened rather than simply replaced. New blades are about 15-20$, but a local company can sharpen them for around 8$, and then they are as good as new. I've cut through plywoods, hardwood (this birch floor is very hard), MDF, drywall, PVC, and all kinds of stuff, and they last quite a long time, but I'm getting side tracked.

Once I had my hole ready, I made a pattern for the duct work box. I am pretty sure that new ducts for these super OLD vents aren't available, and since I can make one for free, I went that route. I'm sure that there are many tinsmiths who make custom duct work, that can easily throw one of these together for you ($$$), but here's how I did mine.

For the most part it's just a simple box with a small slanted front. You need to make sure to make the box a tiny bit smaller than your opening (or it will NOT fit), and you also need to make sure it will stick-out low enough under the floor (to hook-up your duct work). Another consideration you need to take into account, is how you'll be hooking it into your HVAC system. Will the duct connect from the front, back, side, or bottom. What angle is best? Etc.

For mine, I wanted to try to have the final duct running near the log beam, in a straight line, so I wanted my duct hooked into the back. I have about 4 huge boxes full of scraps and duct fittings, and I found one that worked perfectly.

I decided to make a full sized paper template for this duct, because it was a complex shape.



The paper template proved to be very useful, since I had already goofed a piece on it. I actually had measured the bottom wrong. I made it 4 1/2" wide (the same size as the top), and it should have been 5 1/2" (this was easily fixed on the tin copy).





Since I was making this for free, I used only the available scraps of tin that I had laying around. The main sheet (a flattened-out 5" round duct) could only accommodate the central part of my duct box, so the two side pieces had to be made and attached separately.



Tools needed for this:

- Ruler
- Sharpie
- Framing Square (large)
- Awl, screw driver, or another tool to score the tin
- Tin snips or shears (basically these are metal-cutting scissors)
- GLOVES (strongly recommended but not required, though there's a very good chance you'll cut yourself)
- Wooden blocks with good square corners/edges (to use for bending the tin)
- Pop-rivets & rivet tool
- Drill (for rivet holes you need 1/8" bit)
- Hammer
- Foil duct tape

Optional: First Aid Kit (seriously, if you're not careful you can wind up with deep cuts) I didn't use gloves this time, and only ended up with two tiny scratches, but be careful. The edges will be razor sharp.

Start with drawing and measuring out your main shape. Be sure to leave tabs along the edges (1 inch is a good size), and also leave allowances to have a folded-over seam on the exposed finished edges (since these will be sticking out of the wall).

Cut out the shape, being careful not to crinkle or buckle the tin as you cut. Cut tapers on all the tab corners. Here you can see the front, bottom, back, and top of the box, with a fold-over seam at the front and top of the box (both ends of the sheet), and tabs along all the edges.



At this point, you can start by scoring, and folding-over the good edges, and then starting to bend your edge tabs (at 90 degrees). If you have an opening to do in the tin, cut it before you get too far.

Openings are always a total bitch to cut. Unless you have a special tool, you'll just have to be patient, and do your best. I started the opening, by poking a row of holes through the tin with the awl, and then sneaking-in my shears.





Pretty soon, your box will be starting to take shape.



To attach the sides, I used a combination of 6 rivets (hammered-down flat after installing them with the tool), and foil tape. If you prefer, you can use sheet metal screws, but since this is a vent box that I might want to reach-in and clean occasionally (or if something falls into it), I didn't want sharp metal screw tips in there.

I did use two screws, however, to attach the "factory" duct boot to my opening flaps, but I only used 2 screws.





The finished duct is held in place with flat roofing nails. I used 4 (one per side, one on top, and one into the floor at the front edge). I didn't take any photos of it, but a stud was added to the right side, and to the top around the inside of the opening. The drywall around the hole was secured with extra drywall screws.





From the basement, it looks pretty awesome now.



You'll note that I didn't add any floor supports (in reference to the "note" earlier), but I did nail the sub floor up into the wall studs on each side, and I added some screws from the bottom up into the hardwood, so it should be just fine.

You can see a lot of the repaired/improved ducts here. The large box over the stairs is the hallway's cold air vent, next to it, a vent to the "L Room", then the new duct for the new wall grate (you can see the new box in the top left), and the last duct is the other "L Room" vent.




Side note, this was the Office duct work "before":



And here's a "before" of the photo above. What a mess. I've actually gained a lot of head room with my repairs.