Rain gonna stop me from building stuff? Nope. It does slow me down a bit, though.
Without ever trying to cut one, I simply assumed compound angles would be hard to get right. Today I tried to cut one. Well, four, actually. Well, really eight. This was one of those times that assumptions turned out to be 100% correct. Compound angles are hard to get right. One does not simply set the miter and bevel and bring down the chop saw. One affects the other.
I did not do a very good job on my compound angles but I did accomplish the fit I needed to accomplish and once the thing is all buttoned up, nobody will ever see how badly I did the compound angles. So in that sense, they are definitely “good enough” though they are indeed a very long way from perfect.
What, you might ask, would require compound angles? I’m glad you asked! The roof rafters of this thing does. (Please ignore the hastily attached zip board acting as a rain shield – a cut-to-fit one will be installed later. I was done for the day and needed to keep the deck from getting soaked). Where is the compound angle? Well, there’s the 13 degree pitch of the roof and a 25 degree toe. The outside rafters follow that 25 degree toe AND must meet the body of the house and the front of the box at 13 degrees off vertical. It took several tries to get it to even *fit* let alone fit well (which it still doesn’t, but it is indeed good enough to be structural, so that’s good enough).
I do not actually expect there to be *any* other compound angles in the whole project, so there is no pressing need to learn to do them properly. Still, I am curious how it’s done in practice. People build shapes like these all the time and they fit ok. It’s clearly possible.
So, what goes in this box? I affectionately call this the “shedlet”. It is where the propane tanks will go. Originally, I had intended two 100-pound (capacity) tanks would go here. The height of the bathroom window (that’s the one you see here) was chosen such that it would be just above the roof line (as built) allowing for such tanks, which are 48″ high, to stand and be sheltered without obstructing the view. It was such a lovely idea, all full of forethought!
And then I went about building the deck for the shedlet and realized that there was no way it would be satisfactorily attached to the tongue of the trailer chassis without some side rails, similar to how the rest of the house is built. Ok, no problem. Side rails added (shown as lowest horizontal features).
Then I tried to lay out the floor. When I did, I realized that even with the side rails, If I laid out the floor in any sensible way, there was no way to secure it directly to yonder side rails. It was as if you were to take your hands, hold them vertically to karate-chop, then make an X with them, pinky crossing thumb of the other hand. They are on top of each other, yes, but fastening one to the other so that it would be held down and would not move is not obvious at all. Sure, there are corner brackets and all manner of oddball hardware one could use, but most of them, frankly, are designed for larger systems than this. A bracket that would fit in here would have like a single #8 screw in each member. I’m not building my house that way and the close quarters preclude using tools to drive those screws anyway. Non-starter, as far as I’m concerned.
Okay, play B. Build a sub-structure which can mate naturally with the side rails AND with the deck. that’s the second level of lumber you see — only the ends are visible from this angle. This worked well. They affixed easily to the side rails and spanned the space. You’ll notice they are oriented parallel to the ground/deck. This was essential for getting them to affix easily to the rails and what’s above them. However, it is also their least capable orientation for load-bearing. I pushed on ’em. Nope – not suitable for holding 340# (empty tank is 70#, so 170# each when full) long-term. I was sure they would bow. The span across the space is 53 inches. That’s a long span for a 1.5″ thick piece of wood. Or even three of them. Shit. Okay. Plan C.
Plan C is to build the floor for the deck the ordinary way, like a wall, where there’s two ends (instead of head and foot), studs nailed through the ends, oriented with the longer dimension perpendicular to the load bearing surface (short face parallel to the ground). The foot is then nailed to the side of the building like a ledger board. Presto. Framing that can take a deck and bear some weight. But aside from a few nails against the house, what keeps it there? Yeah, good question. It is also screwed from the bottom through those horizontal boards, into the joists just built for the deck. They, in turn, are screwed into the side rails and, for that matter, the metal chassis itself. And that’s why they had to be there – not to support the deck, per se (they’d bow) but to provide a means by which the joists, which are in totally the wrong orientation to be affixed to anything horizontal from above, can be affixed to something horizontal from below (now that there’s something below them through which screws may be driven upward into them).
Now add some stout 3/4″ plywood, nail that down with ring shank roofing nails, and you’ve got a mighty stout deck, indeed, that is going absolutely NOWHERE, even when subjected to winds and highway travel. And it will hold 340 pounds forever, no problem. I’m certain of that.
Except.
Except now the deck is 1.5 inches taller than I thought it would be, due to those horizontal members. Also, when I considered the height of those 100# tanks, I am sure I failed to factor in a little bit of headroom for getting the tanks loaded and unloaded from here, not to mention the thickness of the roof system (at least 3″ of wood, plus whatever goes on top of the roof deck, such as some corrugated metal). So now I have 5 inches I’m sure I didn’t account for and I probably failed to consider the floor system thickness, too — I bet I just measured directly to the plane of the top of the chassis when contemplating that window. Ooops.
When I add it all up, 48″ from the actual top of the floor deck, as built, factor in 4″ inches of roof system, suddenly the roof now intersects the window. SHIT. And that doesn’t even allow for some maneurvering headroom, which would definitely be needed. Oops.
Okay, then! No 100# tanks for me! In retrospect, that’s probably a good idea, actually. Who wants to lift a 170 pound tank (when full) 2.5 feet off the ground and manhandle it into place? Not on my best day.
The next smaller standard tank is 40# capacity and 30# empty = 70# full. Only 30 inches high. That fits. And I can lift them easily when full. And they are smaller in diameter as well as height, so maybe more than two can fit in there? Yes, actually. I’m sure three will fit — possibly four (I need to lay out a circular template to check).
Okay, then, maybe I get 160# of capacity instead of 200 but I also don’t break my back or obstruct my window. That’ll do.
Next question: how fast will I consume the propane? Is 160# a lot for this house, or is it just a week’s worth? Honestly, I have NO IDEA AT ALL. I can do a little guessing, though. A pound of propane, according to the interwebz, represents about 21,000 BTU. I was looking at a propane heater that consumes about that in an hour. So a pound of propane is an hour of heat. . . which sounds like it will get used up right quick. Until you realize that after the spray foam people do their thing, this little homebox will hold heat really quite well, I expect. I would be surprised if that heater was on for more than 10 minutes per hour, even on a cold day. So a pound of propane in that case is 6 hours of heating duty. 4 pounds a day. Minus some for cooking and water heating, call it a month’s supply in the coldest part of winter, much more when it’s warmer? I dunno. Maybe less. Maybe a lot more? It depends on so many factors and I have NO DATA. But if a load of propane lasts a month, I’d be okay with that. That would be a reasonable replenishment schedule. And it doesn’t count the contribution of the wood stove for heating… but that’s okay, this is total bullshit numbers land anyway 🙃.