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The Roof Part Two -- 7 November 2010 -- I've been grabbing every bit of dry weather to get this job done before winter. This photo is a detail of something I did on my previous quick trip, putting scrap plywood on the ends of the long boards that stick out on the sides of the structure. That white thing is one of my ghetto dehumidifiers: a sock filled with crystal cat litter. The pearls are better than the sharp-edged crystals, because they have less dust. The material is silica sand, the same thing they use for the tiny dehumidifiers in pill bottles. It sucks up moisture, and you can recharge it by sticking it in the oven at 240 degrees. Anyway, when I put the tarp on, I filled five socks and stapled them to the roof, to reduce condensation under the tarp. And on the latest trip, I took them off to put on the tar paper.

Roofing "felt" is actually thick paper saturated with asphalt. I'm using #30, also called 30-pound, which is the thicker kind. It comes in three foot wide rolls, so to cover 13½ feet from top to bottom, I used five courses, going side to side across the roof, with 3½ inch overlaps calculated to leave a few inches on the top and bottom. Here is a closer photo of the felt with lines that I drew to mark the locations of the boards under the plywood (in pale green) and the edges of the plywood (in orange, or if you're colorblind, they're the dim perpendicular lines). The white lines came already on the paper, to help lay it parallel. I was marking the boards so that when I put the roofing on, I would know where to put the screws to get them anchored in the boards for extra strength; and I was marking the edges of the plywood to help put the metal on straight, and also to avoid driving the roofing screws into the deeper screws holding the plywood to the boards. For the lines I used crayons, which are much cheaper than grease pencils and have the advantage of coming in many colors. To attach the tar paper, I used a staple hammer and 3/8 inch staples.

The tar paper went on without a hitch. I got up there early Tuesday afternoon and had it all done, except some trimming, before bedtime. This time of year the days are very short. I get up at sunrise, see what work I can do before the frost thaws, then work all through the sunny part of the day. When the sun goes behind the trees, I start putting on layers of clothing and keep working until it's too dark to see what I'm doing. Overall, I still like it better than working in the summer, when midday is too hot to do anything and then the mosquitoes come.

On Wednesday, after the sun steamed the dew off the tar paper, I started putting on the roofing, and here you can see where it stood on Thursday morning. This is a locally-made roofing product called Loc-Rib. It's a brilliant idea: the screws go on one edge of the panel, and then the rib of the next panel snaps down and covers them from the weather. I started on the left side of the roof, with the short panel, which I made by cutting one of the long panels in half. Then I worked my way across. At first I was using an awl with a mallet to pound holes in the metal, then a hand drill to make pilot holes for the screws, then a battery-powered drill to drive the screws. Later I figured out that I could have just made a tiny hole with the awl and driven the screws straight in, but then, that might have drained the batteries faster and forced me to finish by hand.

On Thursday, ahead of schedule, I did another project, and then finished putting on the panels. The main thing left to do on Friday was trim the edges. This was harder than I thought! I was using good tinsnips, but the problem with using scissors to cut metal, is that it's damn hard to get the metal out of the way so you can get the tool in there to keep cutting. You have to do a lot of bending, and I eventually learned to think of it as tearing the metal, with the snips just helping it tear. Also, cutting the locked ribs was impossible. My family was coming up for a visit, so I asked them to bring hacksaw blades, and here you can see what it looked like half-done, with the flat parts cut away and the ribs waiting for the saw.

And here it is all attached and trimmed. Thanks Sean for helping with sawing and drilling. Even Loc-Rib needs some exposed screws, and you can see them around the edges. The hidden screws are pancake head, and the exposed ones are painted to match the roof, and have rubber washers to keep the water out.

So the hut is now adequate to survive the winter, but there are still a few things I'd like to get done on the next trip...


Building is Complicated -- 29 October 2010 -- This week it stopped raining for a day and I dashed up to finish putting plywood on the roof and rounding it off. Also I made this. I'm not sure what it's called, but the idea is that water hitting the edge of the roof structure on the high side will drizzle down into the building, so you have to make something like this to catch the water and drip it onto the ground.

Originally I was going to use a five foot piece of 2x8, and I bought the board and cut it, but before I attached it, I grabbed a piece of roofing and slid it on top to see how it would fit. I planned the metal to overhang the wood by an inch on the bottom of the roof and a half inch on the top, but at some point I made an error, and the span of wood was an inch too long. So I sawed an inch off the top edge and instead of the board, used scraps of plywood, which will probably work better anyway. I wanted the left side to match the right side, because it would look like the batman logo, but it didn't work out that way. This is made from four pieces, and the two in the middle are darker because they're left over from the outhouse job in 2007. They had been coated with linseed oil, and I gave the whole thing another coat. "Boiled" linseed oil, by the way, is not boiled, but mixed with toxic solvents. Linseed oil is flax seed oil, and now I use food grade flax oil that's past the expiration date, which can be bought at Grocery Outlet for roughly the same price as non-food grade raw linseed oil, if you can even find it.

The picture above has lots of information. You can see the walls, both parts of the door frame, the lintel, the center beams, and several of the wires holding stuff together. The beams are held to the lintel by nothing but gravity and wires, and the boards are held to the beams by screws, and also by wires all around the outside of the hut. I wanted to build a roof that would last 50 years, and there will be some very strong winds in the next 50 years. So every level of the roof has to be built to not be pulled up by air pressure. Of course, the whole thing might be ruined by frost heave because I didn't build the foundation deep enough. But one function of this structure is to find out what I can get away with.


The Roof Part One -- 24 October 2010 -- When people talk about natural or low-budget building, they talk almost exclusively about the walls. This is because the roof is more complex than the walls, there are more ways to mess it up, the consequences of messing it up are worse, and it's damn hard to make a roof that's natural and low-budget. It's like, "oooo, you can build this wonderful hand-made house and oh yeah you'll have to shell out thousands of dollars for industrial materials to keep it from getting ruined in the first rainstorm."

In the photo above you can see $100 in industrial materials that I bought at Home Depot and hauled up a couple weeks ago. It was not as hard as I expected to put fourteen foot boards in a six foot truck bed. To keep them from tipping or sliding out, they're bundled with twelve and ten foot boards, and then the whole thing is weighted down with five sheets of plywood, and just to be safe, on top of that I put a 50 pound bag of clay.

Before I knew what stuff to buy, I spent many hours doing sketches, and it's taken me years just to wrap my mind around roofing in general. But having done the mental work, the physical work is going faster than I expected. Here's the first layer, which I'm calling the beams. Since they slant downward, you could also call them "rafters". It was an ongoing project this summer to find four trees, living or dead, that were the right size and straight enough. The two center ones are fresh douglas-fir, I think the one on the right was standing dead on the north hill, and the one on the left was in a slash pile. I had the two center beams cobbed in and wired down on the previous Friday. On Monday I got the two edge beams placed and loosely cobbed in. Then came one of the tricky parts.

If you're building with all rustic materials, you can just slap them on top of each other and not worry about how they line up. But if any of your materials are manufactured with flat surfaces and 90 degree angles, then you have to build a bridge between the roiling chaos of Earth and the mechanical perfection of Heaven. On top of the curves, you have to make a square. I decided to transition to square between the center beams and the edge beams. The center beams had to fit around the positions of the window and door, so they are a bit skewed, kind of like this   //   and I had to place the two edge beams so that the four beams together would look like this   |//|

I did this by cutting the edge beams precisely to 132 inches, and placing boards across the ends, cut to 104 inches, making a rectangle. Then I pounded tiny nails into the top two corners, to hold the ends of two measuring tapes, and brought the tapes down in a big X to read them at the bottom corners. Then I kept sliding everything up and down and back and forth until the two cross-corner measurements were equal. Then I drilled holes and screwed the boards down, one corner at a time, continuing to measure and tap with a mallet. In this photo the screws have been placed, and you can see that the numbers are still a little off: one is 4272mm, and the other is nearly 4273mm. Seriously, that level of precision for this structure is ridiculous, but I was having fun!

And here you see the second layer of the roof, done on Wednesday and photographed (as always) on the following morning when the light is good. The cans of Amy's Curried Lentil soup mark the corners of the square. (It was easier than photoshopping in four arrows.) So all the other boards could be placed by measuring up or down the slope from those two boards. You might also notice that the edge beam on the right is propped up. That's one of the little imperfections that crept in: that beam was a bit low so I was trying to raise it and pack more cob under it, but I never was able to raise it enough, so the boards had to be bent down to screw into it. These boards are 2x4's, which are actually 1½ by 3½ inches. Originally I was going to put them up on edge, at 24 inch intervals, but Charlie convinced me that it would be much easier, and almost as strong, to lay them flat at 16 inch intervals. Then I made a few final tweaks, moving one board up a bit to fit around the window, and most of the rest one inch toward the top when I decided that was a better fit for the roof.

And here's the plywood over the boards, done on Thursday. At this stage the panels have been screwed down just enough to hold them in place. I decided to go with all screws, no nails, and I'm sure I didn't pick exactly the right kind of screws, but square drive screws are definitely better than phillips head screws, which were designed for machines, not humans. Also, I decided to go with plywood, not OSB. The cheapest plywood was almost double the price of the cheapest OSB, but it smelled like wood, where the OSB smelled like industrial chemicals.

If you look closely, you can see how I arranged the plywood. They say you should avoid having four corners meet at the same spot. So at top center, lower right, and lower left, are three full sheets. The bottom center sheet is a bit darker, and I cut two pieces off it with a Japanese hand saw. One of them is leaning against the side, and the other is placed at center right, which takes up enough room for the top left and top right panels to be cut from the same sheet, with one of them rotated making it look brighter.

On Friday I put a bunch more screws in the plywood, took a rest, and then did the most exciting part of the whole project. To round off the corners, I walked around the perimeter of the whole building, widdershins, holding up the chainsaw, while the falling pieces bounced off my helmet. Using the corners from the two bottom pieces, and the small rectangular piece, I believe I will be able to cover the long boards sticking out on the two sides.

Also on Thursday, the end of the last long dry spell of the year, I took down the wall tent and stuffed it in a steel drum. Then I slept in the structure. The inside area is roughly 50 square feet, enough for my old car seat mattress, a camp stove, and a few bags. I was going to call it a shed but now I feel like calling it a hut. There is more work to do, which again depends on the weather. The whole thing is now covered with a brand new 15x20 foot tarp, carefully attached so the rainwater doesn't run off onto the walls. And everything I need for the next few stages is already up there, in case we don't get another clear week until the roads are covered with snow and I have to walk in.


Lintel -- 16 October 2010 -- On this trip, using week-old cob that only needed some wetting and re-stomping, I built the walls around the door frame high enough to begin placing the roof beams. This photo shows something I've been thinking about, and when I got to this point, it became obvious. Mainly the lintel makes it much easier to place one of the beams. That piece of wood on top of the level is cut to the width of the window, which fits between the two center beams on the other side. So on this side, it marks the space between the beams, with one of them going to the right of the door frame, and the other going above the low side of the frame. Originally I was going to rest it on top of the sloping frame, which would raise two problems: how to hold it there, and how to get all the beams parallel and level, if one of them can't be moved side to side without also moving it up and down. The lintel solves both problems. Also it makes a platform to fill in the walls above the door.

Here you see some beams parallel and level. I love this kind of work! These pipes mark the locations of the beams, and I spent more than an hour fiddling with them, measuring the distance between them and lining them all up with my eye, until I could see all four positions and know how high to build the cob and wood under them. Also notice the wires, which are wrapped around wood buried in cob and will be wrapped around the beams.

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