The drawings for these notes are underscaled for a 20 foot lodge and shouldn't be used as a guide in any case. Take your measurements from the people in the group, the most important being the vertical clearance of the ledge's backrest to give good headroom for sitting.
To get a sense of the scale of this space, see the photo opposite. And pace off ten feet on the floor. It is a pretty big circle, there, in the lower pit. These dimensions describe a structure almost exactly as detailed by Ishi. He said this dwelling was used by a couple with children, sometimes with a grandmother and grandfather. He said they lived, cooked, ate and slept there. The Indian Tales book describes alot of outdoor living and sleeping as well.
ORIENTING THE VENT WITH THE WIND
Prevailing winds are generally from the west, so the west side of a dwelling is the windward side and the east side is the downwind or lee side. Of the five structures described by C. Hart Merriam, three face the vent to the east, one to the north, one to the south, but none face directly west toward the wind. It could be that the north and southfacing structures are following a rule about prevailing winds which could vary due to terrain. I assume that it would be disruptive to have wind flowing directly down the vent. "The Indian Tipi" by the Laubins directs the reader to face the door of the tipi to the east partly because it is the lee side of the structure. Ishi does not mention orientation, nor does Indian Tales. Both the tipi we made earlier and our lodge had the door and vent to the east and it worked beautifully.
ANGLE OF RIDGE POLE
Note that the ridge pole in the "Indian Tales" drawing is not steeply pitched. (See drawings opposite page 2.) This makes a more stabile resting place for rafters, which otherwise don't stay put during construction. Also, the mild slope is a more natural hill shape.
[what about put the photos here? if so, photo 10]
CREW SIZE AND TIME
Eleven Berkeley high school students and two leaders took six days to complete the lodge. (See photo 10 and photo 11). We are sitting in the unfinished lower pit. The ledge behind us is at ground level (the mistake). The mound of loose earth areound the ledge is dirt from the lower pit. If we had sunk both pit levels below ground it might have taken us four or five days to finish.
Ph 11 (?)
NOTCHING THE RIDGE POLE
The Center Post is notched to accept the Ridge Pole.
The Ridge Pole gets a lengthwise notch at the tip, to accept the Center End Pole at the west end of the lodge.
And the squaredoff tip of the Center End Pole is cut down to allow room for the ribs that cross over the top of the Center Post. (See photo 13 and photo 14.)
SMOKE HOLE DETAIL
The first, central, rib that borders the west side of the smoke hole has extra duty. It should not be notched for the smoke hole cross piece. If it has to be notched it should be doubled up. Otherwise, the cross piece can be supported by leaving a branch stub at that point of the rib.
Note second beam for smoke hole
End view of ridge pole
A single beam is enough if it is not notched for the smoke hole cross piece.
Beam is weakened if notched for smoke hole
Beam braced with branch support is stronger
DEPTH OF SOIL COVER
Don't know where I got 4 or 5 inches. The Ishi notes say, "...banked with dirt to a distance of 3 or 4 feet for added warmth." I would think that 3 or 4 feet of earth on top would cave the roof in. The work "banked" sounds more like they are talking about buttressiing from the side, sort of like the picture in "Indian Tales" which is largely above ground with heavy side walls of earth.
Copyright 2002, Don Cochrane