Hexayurt construction
Introduction
This article is intended to provide a detailed description of the construction of the hexayurt so that the successes can be replicated and the few mistakes can be avoided.
The design applied at Factor E Farm as the Paul Newman Center for Temporary Housing (kind of kidding... Rob, call it what you like) was a perfect hexagon with 6' walls, 10' peak, and 14' foot width. It will comfortably house 3-4 people and should last about 10 years, given precautions taken. It is a tension structure, so that the building itself will give it structural support.
Rob, who has a history and family background in building construction, was quite skeptical of the structural integrity of the building. It proved to be excellent, and come together better than was thought.
Step 1: Materials
Materials aquired were 14? 4x8 OSB boards 100' of metal flashing (about 5-6" wide, and of substantial thickness) about 18 2x4s (for the roof, they dont need to be anything too fancy, we used salvaged wood that was fairly thin) Lots of screws (we used drywall, though we would encourage stainless steel) Paint Tar (dont need too much) Gravel (for the foundation) Vinyl steal material (this was an extra precaution)
Step 2:Painting and Tarring
The next step was to paint and tar the OSB boards. All of the OSB boards were painted on all edges, as OSB's weakness is moisture on the ends, which causes it to swell and rot. The paint applied on the edges, corners and such 3 inches in to the board should quell this. Additionally, Tar was applied to the bottom edge of 6 of the OSB boards, about 4 inches in, so that high water would be deterred from any prolonged exposure to the boards.
Step 3: Cutting
After the paint and tar dries, the next step is to start cutting the boards. Because we decided on 6' walls instead of 8', we were able to eliminate 3 OSB boards from the materials list and cut 3 in half for the topmost board.
-So, cut 3 OSB boards in half, making them 2'x8'.
-Cut 6 OSB boards in half diagonally, corner to corner for the pinweel roof (take extra precaution to ensure that these are straight and true, as they will ensure that the roof comes together well in the end. Also, if you are using foiled boards, cut them in half in opposite ways, so as to provide all foil on top)
-Cut 12 2x4s to have a long edge and a short edge, at a 30 degree angle, so that they can be linked together inside horizontally and form the hexagon with the walls
-Cut flashing strips into 6 8' strips and 6 6' strips for the walls, then additionally 6 more 8' strips for the roof
-Using a hammer punch, punch along roof strips and wall strips all along the edge, about 2-3cm in from the edge, making double punches near the ends. For the vertical wall strips, make sure that they are more dense. 2 people can set up a process doing this and have it done very quickly. Make sure to wear gloves as the flashing has sharp edges!!! (richard: i learned this the hard way. twice...)
For speed, have one small team cutting and punching flashing while another team draws and cuts board.
Step 4: Panel Construction
Wall Panels
With tar side down, attach 4'x8' OSB boards to 2'x4' boards, using the 2x4 with the long edge against the boards. Ensure that they are all flush, and that the 2x4 is evenly attached to both boards!
After this, attach flashing strip to one edge (left or right, doesnt matter, just keep it consistent throughout).
A trick Rob discovered with the flashing, to keep it flush as possible with the board, is to use the screw gun at an angle, pointing away towards the loose flashing end. It doesnt need to be an extreme angle, just enough to pull it taught when the head goes in.
Then, attach the flashing and the topmost 2x4 to the top of the 2'x4' OSB board. Leave a consistent space between the top of the 2x4 and the top of the OSB board (we left about 1/4 in). This makes placing the roof much easier and safer.
When attaching any of the flashing, ensure that you are placing less than half (more like a third) of the width of the flashing on the 1st board. This will ensure a good amount will be left to attach to the other board, whether roof or wall, given that the angle between will take up some of that width.