Earth Home

How to build a rammed earth home- part 2-by David Hagemann”

“In this section, it was somewhat difficult to decide which roof would be the easiest or which one would be the least expensive. Also, you might what to consider the most earth friendly. With the building having been designed for a flat roof (actually there is a slight pitch in the roof), we have the options of a metal roof, a composite roof, a rubber sheet roof, or an earth roof. As much as I love the sound of rain and small hail on a metal roof, this is the first roof I will eliminate. There needs to be a little extra insulation in the attic for metal (cold or hot), and the cost vs. a composite roof is a lot. A composite roof- rolled shingles, is the least expensive, but needs to be changed after a few years. A rubber sheet roof is still again a little more expensive than the metal roof, but if done properly, I think is the best. An earth roof- the covering of soil is the best insulation, and new to today’s way of building. So, after some pondering, I have chosen to describe how to build a combination of rubber sheeting and an earth roof. Also, this maybe the most expensive, so I will make notes as to what to exclude, if you chose to only do rubber type roofing.

First part of this is to install the all thread rods for the upper wall plates; 32 28”x 5/8” all thread rods.
a. On the front wall, you need to place the all thread rod 14” below the top of the wall and 171/2” below the top of the wall. These rods are also placed 4” from the inside of the side walls. Then place the rods every 4 feet.
1. Mark 3 ft. down from top rod and repeat procedure for ceiling plate and joist.
b. On the back wall, you need to place the rods 26” and 291/2” below the top of the wall and 4” from the inside of both side walls, then set rods every 4’.
1. Mark 2 ½ ft. down from top rod and repeat procedure for ceiling plate and joist.
Note: You could have left the back wall one foot lower than the front wall. This would have made run-off water no problem, but you would not been able to do the earth roof; then a metal roof might be the best option.
2. Now we need to install the rod support.
a. Find some metal plates, cut 4”x 4”- preferable ¼” thick. Drill a ¾” hole in everyone- centered. Place these plates on the outside wall, through the rod. Leave about 1” out from the plate.
b. Place a washer, lock washer, and nut on the rod. Don’t over tighten.
3. Now place the inside roof plates on front and back walls, use 2x6’s for both upper and lower joist plates.
a. After plate is on, put on a washer, lock washer, and a nut.
b. Level plate and tighten down nuts.
4. Second part is putting on the roof and ceiling joist.
a. Pick a side wall and mark off every two feet on plates for upper and lower joist.
b. mount joist brackets on the wall plate.
Note: If you don’t plan to do an earth roof you can place joist every 4 ft. instead.
c. Put up roof and ceiling joist.
d. Place vertical supports every 4 ft. between upper and lower joist.
5. Now put on 5/8” plywood sheets on roof joist.
Note: Make sure that all joints of plywood are flush and matching; and all nail heads are flush.
6. Apply adhesive to plywood. Don’t allow to dry!
7. Cut out slots or holes in back wall for drainage, about every 5 or 6 feet.
8. Put on roof flashing against walls and make sure that no water can get in between wall and roof.
9. Lay down rubber roof material and don’t let wrinkles to set in place.

You can now put on your soil for grasses or what ever you please. I would not exceed 8” of soil and I would not plant anything with deep roots.



I apologize to those who began to follow this building a year ago. While I was out looking for new property, I had a very strange thing happen to me; I ran into some very old friends…………The Weeders! You can find them at http://whoaretheweeders.blogspot .com”