Our House Construction Exterior Shell
Page 5

All the inside stuff.
(or what happens after the excitement of inflation and lighting up the shells at night)
Step 1. Foam & Block-outs
Once the airform has been inflated and the air lock is attached, the polyurethane foam is sprayed inside the dome. Successive layers are sprayed until the proper thickness is reached. This foam preforms the insulating function of the dome as well as the initial structural strength of the dome.
Horizontal lines are drawn around the dome to help us install our horizontal rebar in straight lines. If you look closely you can see the stickers stuck into the foam on the lines.
Anything electrical need to be planned for and the conduit installed before the rebar is placed on the walls. You see the lines for the ceiling fans have been routed into the foam and after the rebar is installed the boxes will be attached to the rebar.
All openings must be planned for in advance.
Its awful tough to hammer through shotcrete at 6.000psi - its tough!

We made a pattern out of foam board for our curved openings and traced them on the wall after determining where they should be on each dome.
Note electrical in the wall.
Once the openings are marked they need to be blocked off so the shotcrete will not be shot there. We tried a number of methods and the one that was the fastest, easiest and worked extremely well is illustrated here.
Here our dome builder Mert Hull is using a jig sow to cut a slot into the foam following the previously outlined shape.
We used a hack saw blade cut off so that
only extended about 1" into the foam.
These pictures show how easily we where able to shape the curved openings. By using short length of tin we where able to form a nice neat curve. Note that we made the top and bottom of the openings horizontal by changing the angle of the jig saw base plate.
This procedure worked for rectangular window
openings too. We did duct tape the corners together.
We also plan three sun tunnels that must go through the dome
so sona tubes where used to form the opening block out.
Can't forget the plumbing! After meeting with the plumber we installed various sizes of pipes (some tin and some pvc) to provide the appropriate openings.
Step 2 Pre-Shell & Rebar (lots of it!)
Once all the openings are planned for and blocked out, the entire inside is sprayed with a thin coat of shotcrete. Its about 1/2" thick and include fiber for reinforcement.
This pre-shell makes the shell very rigid and also locks the stickers into the shell. The horizontal rebar is applied to the shell first by using the twisters to hold them in place around the domes.
Starting at the bottom and carrying it all the way to the top of each dome.
Too bad you have to cover all the rebar up! It makes some interesting patterns as it goes up the walls.
These unions also required additional vertical rebar
following the curve from footing to footing.
Having multiple domes as one building we have to
tie each dome together where they meet thus
making them one building as well as stronger.
Extra reinforcement is place around any openings just like
convectional construction where you install double studs and
headers. Here we use a larger sized rebar that extends 2'
beyond the opening on each side.
We built a very sturdy column between tow large openings.
Can't forget the suspended fireplace in the patio! Mert is prepping
another sona tube so we will have an opening for the smoke stack.

Click on any picture to see it larger
This is a little tough to see but starting in the kitchen dome looking to the right you can see the main dome (front room and dinning room) and beyond that the private (bedroom) dome.
Looking to the left you see the patio (scaffold inside) and the arched opening into the two garages and shop..