Clearing the land

We chose a sloped, south facing property within a 1/4 mile of Interstate 91 to build our new office building. The southern exposure guarantees as much passive solar heating as a Vermont winter allows (although sometimes that's not very much) and the proximity to the freeway makes shipping and receiving a simple task.

First Forms

For a variety of reasons; efficiency, cost, exceptional strength, and architectural flexibility, we decided to build A 60' diameter geodesic dome from American Ingenuity, Inc. This 7,200 sq. ft facility started with an 18 faceted footing.

Prepping the Footing

This upper section of the footing was formed first, then later stair stepped down to a massive four foot frost wall.

Storing the Panels

In the midst of all this building, the dome panels arrived from Florida on two 53 ft. flatbed trucks. They were stored on site for two months while the foundation stage was completed.

Pouring the Footing

A concrete pumping unit made filling the footing forms an easy task.

Frost Wall Footing

Here in Vermont, footings are normally buried 4 ft. below grade. Because our shipping/receiving department operates out of the basement level and its double garage doors open to grade, a 4 ft. frost wall was needed to protect the foundation from frost heave.

Forming the Basement Walls

Once the footings were poured, the multi-faceted wall forms were put into place.

More Wall Forms

Due to the unconventional shape of our building and its sheer size, the local concrete contractor found himself scrambling to find enough "hinge type" wall forms. These forms were the only way to pour a solid 9 ft. high foundation wall consisting of 18 facets.

Pumping the Foundation Walls

The foundation walls were poured in two sections. Phase one was formed, braced, and poured, then the forms were stripped away and used for the second half of the foundation pour.

Carrier Beams

Once the full foundation was poured in place and waterproofed, the main carrier beams were installed.

Interior Footings

Although the dome shell itself is self-supporting, and, in fact, half the third floor is actually hanging from the shell via suspension rods embedded within the seams between the panels, the three story central stairway and the floors themselves are supported by steel posts poured into a dozen interior footings.

Installed Subfloor

Finally, after three months of construction, we have a platform upon which to start the dome shell phase.

First Dome Panel

Although the bulk of the geodesic dome consists of interlocking triangle panels, 15 rectangular "riser" panels make up the first layer. Because the dome curves inward as the layers of triangles are installed, the riser panels raise the entire structure 4 ft. before this effect comes into play. The result is more usable space on the first floor.

Placing the riser panels

Except where an entryway is required (and in that event both risers and triangles are left out and replaced with "dormer" panels), the riser panels ring the entire structure.

Building the Rib System

Once the riser panels are concreted in place and allowed to cure overnight, a 2" by 4" geodesic rib system is constructed using hubs supplied by the dome manufacturer. These ribs aid in correct panel placement and also help support the panels until each layer is concreted securely.

Rib System (cont.)

Building the rib system for a dome this size took a full three days. Meanwhile, those workers not involved in the rib process concreted the vertical seams of the riser panels. #5 rebar sticking up from each corner of the foundation was embedded into these vertical seams to anchor the dome to the foundation.

More Ribs

Slowly the ribs take on the rounded shape of the final dome.

Long View

From a completely wooded lot three months earlier, the dome begins to emerge.

Geodesic Skeleton

The completed rib system. Since this is a temporary structure, every board making up this skeleton later becomes part of the interior walls.

Rib System

The completed rib system acts as a guide for correct panel placement as well as a temporary support for the concrete and foam panels. Additional bracing supports the riser panels until the first row of triangles are connected to them.

First Layer

The dome panels are made of 9" thick EPS foam bonded to a 3/4" layer of wire mesh re-enforced concrete. The mesh extends about 6" beyond the edges of the panel, and once the panels are positioned onto the rib system, c-rings connect the overlapping wire mesh.

Seams

When a layer of panels has been placed around the circumference of the dome, and the wire between them c-clipped, the seams are filled with a special mixture of fiber re-enforced concrete. After a day of curing, the panels are self supporting and the next layer of triangles can be installed.

Second Layer

In this photo, the first few panels of the second layer have been positioned and concreted into place. The remaining panels (foreground) will be craned onto the rib system during the next several days. As many as 19 panels were positioned in a single day.

Setting the Triangle Panels

With the rib system nearly enveloped in panels, the final few triangles are craned into place.

Each seam requires two layers of concrete. Because the first layer is structural, every seam is concreted to the top of the wire mesh that interlocks each panel. Later, a second finish coat is applied over the first layer, and simultaneously to the edges of the panel itself. This second coating of concrete is damp sponged during the early curing stage to give the seam a texture similar to the factory panel.

Panel Placement

The final panel of the main shell is hoisted into place. Any area without a panel indicates a window. Later, special dormer panels are connected to the body of the shell and concreted into place.

Building the Cupola

As mentioned before, the panels in the dome kit are a special mix of wire re-enforced concrete bonded to 9" of Expanded Polystyrene foam. In effect, while placing the panels, the builder is simultaneously insulating the structure. Nine inches of EPS foam has a R-value of 36, so, when finished, the building fits into the "super insulated" category.

In the above photo, the columns of the cupola have just been poured. The window frames spanning the space between columns are cast into the columns at the same time.

Completed shell

The final five triangle panels are used to roof the cupola. Special extensions are then wired and concreted to the five triangles to create eaves around the cupola.

Finished Building

When the final dormer panels were installed around the windows, the structure was prepped for painting. The addition of glazing, doors, and a wraparound deck completed the exterior of the building.