Openings in a Monolithic Dome can be made in several ways.
An augmentation is one such opening. It’s an extension of the Airform that creates a vertical surface, beyond the dome’s curve, where a door or window is installed.
Another type of opening is designed to fit inside the line of the dome. In other words, the opening is set back within the dome. This is an inset or cutout opening. The foam and concrete are stopped at the frames. With this type of opening, it is important to mark exactly where it will be placed. While placing rebar in the footing, omit rebar in the area of the opening.
Measuring The Opening
Measure from one side of the opening to the other (Figure 1). Divide the measurement in half to find the center point.
Using a level, make markings on the Airform from the center line to the desired height (Figure 2).
Measure from center point to edge of opening; then mark the measurement about every foot vertically until you reach your determined height (Figure 3).
At the point at which your vertical and horizontal lines meet, make a mark on the Airform (Figure 4). Then using a level, check your horizontal line.
Attaching the Bucks
Cut the wood into pieces short enough to fit the curve of the dome so no gaps are created. Any type of wood that is strong enough to hold the opening in place can be used (Figure 4). If wood will remain in the structure, use pressure treated wood to avoid rotting.
While one person inside the Airform pushes the piece of wood against the Airform (Figure 5) along the markings, another person on the exterior screws small stakes through the Airform into the wood (Figure 6).
This will hold the opening in place (Figure 7).
To complete the window bucks, add extra support to the curves by connecting interior bucks with small stakes (Figure 8).
Another way of making an inset opening is to make a frame to fit the opening. Using the measurements you have marked on the Airform, cut wood pieces to the size of the opening (Figure 9). Standing the frame up to the dome, check for level accuracy.
After the frame is in place, cut a piece of plywood to fit the curve of the dome (Figure 10).
To hold the opening in place, follow the same procedure of screwing stakes into the Airform from the exterior into interior window bucks.
To reinforce an opening, additional rebar is required along the perimeter of the window buck. If you have questions regarding the amount of extra rebar needed to reinforce an opening, call Monolithic for further details.
_*Note:* This article was first published in our Roundup_, Spring/Summer 1999.