Published • More About Monolithic Domes•
Decide to like the dome or not. If you don’t like the dome, don’t build it. A Monolithic Dome has many advantages, but none matter if an owner doesn’t want a dome.
Buying a Monolithic Dome and then attempting to mix and match it with conventional construction can be, and has been, disastrous. One of the first big churches we built was in Indiana. Its architect was embarrassed to use a dome. With the owner’s approval, the architect designed a Monolithic Dome hidden by a surrounding conventional building. In the years that followed, the dome performed flawlessly, but the conventional structure began suffering from the many problems conventional buildings often develop. Its flat roof leaked, so lawsuits were filed against the general contractor. And heating bills for the facility’s conventional sections were more than eight times those of the dome.
It’s impossible for a conventional building to provide the energy savings of a Monolithic Dome. A conventional building cannot be sealed like a dome can. Even if such a structure is sprayed with three inches of urethane, it will not have a Monolithic Dome’s huge thermal battery.
In Monolithic Dome construction, urethane foam blankets the exterior of the concrete. That turns the concrete into the dome’s thermal battery. The combination of the urethane on the exterior and the thermal battery of the concrete more than doubles the energy efficiency of a Monolithic Dome.
The dome’s roof is the major part of the thermal battery, so the underside of that roof must always be involved with the HVAC system. Any HVAC engineer who isolates the roof eliminates much of the available energy savings.
At times, architects hire HVAC engineers who do not understand or won’t listen to what we try to teach. Those engineers usually order three to four times too much equipment and often isolate the thermal battery. In such a situation, we can guarantee that energy savings will be severely compromised.
One such church, a large facility in Louisiana, has reported that its HVAC systems turns on and off very often; consequently, at least half of its savings are lost. For most months, the demand charges are more than the run charges. Nevertheless that church still has a much more efficient building than other churches near them.
Until recently, measuring a Monolithic Dome’s energy efficiency has been a problem. But now that measuring can be done with a computer program called HEED, developed by UCLA. The HEED program considers the thermal characteristics of the insulation and not just R Values.
This is clearly demonstrated by the use of thermographs. These show the energy efficiency of a structure. For further proof, you need only check with owners or administrators of Monolithic Domes, who will tell you the domes are doing precisely what we are talking about here.
Other Parameters for Decisions
Always remember that the underside of a Monolithic Dome’s roof works as a the major part of the dome’s thermal battery. If a building has a floor area of 2000 square feet, that battery will measure about 2000 square feet. Thus, we have one square foot of battery per square foot of floor area. If a second floor is installed, the battery is automatically cut in half: 1/2 square foot of battery for each square foot of floor area.
Nevertheless where land is expensive or not available, multiple stories may be necessary and/or desirable. The Monolithic technology will still be useful and generally preferred.
Other than losing some of the battery’s advantages, there is no harm done if the building is not used for mass occupancy. But if it is for mass occupancy, such as a church sanctuary, the loss may be larger or may necessitate more HVAC equipment. In general, we like to see single-story buildings. Then too, single stories have other advantages, such as no need for elevators or double stairs.
Consider multiple domes. A Monolithic Dome’s energy efficiency is high; consequently, it really does not matter if you use ten buildings or one building to provide 30,000 square feet. Often multiple buildings eliminate the need for many interior partitions, sound partitions, other expensive interior finishes and equipment. The need for expensive halls is often reduced or eliminated.
Multiple domes also make sense from a construction standpoint. If planned right, domes can be added as funds are procured and needs are encountered. This is a real plus, not often available with conventional designs. Generally, when more space in needed, conventional buildings are enlarged; consequently, so is the surface area exposed to weather.
Designing a Monolithic Dome with or without a stemwall may not be an easy decision. There are many issues: Using a stemwall is probably wise for a building with many doors and windows. But if the building is primarily for seating, a stemwall usually is not needed. Generally, a stemwall costs more than a design that brings the dome to the ground. This often provides a lot of nearly free space. So the stemwall decision should be made after considering all alternatives.
True – the dome with a stemwall will look more conventional, and in many situations it’s the best compromise. But never give up on alternatives. A fence or wall circumnavigating the dome can be designed to look like a stemwall, yet serve as an attractive, concealed storage area or drainage way.
Properly landscaped, a Monolithic Dome with or without a stemwall will look attractive and serve well. Today we have many design elements that stand alone and are not terribly expensive, but really enhance a structure. Demand some of them.