Answers To Our Most Frequently Asked

Energy Efficiency Questions

Q: Where can I view on your web site, the energy bills for your Florida Dome Offices and for a Florida Dome Home?

A: To view the FP&L utility bills showing the Ai 3,700 sq.ft. dome offices can be cooled for less than $55 a month during Florida's hottest months, click on Office Energy Bills. To view the FP&L utility bills showing a Florida 1,200 sq.ft. 34ft in diameter dome can be cooled for less than $22 a month during Florida's hottest months, click on Home Energy Bills.  Heating Ai domes is even easier than cooling because when heating, the heat generated by computers, refrigerators, dishwashers, clothes dryers is used and does not need to be overcome during cooling.

Q: Tell me about an American Ingenuity dome beating a home sponsored by the utility company, Florida Power & Light, to wind  the award for Most Energy Efficient Residential Unit in the southeastern United States.

A: Florida Power & Light is a nuclear powered utility company in Florida. FP&L sponsored the design of a passive solar home and entered it in a contest held by the Southeast Builder's Conference, a division of the National Home Builders Association.  An American Ingenuity dome was entered into the same contest.  The Ai dome beat the FP&L home to win the award for the Most Energy Efficient Residence in the southeastern United States. The Home also won the Grand Award for all energy efficient categories...beating out the FP&L home in a second category.

A: A 5+ Energy Star rating, the highest rating given, Energy Star is a joint program between the Environmental Protection Agency and the United States Department of Energy that is designed to promote products, buildings and homes that use less energy without sacrificing quality.

American Ingenuity has received in the past the Energy Star endorsement for our dome homes, making us the first among Geodesic Domes. Our domes not only qualified but we far exceeded their efficiency standards that are derived from the Model Energy Code.

In an American Ingenuity dome, you can receive a 5+ Star rating, the highest rating given. When financing, this rating will entitle you to the maximum benefits like reduced fees and lower interest rates. The Energy Star Rating cannot be given on a building kit...only on a finished dome. Therefore, once you build your dome you can apply for the Energy Star Rating. Energy Star's web site is http://www.energystar.gov

Q: What do I need to consider when searching for an ENERGY EFFICIENT house?
A: To best answer that question let us examine how most of the heating and air conditioning is lost in a house. The major loss is usually through the walls and ceiling with the amount of loss directly proportional to the combined area. Solution, minimize the surface area of the house. Domes have about 20% to 40% less surface area than an equal size conventional house. This results in an equal and significant improvement in the efficiency.

The insulation value of the walls and ceilings are important but you cannot just compare R-values. R-values provided for conventional houses represent optimum conditions. They do not take into consideration that the insulation is interrupted by the framing, has voids, settles and absorbs moisture. In our domes, the E.P.S. insulation is continuous, rigid and it will not settle or absorb moisture. R-28 E.P.S. insulation in our dome exceeds the performance of R-45 fiberglass in a conventional house.

Blower tests repeatedly show that wood frame houses loose 10-25% of their heating and AC through the numerous leaks in the walls, attic, electrical outlets, etc. It is very difficult to seal these leaks due to their volume and inaccessibility. American Ingenuity domes are sealed airtight on the outside of the insulation; therefore, eliminating the energy absorbing leaks.

The insulation on Heating and AC ducts is usually only R-6 to R-8. In addition, when the fan is running, the air in the ducts is under pressure and thus the ducts are more inclined to leak. Ducts in the attic, or anywhere outside the insulation envelope, account for sizable energy loss. In American Ingenuity domes all of the ducts are inside the insulation; therefore, there is zero loss in the ducts even if they leak and are not insulated at all.

If you add up the potential energy savings of American Ingenuity dome living, you will understand why our dome owners often claim savings in excess of 50%.

To learn more about heating and cooling an American Ingenuity Dome click on HVAC.

Q: How does your insulation R-value compare to other wall R-values?
A: The following are comprehensive wall values based on the average value of the complete wall. For example the comprehensive R-value:

Q: Does thermal mass affect energy efficiency?
A: No. Generally speaking, in a home, thermal mass is the amount of stuff inside the house that retains heat. Although thermal mass accounts for the fact that some things have a greater "thermal capacity" to store heat than others, to understand its effect you can think of it as the total weight of everything contained in the house.

With more thermal mass (heavy stuff) inside your house more heat will have to be added or removed to change the temperature. Expressed another way, if heat is not being added the temperature will be slower to change.

Does Thermal Mass effect the energy efficiency of the house? No.

As heat in the house is lost through walls, windows, etc. the temperature drops. The thermal mass releases (loans) heat into the house slowing down the temperature change. When the heating system turns on, it must replace heat lost to the outside and it must  replace (pay back) that heat given off by the thermal mass. There is no long-term gain or loss, all of the heat given off by the thermal mass must be replaced. The amount of heat required to maintain the temperature inside a house is solely dependent on the amount of heat that escapes to the outside.

All houses have walls, floors and usually fixtures, appliances and stuff that will retain heat. A large amount of thermal mass can cause long on/off cycles of the heating system when shorter cycles would stir the air more frequently providing more comfort and uniform temperatures inside. The recent generation of thermostats are a proven money saver by lowering the inside temperature (which lowers the heat loss to the outside) during those hours you are away at work, etc. A large thermal mass makes it much harder to change the temperature; therefore, reducing the savings.

During the summer while using AC (substitute cold for heat) the effect remains the same.

Q: Can I use alternative power sources with my American Ingenuity dome?
A: Yes. By providing your own Alternative Power, you can live in a remote location (less expensive land) and still have all the amenities of a developed area. The alternative power systems typically consist of a power source, storage device and conversion systems. Most systems use photovoltaic cells but is some cases gasoline or diesel engine generators or wind or water driven generators are practical. The storage device is usually large batteries. The conversion system allows you to have 110 volts AC and use conventional appliances. The technology is very refined and the systems are top notch.

The cost of the system will depend directly on the amount of power that you will need. By first investing in an energy efficient house, you will reduce your power demand and save money. If you are considering an American Ingenuity dome home, you couldn't make a better choice and you will be doing your part to conserve power and lower greenhouse emissions.

If you are also connected to the local power grid, you will not need batteries for backup and in most cases you get paid for putting power back into the system.

If the cost of the system is included in the home financing it can be paid off with a little higher monthly mortgage payment. Not having an electric bill may even it out.

Utilizing an alternate power source does have a few drawbacks: COST: while systems are getting more affordable, they are still expensive. It is still less expensive to buy power from mass-produced power companies unless you are far from the power lines. MAINTENANCE and RELIABILITY: Most systems are very reliable but occasionally they need attention. Several of our dome owners have alternative power systems and are very satisfied with the results.

If you are considering an alternative power system in your dome the magazine Home Power offers many solutions. They can be reached at their web site http://www.homepower.com 

SOLAR HOT WATER PANELS:

Q: Would you give me more information about solar hot water heaters and photovoltaic panels?
A: An article in Mother Earth News reported that since 1970, the demand for electricity has outpaced the World's population growth by more than 20 percent. They continue and explain how we are ignoring the warning signs, that Builders are still constructing poorly efficient housing and others are overlooking the importance of renewable/alternate energy sources.

The first and most important step is to limit or reduce the energy loss in the home. An investment in good, uninterrupted, insulation and a design that does not leak the conditioned air to the outside has the best return. The savings is not only in the reduced energy loss but, also in the reduced cost of a smaller heating and air conditioning system. The next step is to replace some of the energy, which is consumed. A solar water heater has proved to have quick payback in most parts of the country. In fact, sometimes they can be financed and save more money in reduced electric bills than the cost of payments. When they are paid off it becomes pure savings. Photovoltaic cells have continued to improve in efficiency and cost.

The Mathes' dome (34' dome home with 30' garage dome) in Florida utilizes a solar water heater and photovoltaic panels to power their lights and refrigerator. Although, their A/C, washer, well pump and TV are still connected to the meter, their total electric bill was less than $150.00 for the year. The dome owner says our proposed heating and A/C savings are "way, way off." The owner/builder also states, "This has been a wonderful experience that I would not trade for ANYTHING!" Click on Photovoltaic to learn more.

Q: How did the American Ingenuity dome perform in the energy efficiency tests at the Florida Solar Energy Center?
A: Superbly. Test findings were released after a yearlong study prepared for the U.S. Department of Energy by the Florida Solar Energy Center, a governmental consumer agency, in cooperation with the University of Oregon and the University of Central Florida. This study compared an American Ingenuity dome with an energy efficient, conventionally built structure and a super-efficient Styrofoam house designed by Dow Chemical. It came as no surprise to us that our test dome far surpassed both the conventional and Dow test houses in being THE MOST ENERGY EFFICIENT.

Although the test was conducted in a temperate locale without summer and winter temperature extremes, the American Ingenuity dome outperformed the other structures. In the summer, the energy savings for the dome exceeded 36% and during the winter, the energy savings exceeded 42%. In areas of severe cold and heat, savings would be expected to be considerably higher.

Also, the blower door test showed the dome to be 56% tighter than the conventional test structure and 29% tighter than the Dow house. In tests using infrared, thermal irregularities in the dome were shown to be insignificant.

You can call the Florida Solar Energy Center at 321-638-1000 or write them at 1679 Clearlake Rd, Cocoa, FL 32922.

Q: Which heating and air-conditioning system is the most practical and efficient for my location?
A: Keep in mind that because of the superb energy efficiency of the dome the required size of your air conditioning and heating system is reduced to half that of a typical home. It is usually not economical to purchase super-efficient systems because the energy savings is also reduced. The smaller sized domes can be cooled with a window air conditioner. The best heating system will vary with the area and the type of fuel that is readily available. A ventilated wood stove may provide all the needed heat for even our larger domes located to cold climates. A ground water (or water-to-air) heat pump is very efficient for both heat and cool. It uses the constant, moderate temperature of the underground earth to absorb or provide the heat instead of outside air. Besides, being more efficient than an air-to-air unit, it can efficiently produce heat when the outside temperature is below freezing.

Q: Can a radiant in floor heating system be installed in my dome?
A: Yes. Check your yellow pages or Google local Radiant Floor Heating Subcontractors.

Click on Radiant Floor Heating to learn more.

Q: Why are your dome homes so energy efficient?
A: You can save 50-70% on heating and air-conditioning costs with your American Ingenuity dome over a conventionally built home. Some of the reasons for this superb energy efficiency are:

• Super insulation that does not degrade with time, moisture, or compaction.
• Spherical shape means reduced exposed surface.
• Airtight exterior virtually eliminates energy leakage.
• Solid thermal envelope.
• Uniform R-value, the insulation is not interrupted with structural members (e.g. 2X4's roof trusses). The only breaks are for doors and windows.
• Downsized heating and cooling equipment.

Your kit comes with lifetime R-28 E.P.S. insulation (22' with R-14), or if you choose, thicker R-36 E.P.S. insulation is available. Even in cold climates, you may find that a single ventilating wood stove will provide all the heat your home will need. 

The Expanded Bead Polystyrene (E.P.S.) Insulation that American Ingenuity utilizes is seven inches of sturdy, rigid R-28 modified E.P.S. insulation, which forms the core of each component panel. The E.P.S is one pound per cubic foot density (pcf).

The E.P.S. insulation will not rot, shrink, absorb moisture, compact, or deteriorate due to age or weather. It also acts as a vapor barrier for your home, providing stable performance year after year.  The E.P.S. is:

·         permanent

·         chemically and thermally stable

·         resistant to mildew

·         provides no nutritive value to animals, plants, microorganisms

·         non-irritating to skin

·         Chlorofluorocarbon (CFC) and formaldehyde free.

What kind of vapor barrier will American Ingenuity dome have?  Approximately one quarter of the energy consumed by an air conditioner is used to extract water vapor from inside the house. Water vapor easily passes through most building materials and is readily swept into homes through joints, seams and through the attic. The E.P.S. insulation that A.I. uses provides a good vapor barrier.   And the A.I. building system provides for an air tight house.

During the US Dept of Energy Study on energy efficiency in housing designs, the blower door test showed the American Ingenuity dome to be 56% tighter than the conventional test structure and 29% tighter than the Dow house.  To see if air was passing through walls of the dome, tests using infrared were performed. Thermal irregularities in the dome were shown to be insignificant.

Per the manufacturer of the E.P.S. that American Ingenuity uses, "the E.P.S. is closed cell and will not absorb more than 2.5% of water based on volume".  E.P.S. is often used as flotation for docks because it will not absorb water. 

Per E.P.S. manufacturer's data sheets, the following description was given to explain how the E.P.S. is affected by Moisture:  "To retain their original insulation value, all insulation materials must remain dry.  Water is a good conductor of heat so high moisture content in the insulation results in a significant loss of performance.  This is particularly so with fibrous materials which must be positively protected by an efficient vapor barrier.  There are two ways in which moisture can affect insulation materials: Water absorption from contact with damp surfaces (or rain penetration) or from interstitial condensation of water vapor.  E.P.S. is a closed cell material and has minimal water absorption and low water vapor transmission.  Both of these properties are to a large extent, density related, but also to the degree of fusion of the material.  Tables 4 and 5 show typical performance figures for good quality E.P.S. boards manufactured to Arco Polymers recommendations.”           

Table 4  Water Absorption

Density (pcf)                                  1.0 lb                            1.5 lb                             2.0 lb
(pounds per cubic foot)

Water absorption (% vol)        less than 2.5                  less than 2.0                  less than 2.0

Table 5 Water Vapor Transmission (WVT)

Density (pcf)                                                     Grains (hr/sqft) In/Hg (Perm inch)

1.0                                                                                            1.2-2.2

2.0                                                                                            0.6-0.8

2.5                                                                                            0.5-0.7

3.0                                                                                            0.5-0.7

The amount that a material will breathe is measured in perms or sometimes perm inches.

 “Note: FHA requirements for perimeter insulation are that the original K value of the material must not increase by more than 15% after repeated wetting and drying cycles.  Tests have been carried out on nominal 1.0 pcf density E.P.S. with an original K value (at 75 degrees F) of 0.26.  After submersion the K value was found to be 0.28--an increase of only 7.7%.”

 “Climatic Changes:  E.P.S. board has been used as an insulation material in various types of building structures for over 35 years in climatic conditions ranging from Arctic cold to desert heat and has performed satisfactorily.  E.P.S. does not become brittle at sub-zero temperatures (in fact its K value improves) and suffers no loss of impact resistance at -100 degrees F compared with 73 degrees F.  The maximum recommended continuous operating temperature is 175 degrees F.  Roof surface temperatures in Southern States may reach this temperature for short periods, but with suitably designed roof systems E.P.S. can be used under these conditions.”

In A.I.'s building system the water is stopped on the outside surface because the concrete is rich and dense enough to inhibit significant absorption and it is coated with a primer and two coats of good quality exterior concrete paint which further insures against leaks.  If a leak occurs, the remedy is another coat of paint in that area. If and when any water gets past the concrete very little will be absorbed by the E.P.S.

 Now this brings up breathability of the E.P.S.  The amount that a material will breathe is measured in perms or sometimes perm inches.  E.P.S. will breathe enough to allow it to dry out inside our walls.  At the same time it is tight enough to also serve as a good vapor barrier. Ai’s insulating concrete panel (ICF) is made from expanded polystyrene (E.P.S.) molded into lightweight foam blocks. The foam itself provides excellent insulation with an R value of R-24. The R-value of E.P.S. remains constant. (R-values of traditional fiberglass insulation decreases when the material is wet or damaged.)  Ai chose to manufacture its dome component panels with Modified Expanded Polystyrene (E.P.S.) foam because of its fire performance, structural performance, and environmental advantages.  Modified E.P.S. contains no formaldehydes or toxic chemicals, and uses fewer resources to manufacture than other insulation products.  E.P.S. provides you with superior thermal performance to better insulate your buildings, and no harmful CFC’s have ever been used to manufacture it.

You can now recycle your jobsite scrap through a network of manufacturers, re-processors, and retailers across the country. E.P.S. is a valuable resource than can be remanufactured into foam packaging or made into an amazing array of polystyrene products. 

To locate your nearest E.P.S. collection site, call the RECYCLING HOTLINE at 1-800-944-8448.  Please recycle jobsite scrap.

Expanded Polystyrene (E.P.S.) Facts

E.P.S. is manufactured from expandable polystyrene beads containing a hydrocarbon blowing agent and a flame-retardant additive. It is a closed cell, lightweight, resilient, foamed plastic composed of hydrogen and carbon atoms. There are two common types of polystyrene foam, Extruded Polystyrene or XE.P.S. (Popularly known by its Dow trademark, Styrofoam) and Expanded Polystyrene (E.P.S.). Both expanded polystyrene and extruded polystyrene are used extensively as thermal insulation in industrial, commercial and residential construction.

During the processing of E.P.S., steam heat softens the beads and causes the blowing agent to expand to produce moisture-resistant multi-cellular particles which increase in size up to 40 times their original volume.

Following a period of stabilization, during which time the beads lose their moisture, the blowing agent condenses out and air diffuses into their cellular structure, the pre-expanded beads are molded into blocks of insulation.

The benefits of E.P.S. thermal insulation products are its lightweight, has stable long term thermal resistance, no R-value loss over time (Source: 1985 Study conducted by Structural Research, Inc. for NRCA, MRCA, and SPI), and cost effectiveness when compared to other rigid board insulations on the basis of R-value.

Is E.P.S. a water, vapor or air barrier?

E.P.S. is considered water resistant and vapor permeable and at the density and thickness that American Ingenuity utilizes, the material acts as both a vapor retarder and an air barrier. This characteristic essentially moves the dew point to the exterior side of the concrete wall, minimizing interior humidity in the summer, and at the same time eliminates air infiltration in all seasons which is recognized as a major cause of R-value loss in fiberglass insulation. Air exchangers or heat recovery ventilation systems are highly recommended.

Is E.P.S. foam toxic?

E.P.S. is an inert, non-biodegradable organic plastic foam which will not rot and is highly resistant to mildew. According to National Bureau of Standards Combustion Tests, data collected from seven labs concluded that under the worst-case fire scenario, fumes from E.P.S. are no more toxic than those from wood (Douglas Fir).

Is E.P.S. Flammable?