effectiveness | AiDomes

To read about energy efficiency and the American Ingenuity Dome, view Efficient Ai Dome.

The following information came from:

The United States Environmental Protection Agency’s Energy Star Program’s web site is Energy Star.

Air will leak through a building envelope that is not well sealed. This leakage of air decreases the comfort of a residence by allowing moisture, cold drafts and unwanted noise to enter and may lower indoor air quality by allowing in dust and airborne pollutants. In addition, air leakage accounts for between 25 percent and 40 percent of the energy used for heating and cooling a typical residence.

The amount of air leakage in a house depends on two factors. The first is the number and size of air leakage paths through the building envelope. As shown in Figure 1, these paths include joints between building materials, gaps around doors and windows, and penetrations for piping, wiring, and ducts. The second factor is the difference in air pressure between the inside and outside.

Pressure differences are caused by wind, indoor and outdoor temperature differences (stack effect), chimney and flue exhaust fans, equipment with exhaust fans (dryers, central vacuums) and ventilation fans (bath, kitchen. To prevent air leakage, it is important to seal the building envelope during construction prior to installation of the drywall. Once covered, many air leakage paths cannot be accessed and properly sealed. There are many products available for air sealing including caulks, foams, weather stripping, gaskets and door sweeps.

Air sealing the building envelope is one of the most critical features of an energy efficient home. Look for the results of a “blower door” test (typically included with a Home Energy Rating) to ensure that your Energy Star labeled home had all air leakage paths identified and sealed using appropriate materials.

Once a house is tightly sealed, you will want to make sure there is adequate fresh air for ventilation. It is better to use controlled or active ventilation than to rely on air leakage. In many Energy Star labeled homes, an active ventilation system is installed along with air sealing to ensure that fresh air is provided.

Benefits: air sealing the building envelope can provide many benefits including:

  1. Improved Comfort: A tighter building envelope reduces the amount of unconditioned air, drafts, noise, and moisture that enter your home. Proper air sealing will also minimize temperature differences between rooms. As a result, tight envelopes can maintain a more consistent level of comfort throughout a house.
  2. Improved indoor air quality: A tighter building envelope reduces the infiltration of outdoor air pollutants, dust and radon as well as eliminating paths for insect infestation. Properly sealing the building envelope will also reduce moisture infiltration from outdoor air in humid climates.
  3. Increased quality: Building codes establish the legal minimum construction standards. Energy Star labeled homes, constructed to exceed these codes with air sealing, can offer a better quality product.
  4. Lower Utility Bills: Air leakage accounts for 25 percent to 40 percent of the energy used for heating and cooling and also reduces the effectiveness of other energy-efficiency measures such as increased insulation and high-performance windows. Thus. Air sealing results in lower utility bills.
  5. Fewer condensation problems: Condensation can lead to mold and mildew problems. In hot, humid climates, moisture can enter into wall cavities through exterior cracks and result in costly damage to framing and insulation. In cold climates, gaps in the interior walls allow moisture from warm indoor air to enter wall cavities and attics. This moisture can condense on cold surfaces and lead to structural damage. By significantly reducing air leakage, Energy Star labeled homes can reduce or eliminate these problems.
  6. Reduced obsolescence: Based on recent trends for improved efficiency and higher indoor air quality, tighter building envelopes are expected to become standard practice for the building industry. Since it is both difficult and costly to make the building envelope tighter after a house is constructed, it is best to seal all joints, holes and seams during construction. Energy Star labeled homes constructed to exceed current building codes are therefore, expected to be less vulnerable to obsolescence.
  7. Improved resale position: Air sealing a home can provide the many impressive benefits discussed above and lead to a more comfortable, quieter and better quality home with lower utility bills, fewer condensation problems and reduced obsolescence. These benefits can translate into higher resale value.

Resources used:

    1. The Consumer Guide to Home Energy Savings (Wilson and Morrill), 5th edition, 1996, available from the American Council for an Energy Efficient Economy at 510-549-9914
    2. Homemade Money (Heede and the staff of RMI), 1995, available from the Rocky Mountain Institute at 970-927-3851
    3. Caulking and Weatherstripping fact sheet available from the Energy Efficiency and Renewable Energy Clearinghouse (EREC), POBox 3048, Merrifield, VA 22116, (1-800-363-3732)

This article covers Ai’s 48′ Dome Panel’s Load Test.

load test

48′ Dome Panel Load Test

load of almost four tons of sand & bags of Portland Cement on panel

The above photo shows the additional 40 bags of Portland cement that were set on top the sand loaded panel, bringing the total weight on the panel to almost four tons. The center deflection increased to less than 3/8 inch. The grand total deflection of less than 3/8 inch with almost four tons of weight was astonishing to us. Our panel withstood 170 lbs. per sq. ft. of load.

Q: Do you have an engineering statement about your dome panels that can be submitted to my building department?

A:  Yes, to view the statement click on Engineering.

In October 2000 Ai performed a load test on one of its 48′ triangular shaped prefab building kit panels. The test was performed on Ai’s largest panel using the standard 7″ thick E.P.S. insulation, ¾” thick concrete exterior reinforced with galvanized steel mesh and a fiber reinforced plaster on the interior. The strength of the component panel can best be determined by measuring the deflection of the panel as a load (weight) is applied in increments. The panel was placed horizontal. Its weight and the weight of everything placed on it was only supported along the outer edge of the panel. The loading of the panel was done by adding sand in 470 lb. increments. Plywood sides were attached to the panel edges so sand could be spread evenly, providing a uniform load.

The deflection was measured in the center and six other locations. At all measured points a steel ruler was attached to the panel extending high enough to be visible when the panel was fully loaded with sand. A surveyor’s transit allowed the engineer to measure the deflection.

After 3,783 lbs. of sand was dumped on the panel its center had deflected less than 1/16 inch. Three days later, the deflections had only increased to 3/32 inch. Our own amazement at the strength made us even braver; so we cut through the interior plaster on the bottom of the panel. Even then the deflection was less than 3/16 inch.

Ai had not expected this exceptional strength. We could not mound the sand any higher so we set a pallet of 40 cement bags on top of the sand thinking, “This could do the panel in.” That doubled the weight and the center deflection increased to less than 3/16 inch.

The grand total deflection of less than 3/8 inch with almost four tons of weight was astonishing to us.

A 120-mph wind will exert a pressure of 30 lbs. per sq. ft. on a vertical wall and a snow load exceeding 90 lbs. per sq. ft. is rare. Typically snow loads are 20 to 50lbs. per sq.ft.  American Ingenuity’s triangular shaped 48′ component panel withstood 170 lbs. per sq. ft.

load test 2

This picture was taken after Ai had loaded 3,783 lbs. of sand onto our 48′ dome panel. After the sand was dumped on the panel its center had deflected less than 1/16 inch. Three days later, the deflections had only increased to 3/32 inch. Our own amazement at the strength made us even braver; so we cut through the interior plaster on the bottom of the panel. Even then the deflection was less than 3/16 inch.

The men in the photo from left to right are:

  • Michael Busick, inventor of American Ingenuity’s building panel and building method
  • Luke Miorelli, mechanical engineer
  • An engineer who was an independent observer
  • Leo Cherbano, American Ingenuity’s plant manager

 I would like to completely bury the dome. Is this possible? 

  • Ai does not recommend this; however iIf you want your Ai dome completely covered with soil, let us know the depth and Ai will quote a fee to hire local engineer to calculate load of the soil, determine rebar spacing that will be installed on top of the finished dome, depth of concrete to be gunited on to the dome and what posts will be needed to support the weight of the soil and concrete on the dome.
  • A dome like an arch, increases its effectiveness as it is compressed so it will support partial earth berming or any snow load. We have fortified our reinforced concrete with space-age fibers and special admixtures, as well as galvanized steel. As the panels of the dome are assembled, the beveled seams between them are concreted, creating a network of interlocking arches of structural beams.
  • Our dome lends itself very well to earth berming because of the strength of the dome shape and the totally concrete exterior wall, with no materials to rot. Ai’s domes have been bermed with as much as 4 feet of backfill. However, if you earth berm your dome, install a drain system to draw water away from the foundation. Plans for this french drain system are included with our basement plans.
  • The Ai Dome could be bermed higher or even buried, but we do not recommend it because the additional expense of labor and extra concrete would probably not be worth the gain. A dome or a structure that is not buried would never have to withstand loads greater than 100 lbs. per sq.ft. If a structure is buried the earth could put loads in excess of 500 lbs. per sq.ft.  Ai does not design our standard dome for those extreme conditions that would normally never occur.  However the dome can designed to withstand these loads.
  • Four feet is the maximum height of back fill that can go back against the dome as currently designed. Back fill higher than this would cause more expense and complications than is likely to be worth while. Consider landscaping with plants to enhance the appearance that you want.

Windows can add a lot to a home’s character. But if they’re old and worn, they can also add to your heating and cooling bills.

From Better Homes and Gardens.

In older houses, faulty windows can account for a third of the total heat loss in winter and as much as 75 percent of interior heat gain in summer. Look for the following telltale signs that a window has lost its effectiveness:

  • Stand inside your house on a windy day with a lit candle near the window’s operative edge. If the flame flickers or goes out, your weather stripping might be damaged.
  • During the winter, if a window develops ice buildup or a frosty glaze on the interior of the pane, the ventilation in your home may not be adequate. Another possibility is that your window may not be providing enough insulation value, a situation that can make your heating bills soar.
  • If you need to prop open your window with a book or a stick, the window may have lost its functionality.
  • Sit near your window. If you feel cold air coming in during the winter or warm air during the summer, your windows have little insulation value. This means you’re paying more to heat and cool your house to compensate for the exterior air entering your home.
  • Do your windows get fogged with condensation? If so, you may have a seal failure and need to replace the glazing or the entire window.

In some cases, replacing broken panes and tending to loose or missing weather stripping may buy some time. If your windows are old and ill-fitting, however, you need more than stopgaps.

Replacement window options:

Wood is the choice of most homeowners. Wood is strong, insulates well, and has natural appeal and a warm look. It needs exterior maintenance, and interior surfaces can be painted, stained, or finished any number of ways.

Vinyl windows do not need to be painted or stainedóa plus on the exterior. They offer good insulation value and strength, making them a viable alternative to wood.

Aluminum windows have a stronger frame but poorer insulation than wood or vinyl. They’re fine in areas with a mild climate, and are also used for commercial applications.

Fiberglass combines the higher strength and stability of aluminum with the insulating properties of wood and vinyl. Fewer options are available at this time, as fiberglass is just beginning to show up in the window market.

Combination windows are available with wood on the interior and vinyl or aluminum on the exterior, combining the look of wood with a low-maintenance exterior material. This is known as “cladding” (as in vinyl-clad or aluminum-clad).

Features to consider:

Energy efficiency. Almost any good-quality window available today incorporates two pieces of glass with a sealed airspace between then as a buffer between indoors and out. Some windows are even triple-paned. You may have the option of argon gas instead of air between the glass to further the window’s insulating abilities. Most window manufacturers also offer such options as low-E glass, which reflects heat and screens out the sun’s rays.

Design. Windows are available in shapes ranging from quarter rounds to ovals. Consider an arrangement of smaller windows instead of one large one, or vice versa.

Ease of installation. The easiest type of replacement window is a frame-within-a-frame design that can be installed in an existing frame without disturbing walls or trim work. Some are sold in kit form, complete with hardware, for standard sizes. If your original windows have divided lights or panes, look for multipane replacements or snap-in grilles that match glass dividers on the old units as closely as possible. If your windowsills are rotting or damaged, however, you’ll need to replace the old frame as well.

Ease of maintenance. Weather-resistant materials will reduce your regular maintenance; vinyl or aluminum-clad exteriors need no painting. For ease of cleaning, choose windows that tilt in or open from the side. Many double-hung windows now come with tilting sashes so both interior and exterior glass surfaces can be cleaned from inside the house.

Function. Tempered glass is required by code for certain applications, such as glass doors and some window installations with low sill height. For more extreme conditions, such as coastal environments, consider laminated impact-resistant glass designed to withstand hurricane-force winds and the impact of airborne debris.

Hardware. Some manufacturers offer improved hardware for crank-out windows such as casements and awnings — specifically, collapsible or low-profile handles that don’t interfere with blinds or other window coverings. Others offer a variety of style options for latches and locks. To be safe, ask about these and any other convenience features before the units end up in your walls. Also, try the hardware in the showroom. Does the window lock, unlock, and open easily? This test gives you a feel for the window’s usability and its overall quality as well.

Cost guidelines:
Broadly, vinyl and wood are the least expensive, fiberglass costs more, and clad windows are even more. That said, a general price range for an average size (30-inch by 48-inch) window is $100 to $200, which will be higher in urban areas.

More featuresólike tilting versions and higher E-ratingsóincrease the cost, although sometimes as the price and quality increase, more options are included. Differences in the up-front purchase price of a window may eventually be offset by other factors. Energy efficiency and a no-maintenance exterior will offset the up-front cost difference over time. Second, installation and labor costs could actually be higher for an “economy-grade” all-wood window, if you factor in charges for painting, and how much sooner you may have to replace it than a window made from more durable material.

One way to keep your window costs from rising is to avoid special orders. Try to work with standard sizes from a manufacturer, and select from the standard styles and features that your local retailer stocks.

Update your older windows

Windows can add a lot to a home’s character. But if they’re old and worn, they can also add to your heating and cooling bills.

From Better Homes and Gardens.

In older houses, faulty windows can account for a third of the total heat loss in winter and as much as 75 percent of interior heat gain in summer. Look for the following telltale signs that a window has lost its effectiveness:

  • Stand inside your house on a windy day with a lit candle near the window’s operative edge. If the flame flickers or goes out, your weather stripping might be damaged.
  • During the winter, if a window develops ice buildup or a frosty glaze on the interior of the pane, the ventilation in your home may not be adequate. Another possibility is that your window may not be providing enough insulation value, a situation that can make your heating bills soar.
  • If you need to prop open your window with a book or a stick, the window may have lost its functionality.
  • Sit near your window. If you feel cold air coming in during the winter or warm air during the summer, your windows have little insulation value. This means you’re paying more to heat and cool your house to compensate for the exterior air entering your home.
  • Do your windows get fogged with condensation? If so, you may have a seal failure and need to replace the glazing or the entire window.

In some cases, replacing broken panes and tending to loose or missing weather stripping may buy some time. If your windows are old and ill-fitting, however, you need more than stopgaps.

Replacement window options:

Wood is the choice of most homeowners. Wood is strong, insulates well, and has natural appeal and a warm look. It needs exterior maintenance, and interior surfaces can be painted, stained, or finished any number of ways.

Vinyl windows do not need to be painted or stained?a plus on the exterior. They offer good insulation value and strength, making them a viable alternative to wood.

Aluminum windows have a stronger frame but poorer insulation than wood or vinyl. They’re fine in areas with a mild climate, and are also used for commercial applications.

Fiberglass combines the higher strength and stability of aluminum with the insulating properties of wood and vinyl. Fewer options are available at this time, as fiberglass is just beginning to show up in the window market.

Combination windows are available with wood on the interior and vinyl or aluminum on the exterior, combining the look of wood with a low-maintenance exterior material. This is known as “cladding” (as in vinyl-clad or aluminum-clad).

Features to consider:

Energy efficiency. Almost any good-quality window available today incorporates two pieces of glass with a sealed airspace between then as a buffer between indoors and out. Some windows are even triple-paned. You may have the option of argon gas instead of air between the glass to further the window’s insulating abilities. Most window manufacturers also offer such options as low-E glass, which reflects heat and screens out the sun’s rays.

Design. Windows are available in shapes ranging from quarter rounds to ovals. Consider an arrangement of smaller windows instead of one large one, or vice versa.

Ease of installation. The easiest type of replacement window is a frame-within-a-frame design that can be installed in an existing frame without disturbing walls or trim work. Some are sold in kit form, complete with hardware, for standard sizes. If your original windows have divided lights or panes, look for multipane replacements or snap-in grilles that match glass dividers on the old units as closely as possible. If your windowsills are rotting or damaged, however, you’ll need to replace the old frame as well.

Ease of maintenance. Weather-resistant materials will reduce your regular maintenance; vinyl or aluminum-clad exteriors need no painting. For ease of cleaning, choose windows that tilt in or open from the side. Many double-hung windows now come with tilting sashes so both interior and exterior glass surfaces can be cleaned from inside the house.

Function. Tempered glass is required by code for certain applications, such as glass doors and some window installations with low sill height. For more extreme conditions, such as coastal environments, consider laminated impact-resistant glass designed to withstand hurricane-force winds and the impact of airborne debris.

Hardware. Some manufacturers offer improved hardware for crank-out windows such as casements and awnings — specifically, collapsible or low-profile handles that don’t interfere with blinds or other window coverings. Others offer a variety of style options for latches and locks. To be safe, ask about these and any other convenience features before the units end up in your walls. Also, try the hardware in the showroom. Does the window lock, unlock, and open easily? This test gives you a feel for the window’s usability and its overall quality as well.

Cost guidelines:
Broadly, vinyl and wood are the least expensive, fiberglass costs more, and clad windows are even more. That said, a general price range for an average size (30-inch by 48-inch) window is $100 to $200, which will be higher in urban areas.

More features?like tilting versions and higher E-ratings?increase the cost, although sometimes as the price and quality increase, more options are included. Differences in the up-front purchase price of a window may eventually be offset by other factors. Energy efficiency and a no-maintenance exterior will offset the up-front cost difference over time. Second, installation and labor costs could actually be higher for an “economy-grade” all-wood window, if you factor in charges for painting, and how much sooner you may have to replace it than a window made from more durable material.

One way to keep your window costs from rising is to avoid special orders. Try to work with standard sizes from a manufacturer, and select from the standard styles and features that your local retailer stocks.

Earth Berming Or Burying The American Ingenuity Concrete Dome House

The Ai dome lends itself very well to earth berming because of the strength of the dome shape and the totally concrete exterior wall, with no materials to rot. Our domes have been bermed with as much as four feet of backfill. However, if you earth berm your dome, we recommend a drain system (French Drain) to draw water away from the foundation. Plans for this drain system are included with our basement plans.

Can your concrete house be bermed higher than four feet? The American Ingenuity Geodesic Dome could be bermed higher or even buried, but we do not recommend it because the additional expense of labor and extra concrete would probably not be worth the gain. A dome or a structure that is not buried would never have to withstand loads greater than 100 lbs. per sq.ft. If a structure is buried the earth could put loads in excess of 500 lbs. per sq.ft. and we do not design our standard dome for those extreme conditions that would not normally occur.

Four feet is the maximum height of back fill that can go back against the dome. Back fill higher than this would cause more expense and complications than is likely to be worth while. Consider landscaping with plants to enhance the appearance that you want.

I would like to completely bury the dome. Is this possible?

Yes. Ai will need to hire a local engineer to review your soil report and provide designs for our CAD department to incorporate in your plans.  Once the dome kit is assembled, then vertical and horizontal rebar is installed and the concrete is gunited onto the entire dome surface the number of inches recommended by the engineer.  To support the weight of the additional concrete on the dome, supports may need to be installed to support the dome exterior.  His fee is based on the size dome and the amount of fill that will cover your dome.

A dome like an arch, increases its effectiveness as it is compressed so it will support partial earth berming or any snow load. We have fortified our reinforced concrete with space-age fibers and special admixtures, as well as galvanized steel. As the panels of the dome are assembled, the beveled seams between them are concreted, creating a network of interlocking arches of structural beams.

When the dome is bermed, a French Drain is installed around the base of the dome. The steps are:

  • Cover any part of the basement wall that will be in touch with soil with a tar emulsion (designed for this purpose). This waterproof coat should extend down to (and if possible, under) the polyethylene vapor barrier.

  • If you wish, you may add additional waterproofing. Apply roofing felt over the tar emulsion, overlapping the edges 6″ and sealing the felt with more tar. Place the roofing paper over the outside of the vapor barrier to shed water. Then, give the whole wall one more coat of tar. This extra investment will provide a superior measure of protection against moisture. Please, don’t cut corners.

  • Place a perforated drainpipe (at least 3” in diameter. – 4” diameter. For long lengths), holes down, into the gravel bed. The pipe should be below the floor level and drop 1” for every 8’ of length. This discharges water into an area lower than the dome itself and allows quick drainage away from the building. Lay pipe in the gravel bed and cover gravel with two layers of roofing felt to prevent dirt from penetrating into the gravel.

  • Backfill the entire area.