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The following article covers Strength & Inside Edition FAQ.

Exterior garage pineapple

Above is the 22′ dome linked to 34′ dome that were under construction when Inside Edition Visited

These Domes Went Through Hurricane Jeanne and Frances with no damage.

While the roof was blown off the house across the street


Q: When the reporter from Inside Edition visited, what dome advantage did they zero in on?

A: The theme of the segment revolved around the super strength of American Ingenuity’s prefab concrete domes and how the Ai domes withstand hurricane forces. The reporter and two man camera crew first went to Miami, Florida and interviewed the owners of an American Ingenuity dome that survived a direct hit from hurricane Andrew. Views of the Menendezes’ beautiful interior were shown but the inspiring stories of the horse trailer and tornado slamming the dome got edited.  To view the Inside Edition video, view Inside Edition. Once you are on the page, scroll down and click on the second video which is the Inside Edition video.

They then drove up to our corporate offices. The segment went on to show our five dome complex including the  component panels being made in the factory.

The next stop was to view our domes under construction in Melbourne, Florida, a 34′ dome linked to a 22′ garage. Also of interest was the interior metal framing and metal floor joists.

The program director had previously asked us for a way to illustrate the domes’ ability to withstand hurricane force winds. Short of calling up a 200 mph wind and filming the real thing, the next best option is a computer finite analysis. The computer simulated a force equal to 230 mph winds. Our dome stood rock solid. In fact, to see the movement in the dome, the deflection had to be magnified 50 times. A square structure was also modeled but it collapsed with 150 mph winds.

A completed dome home was the next stop. After videoing the house and the dog dome, the reporter, Stephen Gendel, asked for an egg. While on screen he took his best shot at squeezing it to death. They departed shortly thereafter knowing that they had a good story and I can tell you with certainty, they were impressed.

About a week after the program aired we got a call from the New York office. They specifically called to tell us that they had received a flood of calls from people trying to get in touch with us. For viewers to call us directly they had to figure out the city and area code on their own. One lady reported that the long distance information operator knew our number by heart.

Q: Does American Ingenuity 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.

Q: What wind loads will the dome withstand?
Because the structure of our dome is steel reinforced concrete it is incredibly strong and easily enhanced to accommodate unusual requirements. The standard design will accommodate up to 225 mph. winds and category 4 tornadoes.  To view information summarizing Ai dome and hurricanes, view Hurricane Recap.

Two of American Ingenuity’s domes in Hawaii went through a 6.6 earthquake in 2006 and suffered no structural damage. To learn more about the earthquake, view ABC News Link and on MSNBC News Link.

The Ai dome design has proved itself by withstanding Hurricane Andrew’s 165 – 200 mph winds, a tornado that rolled up a steel horse trailer and slammed it against the Menendez dome, four hurricanes in 2004, 6.6 earthquake in 2006, sub-zero temperatures and heavy snow loads of the Northwest Territory of Canada, a 30″ in diameter 115 foot tall hickory tree impact, a lighting strike and many other conditions since 1976.

More about steel horse trailer impact: American Ingenuity warranties their concrete domes against 225 mph winds and F4 tornadoes. Since our dome kit manufacturing business started, Ai has sold 800 kits into 47 states and thirteen foreign areas. Since then Ai has not had any of our clients domes have any damage due to hurricanes or tornadoes except for one dome during Hurricane Andrew. During Andrew a tornado slammed a two wide metal horse trailer against  a 45’ American Ingenuity Dome.  A riser wall of the dome ended up with a hairline crack and a missing chunk of concrete. The dome owner caulked the crack and mixed up fiber concrete and filled area where the concrete was broken and painted over the area.

More about the tree impact: There was no damage to the Brack’s 48′ dome after winds in excess of 75 mph hit North Carolina in July of 1996. The real test came when a 115′ high, 30″ in diameter hickory tree was blown over and fell on their dome. The impact broke a 10″ diameter branch. The tree slid off and landed on a deck post driving it and it’s 16″ square concrete footer 6″ further into the ground. The insurance agent who inspected the damage to the deck conveyed his amazement about the dome’s strength with this comment, “If that had been a frame house the tree would have ended up in the basement!”

More about the lightning strike: American Ingenuity’s 45′ office dome withstood another one of nature’s most powerful forces, a LIGHTNING STRIKE. The lightning hit the outer edge of an entryway and the only damage it did to the dome was to knock off a handful of concrete at the point of impact! A couple of our computers have not been the same since, but the cost to repair the dome did not exceed $30 in materials and labor.

More about heavy snow loads: In 1995 Howard and Mary Carroll visited Robens and Tom Napolitan’s dome.  Robens was enthusiastic, but Tom was not. Tom explained to the Carroll’s, “its all HER idea, I didn’t want a dome.” Mary Carroll phoned the Napolitans in 1996.  Mrs. Carroll said you couldn’t keep Tom quiet this time.  He had nothing but wonderful things to say about the dome and had completely turned around about the wonders of living in an American Ingenuity dome…..ROOFS HAD COLLAPSED in their area under several feet of snow, but NOT HIS DOME! Tom’s turnaround sold Mary and her husband on an Ai dome.

Q: Have you performed a load test on your panel?  To view the load test file, view Load Test.
Yes, in October 2000 Ai performed a load test on one of its 48′ dome building kit’s component panels. The test was performed on our largest house panel using the standard 7″ thick E.P.S. insulation, 3/4″ thick concrete exterior reinforced with steel mesh and fiber reinforced plaster on the interior. The strength of the component panel can be best be determined by measuring the deflection of the panel as a load (weight) is applied in increments. The panel was placed horizontally. 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 the sand could be spread evenly, providing a uniform load.

The deflection was measured in the center and six other locations. At all the measured points a steel ruler was attached to the panel extending high enough to be visible when the panel was fully loaded with the sand. A surveyor’s transit allowed us 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 more brave; so we cut through the interior plaster on the bottom of the panel. Even then the deflection was less than 3/16 inch.

We 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 on the panel and 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.

A 120-mph wind will exert a pressure of 30 lbs. per sq.ft. on a vertical wall and a snow load exceeding 50 lbs. per sq.ft. is rare. Our panel withstood 170 lbs. per sq.ft.

Q: The prefabricated panel concrete is not that thick, why is American Ingenuity’s dome so strong?
The panel concrete does not need to be thick because the strength comes from the triangle shape and the steel reinforced concreted seams which are about 5″ wide and 3″ deep averaging two thick concrete. Engineers tell us the seams act like steel beams and transfer any stress all over the dome instead of containing the stress in one spot.

Framing Of The American Ingenuity Dome

How are interior walls attached to the dome shell? Where ever an interior wall butts up to the dome shell, a metal stud is glued against the shell with spray foam.  This way there is a 2×4 cavity to screw the tops of the metal studs into and gives an edge on the metal stud to screw the wall board to.  Then an elastomeric caulk or resin paint fills in the area where the shell meets the wall board.   Or install a trim board.

How are second floor joists supported?

  • Most often the second floor joists are set on top of the first floor load bearing walls, the same as in conventional framing.  In areas where additional support is needed, or where there are no first floor walls, microlam beams can be installed and or parts of the second floor may be hung from the dome shell in specific locations by anchoring a 5/8” threaded rod vertically into the concrete of a seam.
  • Some of the weight is suspended by threaded steel rods which anchor into the concrete seams and extend vertically down into the dome.  Over 3,000 lbs. can be supported by a 5/8” threaded rod suspended in one of the concrete seams.   The location of the suspension rods is determined by your floor plan selection.  The Building Plans will show the suspension rod’s positioning.
  • The suspension rod with nut sets on a 3”x6” steel plate, which is embedded in the concrete seam. The seam is reinforced with #4 rebar & two layers of galvanized steel mesh. These suspension rods and plates can be purchased from American Ingenuity.
  • After the first floor is framed in and the drywall is attached to the interior framing, the first floor walls make the second floor very rigid.
  • For areas that require bracing plywood is installed in the framed entryway walls and on the first floor and second floor interior walls.

What is needed to frame first floor walls?

Materials And Tools:

  • Door, folding closet door, bath tub and shower module dimensions
  • 2”x4”x 8’ pressure treated lumber
  • 2”x4”x8’ standard lumber (kiln dried Southern Yellow Pine or White Wood for all studs including load bearing walls. For economy you can use 92 5/8″ long stud lumber for load bearing walls, they cost less than standard 96″)
  • 16d common nails
  • carpenter’s pencil
  • 2 saw horses
  • electrical circular saw
  • chalk stick
  • Great Stuff Minimal Expansion Foam Sealant
  • nailing apron
  • 2 ½” fluted masonry nails (or a rented handheld, hammer triggered concrete nailing gun)
  • Shells and concrete nails for safest, cleanest, fastest attachment of bottom plates.
  • Doors should be ordered from the supplier. Plan ahead as there may be delivery time involved. Doors on hand provide you with the exact measurements for rough openings in framing.
  • Select bath tubs, shower modules and such now, and obtain framing dimensions.
  • If you plan to install an oversized item such as a Jacuzzi, which is wider than a standard door opening, put it inside the area to be framed right now. Keep it in its shipping carton for protection during wall framing.

Build The Internal Walls – See your Building Plans for exact specs.

  • The exact location of the rough plumbing stub outs determines the actual location of the internal walls. If the stub outs were moved a bit during concrete pouring, the wall location has to be adjusted accordingly and may differ slightly from the plan.
  • Measure wall dimensions, cut plates and studs. Wall height from concrete foundation to top of top plate to be 8′-1″.
  • Bottom plates to be pressure treated. Bearing walls to have double top plates. Top plate members must overlap 24″ at breaks.
  • Rough door openings to be door width W+2″ and door height H+2″ (door rough height is generally 80″, unless a nonstandard door will be installed.
  • Assemble the wall component lumber by laying it out on the flat concrete floor foundation and toe-nailing it perfectly square.
  • Double check dimensions and squareness and, if satisfactorily, righten the wall to the vertical position.
  • Move the wall into its position to where it touches the wallboard of the dome shell.
  • Mark the location of a wall stud on the wallboard
  • Carve out a 3” deep cavity into wallboard and foam and extend a 18” long 2×4 cut off upwards from the wall stud into the cavity. Attach the stud extension to the stud with deck screws and fill the cavity around the 2×4 in wallboard and EPS with expanding foam. This makes for extra stability of the wall at the dome shell junction.
  • Finally, inject Great Stuff Minimal Expansion Foam Sealant into all open spaces between wall lumber and wallboard at the dome shell.


  • Gather the necessary materials and tools.
  • Simpson LS 70, Simpson LUS 28 (can be purchased from Ai.)
  • Steel U-channels 3”x 1 ½” x 6” and suspension rods (purchase from Ai.)
  • 5/8” nuts and washers for suspension rods (purchase from Ai.)
  • Joist lumber (2”x 8” or 2” x 10”, per plan)
  • Edge beam lumber
  • 16d x 3” and 16d x 1 ½” nails
  • Framing square
  • 25’ measuring tape
  • Hammer
  • Level ( or rotary laser level tool)
  • Carpenter’s pencil, black felt pen
  • 2 saw horses
  • 8’ and 10’ ladder
  • Circular saw
  • 1 ea. open and box wrench for 5/8” nuts
  • Tie wire
  • Carpenter clamps
  • 1” wide wood chisel
  • Utilize cleaned up form boards of the same size as joist sizes in Plan S-5.
  • Bend support rods into plumb position as good as possible.
  • Measure distance between suspension rods horizontally at the dome shell not at their lower end.
  • Suspension rods tend to point uncontrolled into off plumb directions before they are connected to the second floor edge beams.

Build The 2nd Floor Edge Beam – Refer to your Building Plans as they take Precedence.

Measure and cut edge beams according to plan, using the measurements obtained from between the rods.

Outside of the beams are slightly longer than inside Length. (see detail plan S-5) All perimeter edge beam ends are cut at an angle to achieve maximum support surface from the supporting U-channels.

Edge beam bottom corners are notched out 1 ¾” high from bottom of edge and 3 ½” from beam ends, where they will rest on the U-channel. Secure temporary, but effectively for safety purposes, the edge beam to both the U-channel AND to the rod with tie wire.

Mark all suspension rods all around with black felt pen at 8’- 2 ¾” up from the concrete floor.

Slide U- channel from bottom end up the rod (channel legs pointing downward) until its top surface is at the level of the mark. Slide and turn a washer and a two nuts up the suspension rod thread to support the u-channel in its position. Later secure nuts with locktite. Repeat this with all suspension rods.

Nail two boards of lumber together to form the first edge beam. Lift the beam onto the U-channels, half of the U-channel supporting the Edge beam as shown at SUSPENSION ROD DETAIL 2 on plan S-6.

Continue around perimeter by placing and temporary securing the next edge beam.

Nail a Simpson LS70 connector to the outside joint of the two beams, after hammering the angle of the LS70 more open to fit the angle of the joint.

Continue to complete the edge beam perimeter.

At this construction stage, some components are loose and flexible and prone to slip and fall at the slightest disturbance. Be extra careful. Declare the area under the beams off limits and have everyone wear a hardhat.