What do you plan to do with you dome, what size, what
kind of construction, weather etc.?
The pvc hubs with wood constructions are the least
Aluminum hubs will be approx twice price of pvc.
Quick connects are ideal for repeated
dissassembly/assembly and use various hardware and
hub modifications to make connecting quicker, for wood
The thing with domes is the synergy effect or shared
stability between parts, so no part in itself has to
be super strong. The pvc is plenty strong for most
see # 5,996,288
The steel connector plates [Star Plates] are still available for
the icosahedron dome. I honestly believe my connector
hubs are an improvement, for many reasons. The main
one is easy opption of the "perpendiclar bisector"
[X1] struts, and also all hardware is included in the
Connector Kits. The Icosa-Dome X1 Connector Kit for 2
x 4 wood is $144 + $15 UPS.
There are other low cost domes, such as the
"Tetra-Dome X1 + VBO" that a standard door can be used
with, and the oct-tet pyramids. Four 4 x 8 ft sheets
can cover the octa pyramid with 8 ft edges (8 x 8 ft
base) that is ideal for polycarb glazing. Another 2
sheets can cover a 2 ft Vertical Base Option.
It's always good to hear from people who can think
out of the box mentality and interested in domes.
About the Star Plates. It's a pretty good deal
i.m.h.o. but limited in applications. I have an older
set, but never put it together. The instructions are
good too. I wrote about it some on the domegroup.org
Here are some points to think about-
1. You buy lumber and saw 90 degrees ends or keep as
you but it, ~8 ft, and drill through the thin 1-1/2"
end for carriage bolts that you need to purchase, 50
5/16ths 4-1/2" bolts/nut/washers. (THis posssibly is a
big point of weakness - hole drilled through the
2. The new Starplates have 10 holes, so you can make
the Perpendicular Bisector struts, equal to my
Icosa-X1 design, but with different connection method.
You would need the Simspon metal 4-way connector or
similar too, + more bolts. My Icosa X1 Connector Kit
for 2 x 4s is $144 + $12 UPS.
X2 - $243 + $20 UPS
X3 - $486 + $30 UPS
With the Connector Hubs we use, you saw the angled
ends with a power saw, drill a pilot hole in each end,
so there is some initial measuring to do, and drill
short pilot hole for 5/16ths lag screws placed through
hub holes as described in my "Improved Dome Joint"
Patent. The pvc hubs are plenty strong, and the
compression strength of the Arch in a 3-way grid is
created. Several Dome Home companies use variations n
the cylinder connector method.
A nice feature is versatility, in that any and all
dome types (and other things) can be made with the
Connector Hubs, relatively inexpensively.
For the Icosa Dome, X1, X2, and X3 types can be made.
Do this for adding struture and strength and struts
for attaching roof materials.
The Triakis (shallow pyramids) Icosa can be made, and
Rhombic Triacon with its large flat faces, so the
Icosa shape becomes hidden among the pyramids.
Icosa-Dome of useable size has ~8 x 8 x 8 ft
triangles. For covering with panels made from 4 x 8
sheets, use the X1 subdivision is least. The 4 x 8
sheets are cut diagonally to make right triangles that
can be nailed right on to the 2 x 2 or 2 x 4 struts.
inceases interior space, and possibility of a standard
rectangle door retrofit into a lower hexagonal area.
But for a "Garden Shed" the Tetra Hut, Tetra-Dome X1
and Cube-Octa Simplified dome are also good.
Thus far we have donated a Garden Dome 3 20 ft to a
childrens home in Arkansas, and the 25 ft Octa-Dome 6
to the Green Corn Project in Austin. It's not yet
complete; their community garden location is going to
have homes built on it so they will need a new place
for the dome. see
Tetra - Dome X1 + Vertical Base Option -
Yes the GD4 is a great dome too, for a half sphere
dome. Use X1 for roof support and for covering with
Around $7-10,000 for the 2x4 to 2x6 frame kits 35 - 40
ft. with aluminum connectors and galv. hardware,
shipping ~$1,000 - $2,000 from Austin.
Alum. connectors will have an industrial epoxy coating
The GD3 EZ X1 will be a good dome in the 30-40 ft
range. One is being built in NC for a large
greenhouse, 30 ft.
72 feet diameter is the largest size you can go with
the Garden Dome 6 = 6 frequency type dome, and keep
the longest strut under 8 ft. You will need to go with
higher frequency to acheive dome size with triangles
with longest strut 8 ft.
It's no problem to make the higher frequency domes.
It's just that I never imagined anyone would need one.
The size limitation would involve many factors such as
strength of the [wood] struts, weather conditions,
covering, type of hub connectors, function of the
dome, how tall it needs to be. In all cases I have a
disclaimer that basically says, the domes are
(legally) not certified for anything in particular as
for usage. In practice the domes have functioned
beyond expectations, with pvc and aluminum connector
hubs, and standard size construction lumber. Many of
the dome designs have not been built, and none that I
know of with wood, larger than 30 ft.
w/ 8 ft max strut limit:
7 frequency icosa dome - 85 ft 246 connectors - 39 ft
height. 10 of 21 rows of triangles (could be shorter).
Connector Kit cost - sch 80 pvc connectors for 2" x 4"
or equal wood - $2,700 + shipping
8 frequency Icosa Dome - 97 ft
10 of 24 rows of triangles
Height - 34 ft.
hub qty = 261
Cost - $2800 + shipping
Star Connectors allow you to use pvc or other
materials for the dome struts. There is more measuring
details involved, and hole drilling in the struts.
Star Connectors are comparable in labor work required
to the complete steel tube frame, but less weight and
less for shipping. The 3/4" Icosa Dome Star Connectors
[50 separate pieces (= # of struts X 2)] is $218
including UPS see NL# 23
The complete 3/4" tube Geo-Sphere , 7 ft diameter is
$1200 + UPS. With smaller size, and/or 1/2" tubes,
Here's some info on the Tetra-Domes. With the
Tetra-Dome, there is the top half and bottom called a
Base Option which can be the geodesic triangled type
or vertical type riser wall type. With the Vertical
Base Option added to the Tetra-Dome top, height is
added making useable space, while keeping the 8 side
foot print for more floor area than the square foot
print of the geodesic Base Option.
The Geodesic Base Option adds significant height a
certain measure relative to the dome diameter, while
the height of the Vertical Base Option is fully
adjustable to any practical height, say 2 to 8 ft.
Both types are adaptable to the Tetra-Dome Matrix
design for adding on additional units by connecting
openings at square areas. A screw/nut/bolt and metal
fitting will connect the hub-to-hub mating junction
where two tetra-dome units of the Matrix connect, for
The T.D. can have both the X1 or X2 (or, X1+1)
subdivisions, and joined in the Matrix with pyramid
point - to - point struts.
For the 20 ft diameter, measured across opposite
pyramid points- You can do this with 8, 10, and 12 ft
lumber. The Cube or longest struts are nearly 12 ft.
Compare to the ~17 ft diameter with the 10 ft long
For the 20 ft diameter, you need the X2 boards and
extra hubs and hardware to reduce triangle size, for
supporting the covering. On my dome, the X1 boards are
2 x 4 and X2 (X1+1) are 2 x 2 = 2 x 4s cut in half
lengthwise on a table saw.
Anchor with cement poured in a hole in the ground,
and anchor screw or rebar into the bottom hub where
anchor holes are located.
Use the 13 mil Super Poly Covering. 10 x 150 ft
should do the job. ($345 + $35 UPS) Use a board or
other rigid lath over the installed poly, or
Cinchstrap, and Polyfastener for windows / removeable
Windows will give you ventilation. One large and 1 or
2 small windows is plenty. You might need some shade
cloth in the summer.
I used a garden sprayer to apply oil wood
preservative, then a few weeks later brushed on an oil
based white stain. The good quality white elastomeric
on new dry wood does a good job too. It should last
10+ years. With clear oil preservative, just repaint
or respray periodically.
I have Tetra-Dome X1 [top] sch. 80 pvc Connector Kit
for $169. For X2, additional 4 hubs and hardware
including 4-way Strong Ties, $244. Add 15% for UPS
We can do the whole 2 x 4 dome frame and send to you
via Roadway. $1600 + shipping approx. $500 depending
on destination point. Super Poly Kit with hub covers,
You could do a Garden Dome 6 type, 555 struts that you
can make with the Connector Kit. Make it ~48 ft to
keep struts under 5 ft, and use 278 2 x 4 x 10 ft
boards. You can delete the lower level of triangles
for a shorter dome, easier to heat. You might want X1
subdivision struts to support the covering under wind,
snow and ice. $2,205 for the 196 sch. 80 pvc hubs and
$3,167 for X1 hubs and extra hardware for 250 added X1
struts. If you make 55 ft dia., some struts are closer
to 6 ft.
With the 6 frequency Icosa Class II dome, you have 410
struts, and only 146 Connector Hubs. Struts are in the
5.5 to 7 ft range for the 55 ft diameter.
So will be $1642 for the sch. 80 pvc hubs for a 2 x 4
dome; and X1 hubs and added hardware, $2,357
Add 10% for UPS shipping. See
For precut polycarb. Thermoclear type twin-wall. Would
be approx. $25,000 for the triangle glazing panels,
installation materials and labor not including
You can use standard lumber size for redwood. 2" x 4"
would be ideal.
For venting, you can have the cupola with automatic
thermally actuated vents, and/oror electric exhaust
fans with thermostats in the cupola and/or mounted in
the glazing triangles.