Do the same thing with PVC pipe - and fittings - it will cost less...

Run a 3 inch in diameter pipe on the ground - at the end of the pipes
put "T" fittings facing up -

On the ends of the "T" fittings that are not needed for more length put
clean out plugs.

In the verticals of the "T" put in standard 3 inch pipe

If you have to go more than one pipe length high use an "X" or "T"
fitting to allow you to tie the verticals together.

When you are high enough

At the top use a "X" or a "T" fitting to again tie them together and to
allow another short pipe to run up to a standard 90 degree elbow. Run
pipe across the top of the green house.

Hang your shade cloth from it.

As you build the frame, fill it with water - this will add the weight
that you need to keep the wind and the weather from moving it.

PVC is cheaper than metal, cuts with a hand saw and can be force fit
without glue.

If you plan to leave it up year round - then glue the daylights out of
the frame - since mine has to come down in the winter (Michigan) - it is
not glued at all. I have to add some water every couple of weeks.

DO NOT add enough water to fill the pipes that cross the top of the
greenhouse - the sag is something you do not want to see.

Doug

In article ,
(Lori Siegmund) wrote:

Tom, Ray, Doug,

Thank you for your input. Sounds like I am envisioning the same thing
as all of you have described.

An alternative that was proposed to me by a contractor friend was
something like this:

__________
| /\ |
| / \ |
| / \ |
| | | |
| | | |
_____|_|____|_|________


The inner lines of this crude diagram is the gh. Bottom line is the
ground. The two lines parallel the the sides of the greenhouse are
metal poles (think flagpoles).There would be four metal poles (one
cemented in to the ground in each corner of the gh. The height of the
poles would be one foot above the roof peak of the gh. There would be
metal cable connected between each of the poles at the top. The each
side of the shade cloth would be attached a line of cable.

If you were looking down from a very tall tree, the shade cloth would
hang flat; suspended over the gh like this:
___________
| |
| |
| |
| |
|_________|

Essentially, this is constructing a shade structure around the gh. I
suppose I could then hang panels to shade the sides of the gh from the
same cable that is
helping to suspend each side of the top panel above the gh.

Have any of you seen this done? It sound extravagant and more
expensive to do than the other options presented by this forum.

Also, Tom (from Walnut Creek, CA) do you leave your shade cloth in
place all year around? What type of gh do you maintain (cool,
intermediate, warm) and what type of orchids are you growing?

Thanks!
Lori Siegmund