You can use pressure treated wood but if you sink them into the ground they will rot quickly. I am currently dealing with that on my wooden screened room (inherited it with the house) You can get ground level concrete pilings to mount them on vs. in the ground.

I know peeps who swear that you can paint or dip the bottoms of your PT post with roofing tar , let it dry and they will last 20+ years in the ground..

As soon as I can ask my brother exactly which tar, I will post the particulars here.

Also, after the roofing tar dip, when you put the concrete around the posts, mound the concrete so that water runs off and does not stand around the posts.

Gary, I was wondering how you plan to control the temperature?

Stick with aluminium. Go find your local aluminum recycling company ..same place where the aluminum can people sell their daily collection. Aluminum contractors also recycle screen rooms and swimming pool enclosures etc etc. Aluminum prices are way down. Times are tough you can find all shapes and sizes of aluminum at the recycle place. I bought
a nice ladder there a few months back for pennies on the dollar compared to Home Depot. My friend bought a 12 ft. aluminum boat for $98.00.

Hi
have been thinking about this for a long time and trying not to make the same mistakes I made in the past lol
I guess what really needs to be done is make up a budget with the various materials Right away I can see that redwood and cypress are out of the question while PT pine is the only choice left. I suspect even that would come very close to the cost of aluminum so there goes one advantage for sure . Feel certain an aluminum frame would need at least a concrete footing which I suspect would cost as much as the framework . Another choice I'm checking into is vinyl coated PVC. or structural fiberglass.Another whole can of worms is city ordinances .Feel certain they won't let me build as tall as I want nor as close to the property line. Have a few ideas so don't think that stops the project. But obviously should get a clear idea of the problems.
Vireyafla. I know a whole bunch of ways that don't work lol Have been experimenting over the years in the present structure and I think I have a couple of ideas that solve most of the problems that don't involve winning the lottery as step one lol Gee you'd think temp controls would be a snap in ten lol You have any ideas?? Thanks everyone for the suggestions.!! gary

Gary, what about the metal piping that chain link fences are made from, for the structure - I think it comes in various diameters and you can get all those elbow pieces to connect the lengths.
I have been trying to figure out the temperature problem with regard to keeping it at least above 40F in winter and all I can think of would be the double walled lexan panels - but they need to be easily removable - would there be a possibility to have sliding panels as in a sliding glass door, so that they could be slid to one end when not needed?

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That would be a possibility .Do they come in square shapes rather than round??. Squares make it much easier to attach other materials such as lattice to the frame. I suspect they would cost more than aluminum? They also will corrode though it takes a long time..
I have used lexan in two grades in the past. The cheaper stuff will craze and the more expensive grows algae lol They do make a "super " type stuff called Carbolite which is polarized and will automaticly darken at certain levels. Don't ask about the price lol Still could not be left in place the whole year due to heat gain.I'd bet it could be left in place for at least 3 months.
The frustrating part is that cold fronts are so temporary
in 10. Even on the coldest days the heat gain inside is more damaging than the cold .They usually last 3 days and are dead calm so you must resort to fans or remove and replace the panels daily. Then during summer you have no covering or use other panels covered with screen whatever.
This year is a great example low 30's followed by mid 80's You actually need two different coverings often in the same day.lol
My best compromise is Vinyl lattice which supports vines over the top.Prune back during winter. During cold fronts I place frost cloth over the top use a small themostaticly controlled electric heater. The heat is allowed to escape this avoids overheating the next day and can be left in place for the next night. This works fair IF the front is normal ,dead calm with brilliant sunshine the next day. If windy or cloudy leaves a lot to be desired lol Of couse there are cold spots but it is frost proof.
have been experimenting with using warm water. Since I'm a fish nut as well as a ponder I have 1100 gallons of water .Have found this can be easily kept warm and does effect the air temp but in the 30's 900 watts was not enough heat. I paniced and cut off the system when the water fell to the low 60's Save the fish or save the plants?? lol Moved the more delicate plants into the house,covered the pool with bubble wrap. So I didn't get to see the bottom temps of either setup. Last year the bottom was 40 and it worked beautifully . No work on my part at all. Might also add that during the summer I get a "cooling" effect from the water as well as a humidity boost ,probably too much ??
Since I'm thinking of expanding need a MUCH better way to control temps or at least take the edges off .
Moving a hundred plants is tough imagine moving 2/300 ??lol
Might also add that I keep tropical birds in there also. Normally I just move them into the house during fronts but this year the Honeycreepers are seriously building a nest!!. I opted for using an ifrared heater without moving. Seem to have done fine at least so far.
One of the main reasons I want to expand is to give them enough space to produce some offpring. So the design and management will be more geared toward the birds rather than plants but gee !! I love my delicates also lol gary

Honeycreepers! how wonderful - which kinds do you have?
I see your point with the heat build up and the lattice roof, but to really protect from the cold I think a roof covering is necessary and having to put a frost cloth on such a large structure as you are planning is a bit of a pain. I think that if you have the roof high enough to allow for cross ventilation, perhaps with some fans, a permanent roof structure would be better. The question is what to make it from? Have you tried the solexx panel?
I have friends in south Dade, way west of the turnpike, where it gets cold and they have had the best results with a permanent roof, fans for air movement- they put plastic up around the walls when cold weather is forecast and when it is cold they run their sprinklers all night with well water that is about 70F - no heaters required - this is for orchids. During the day time when it is hot they roll up the plastic and lower it at night as required.
Having to roll plastic up and down is a real nuisance though- I would like to know of some easier system of opening up walls by day and closing them at night, just for the few weeks that we get cold weather, in order to protect orchids.

Hi
I keep a pair of red legged Honeycreepers,Cyanerpes cyaneus they live like hummers but are actually members of the Tanager family. The male in full color is GORGEOUS especially when displaying. If I could raise a few clutches I could pay for the upgrading of the shadehouse lol. One of the few birds that can be kept with plants.
A permanent roof structure would be better ,besides the cold there is the problem of heavy rain. Okay for the plants not so good for the flowers. I was thinking about a gabled roof ,not only to act as a heat trap but to keep debris off as well as cats and squirrels maybe??
I fear I can't build over 10 feet but a gable might get around that. The higher the roof the more effective the fans, besides you need around 3 feet overhead for hanging planters.
You can fight with the cold or the heat. Cold is a much shorter battle lol.
I have found orchids a lot tougher than reputed. I grow cool down dry dends and Brassidiums which can easily handle into the 30's just no frost. Takes advantage of the normal cool dry winter. Even with an enclosure there is still an advantage to growing in containers besides being portable. Everything grows like weedslol so constant rearranging is necessary, easy in a pot.
I grow some understory palms that are rated at 60 for a low. Now that's really dreaming lol I keep them in pots and move into the house when necessary but what is my plan if they actually grow and get 20 feet tall?? lol
There is a post on the GH forum about maintaining a coolhouse in Florida. So far the posts say it can't be done lol gary

I am in serious honeycreeper envy - I have seen the purple and green in Trinidad and Ecuador and I think they have the purple at Butterfly World, but I did not know that ordinary people could raise them - that is really neat. Perhaps they would like to be able to migrate from your lattice roofed area(which I presumed is screened also) to your new roofed area when it is colder?
I think that you can be much more successful with orchids if you have a covered roof, so that you can control the watering when we have numerous days of torrential rain and protection from the cold is an added bonus. Are you talking about Joey palms? These would definitely need to be in your roofed section.
If you do a gable roof, what will you use for the roof and also what for the walls? That is what I am trying to figure out!

Hi
Yes it's still possible to get several species of honeycreepers.Even captive bred are available occasionally.
There are a host of problems with keeping and breeding them. I wouldn't even consider them without such a large area. Certainly not a "cage " bird. I keep a dedicated aviary but the wife insists on parakeets. You don't keep them with plants for sure. Since my other structure mainly houses plants ,Honeycreepers seemed like a natural choice.
Have tried several species of finches ,Waxbills being the most successful. For temporary heat I've always used infrared heaters located above the perches.
I use zoomesh cloth under the lattice to contain the birds but also keeps out the rats. A very serious aviary problem in Florida.
My main purpose for expanding would be to provide a more suitable breeding area for the noneycreepers but heck why not add a bunch of finicky plants?? lol
I'm still working on material for the structure lol I have tried many kinds of coverings for the present structure all of which leave a lot to be desired on a year around basis. When I repaired the hurricane damage went back to lattice only with the zoomesh ,vines provide shade
Covering with frostcloth during temps below 35, electric heater is used allowing the heat to escape . Much better than overheating the next day and can be left in place for the duration of the front. This means I can do without fans when temps are acceptable. Bear in mind that my ceiling is only 9 feet which means the heatgain is tremendous during sunshine without venting.
On the new structure I'd like to have 15 feet,then I could consider several types of coverings. I still suspect that there would be serious overheating problems but thought I'd counter that with removeable panels, At least I'd be able to keep them in place for a couple of months??
Fans would be out of the way but no solution to the rain ?? lol.
I'm working on a budget on what this glorious structure would cost though I guarantee no design would rely on airconditiong during summer.
There are various people on GW that keep SH/Gh's that they seem happpy with. I want something that doesn't require so much work to manage lol. So still seaching for that "perfect" covering gary