Underground greenhouse support posts, wood preservation, groundwater drainage and more!

Hi Mike and everyone else!

Thanks again for being here. Just watched some Major Miracles with my housemates. We all laughed and also thought you were saying some truthful things.

I have many questions for you about my greenhouse and don't expect answers to more than one...

My water table is high and I want to limit the depth I need to put wood into the ground. I also want to increase the strength against hinging. Instead of doing 6x6 posts as you recommend in your book I am considering using Stanchions, as shown in the method on this link: http://www.familyhandyman.com/DIY-Projects/Outdoor-Projects/Backyard-Structures/Retaining-Walls/how-to-build-a-treated-wood-retaining-wall/View-All

Do you think this would make a solid foundation (I'm in the same climate as you)? I'm also considering just doing Stanchions on the North wall that is to be 12' tall with larger support trianangles (roughly 6-7 feet). Then burying posts per your recommendation but adding anchor triangles to their backsides on the remaining sides. There will be horizontal cross supports that span the width of the greenhouse as well at 8' height. Any thoughts?

I read recently in "Biolshelter Market Garden" by Darrell Frey (great book!) they used a mixture of beeswax and turpentine painted on as a wood preservation. In your greenhouse book you don't talk about rotting as a large issue if you use the PSP method. Have you really had no issues with rot? Anyone have experience with homemade and non-toxic wood preservation?

I have been considering adding drain tile around the shoring to eliminate water issues but don't have the appropriate slope to "daylight" the pipe. I plan to angle the soil away from the greenhouse, and do the V shape mound on the North to divert surface water. Any suggestions for draining ground water away from structure?

Do you know any polycarbonate dealers in the North Idaho area or should I just order from Sundance? Anybody want to get in on an order from Sundance to cut shipping costs?

Thanks!

-Alan

HI everyone, I was hoping for some advice. I am new to green housescreen and I have a defunct swimming pool in my back yard. It's actually a hole with a plastic bag in it. I want to pull the liner out and build a greenhouse over it. My son said just be careful the walls don't collapse. I don't know what is currently behind the liner but I think I will need to build a retaining wall around the inside. Any suggestions? Thank you all in advance

The in ground pools I have seen have a retaining wall under the plastic liner. I don't think the walls collapsing is a serious concern, but do be careful. Your pool may differ.  Besides, you dont know the condition of that wall... if it exists. Is there a drainage system in the pool?  As you work on it, you may experience rain. You need to have a way of getting rid of the water.  The drainage will be needed as you use the greenhouse as well.  

https://gardenpool.org/

Hey there,
Garden pool does this sort of thing all the time. They're based in Mesa, az. They may have advice. Lots of photos for inspiration.
Hope it's helpful.