I had a greenhouse back when we lived in Tennessee over a decade ago and since then we've done without, and this year we want to actually make our own greenhouse again.

I have a metal shop (30x20 in size) that has a perfectly south-facing wall, and my plan is to make a "lean-to" type of attached greenhouse. I want it to be nice, and I expect it to last a very long time, so I'm not going to spare much expense.

I'm currently planning for it to be about 24 feet wide and 9 feet deep.

One of my big wish list items is to have gutters on my shop that feed rainwater into a tank that I can use for my in-greenhouse watering needs. I had the idea to install an underground cistern underneath the greenhouse, and use a pump to get water pressure for pulling the water out of the tank when I use it.

I hardly know where to begin with all this, but I'd love any ideas that any of you all might have!

Wow, 24'x9', what a great size. When I was shopping around for my greenhouse I actually saw some with gutters but they were pretty tiny. We wanted to do the same thing but settled on just running a hose from the collector barrel into the GH. Not great.

A cistern would be great. We had a cistern when I was growing up for laundry because we had sulpher water and it turned the clothes gray. When I lived in town I wanted a cistern for our garden but we never did get around to building it. I think you would be very happy with one.

Would be great if you could also use radiant heat floor from solar. I'm not sure if they even do that, but I know radiant heat is the most efficient.

Are you looking for solarium quality or more of a salvaged parts green house? Solariums you can buy as kits, and once you pick your kit you can then start pouring a footing to hold it. If you salvage sliding doors and windows I would wait until you have enough to complete the rough size you want before pouring the footing to hold it all up.

Thanks for the idea on the radiant heat, Arlene. I have some ideas on heat retention that involve tanks of water on the north wall. I'm going to be doing aquaponics in this greenhouse, too, and all that water will provide some good warmth retention.

Tom, I'm thinking more of a solarium approach. I wouldn't mind using salvagable material but I want the greenhouse to look good because it's front and center. Check out the photo of the site below:



The greenhouse will be directly in front of that red building there, where all the cannas and tapioca plants are. As you can see, our driveway goes right in front of it so it'll be one of the first things you see when you pull in. So I'm willing to buy everything to make sure that it's uniform.

Here's another picture of the site:



My plan is to move out all the cannas, tapiocas and other tropical plants and put that greenhouse right against the shop.

That is a great spot for it. Will it be a heated GH?

Stephanie has a great set up with her shade cloth INSIDE.

I saw that interior shade cloth and I loved the idea! I'll probably do something very similar to that.

Heated: yes, but I'm not yet sure whether I'll use propane or electric.

When will you start or are you still in the planning stage?

Very much still in the planning stage here. I posted this thread to actually start getting my thoughts together!

I really have no real starting point and am feeling a little overwhelmed at the whole thing. But I want it in before this fall and that means I can't wait til the last minute.

If you want it for fall then it is good to start planning now because it's going to take some time and summer will be here before you know it and it always goes by FAST!!

I know there are people with a lot more experience than I have but mine is mainly for starting seedlings and over wintering plants. Mine is generous in size (never big enough) and I love having doors at both ends as well as being Dutch doors. That might be something you may want to consider.

I also have a planting bed on the west side about 30" x8' so I can get an early start on things like cukes, beans, melon.

We're also wanting this mainly for overwintering stuff and seed starting. This past year we had so many trays of seedlings that we didn't have room in the house under the grow lights. That was a real wake up call for me!

I'm planning one interior door that goes into my shop, and at least one exterior door so I can enter the greenhouse from the outside. I may indeed have 2 exterior doors like you're doing. The dutch doors sound like a great idea. We have those at our barn and I love being able to keep just the top half open for airflow.

Yep, that was my problem too, kept adding shelves and lights and my house is tiny!

I love the Dutch doors! We especially just keep the top open if we are away so we don't get visitors

A solarium will look GREAT there Dave. The most important thing when building/ putting it together, is to make sure the footing is VERY level. if it isn't you'll have to shim up the bottom PT(pressure treated) plate; or else the glass will NOT go together smoothly. All you need is a transit to make sure everything is level, if you have to, find a friend who has one or rent one. Trust me here, the more level it is, the easier life will be on you putting it together .
Now the solarium will be a little overwhelming at first when you look at the instructions but once you put up a few sections it gets ALOT easier!
Just find some friends with some patience and it will go pretty good. it'll take probably a week for a newbie to put it together.
Make sure to get a solarium with opening awnings for some of the glass panes in the roof, and the fan kit that can go in the "gable" end of the solarium.
I would Dig out some of the earth inside of the solarium and add sand and crushed rock on top of that to keep moisture and mold at bay

Good advice, Tom.

What do you think of a concrete floor, sloped with a drain in the center?

Dave,

Love the cistern idea. Back in the 50's in west Texas, my grandfather put in a cistern for their drinking water from gutters on their house. As far as I know they never ran out of water even through all the droughts.

My lean to on the south side of my house is 16 x 7 1/2 so I am jealous. I have had mine for a little over a year and quickly ran out of space.

I think there will be pros and cons on the concrete floor. I would imagine after a time you would have a challenge with your drain stopping up.

Duane

Plus concrete is hard on the legs/feet if standing in there for long periods. Maybe brick?

Thanks Duane and Arlene, sounds like concrete is a "no go" and that's perfectly fine with me because it's also the most expensive option!

I like the idea of using gravel covered with black fabric.

yah, concrete is hard on your feet....... the plus side of it during the winter it could be a "solar" heat sink for the green house, especially if your were to paint it a dark color. I like the crushed stone because you can easily rinse it down with a hose if need be.

The crushed stone is sounding attractive to me. I'm leaning that way.

Dave, I have two greenhouses. One is dedicated to orchids and seedlings and the other "everything else tropicals". Because I wanted high humidity in both GH's, I decided to put a 4" layer of cypress mulch as the base (over clay soil) and then covered this with black floor fabric. I not only got my high humidity (just spray the fabric with water) but as a bonus I got great drainage and an easy-on-the-feet-and-legs surface. This is an inexpensive alternative and is easy to put down. Ken in Mississippi