[RobertSWMissouri]

If this is of interest (I just had one person ask), I will slowly post the pictures of our greenhouse build, and add in lessons already learned, and more as we go along and learn to use this 4-season, no back up heat semi-tropical greenhouse, using an "earth bank" to provided needed winter heat AND summer cooling.

Outline: Retaining wall, ground source, greenhouse, first lessons learned.

2020: I got a bid for the short concrete retaining wall needed to the South in order to build the level pad for the greenhouse, it was almost as much as for all the concrete walls in the greenhouse ! Almost all the cost was labor or opportunity costs. I had some left over concrete form I build over 20 years ago in the barn.... so build this short retaining wall with the buttresses projecting out to the South to build micro-climates (we are 1 zone too far North for pomegranates and to possibly overwinter figs w/o protection for a breba crop; the Roman's build 'greenhouses' w/o any glass in Europe to be able to grow their favorite Mediterranean foods up to Northern France. South facing wall, dirt berm to the North, gave a 1 climate zone protected area 1.5x height of wall to the South..... The retaining wall starts 2' high, and ends up to the West 5' tall.

 

[RobertSWMissouri]

one more of the retaining wall.

 

[the labyrinth]

Please keep posting your progress

 

[RobertSWMissouri]

Will see if I can get my 'drawings' posted.... for an overview.

 

[RobertSWMissouri]

Late 2020: Get all the underground work done so it can settle over winter, to start actual construction in the spring:

Concept (lot's of u-tube video's out there from citrus in the snow (open loop) to the closed loops called Earthbank, Climate Battery, Ground to Air Heat Transfer (GAHT), etc.), greenhouses get TOO HOT! Dig a 5' deep hole under the greenhouse, line it with 2" of foam.

Take that hot air from the peak of the roof, and blow it down the large pipe to a manifold running North-South at the East end of the hole, at the 5' level, and connect 4" perforated and corregated HDPE sock covered drain pipes running every 18-20"" from this manifold to another manifold at the West end, then a riser pipe to blow the now warmed air (in the winter) or now cooled air ( in the summer) back up into the greenhouse. Fill in the hole half way with the dirt taken out, and repeat entire system at the 2.5' down level.

Hitch #1: Plastic prices! The initial plan was for a 12" PVC down to the ground to the 12" PVC manifold... if you did not notice, PVC prices went through the roof (example, the 2" PVC conduit to run the underground electric service to the pad COST MORE THAN THE UNDERGROUND TRIPLEX WIRE!!!). While 12" HDPE corrugated DOUBLE WALL (so it was smooth on the inside to decrease air turbulence) was far cheaper... and actually worked out WELL. (You want the 4" pipe corrugated to create air turbulence to increase heat transfer).

 

[RobertSWMissouri]

start, then down low to

 

[RobertSWMissouri]

Sorry for the duplicated pictures, I guess I will post single pictures in the future, as this was the 5th attempt to attach these 3.... and only these 3

 

[Kas1321]

I live in North Central Arkansas and I am doing something very similar. The south side of my shop is a 50' block wall and I am going to use that as the north side of my green house. Hopefully the concrete block will act as a heat sink and keep the greenhouse warmer in the winter.

 

[RobertSWMissouri]

I live in North Central Arkansas and I am doing something very similar. The south side of my shop is a 50' block wall and I am going to use that as the north side of my green house. Hopefully the concrete block will act as a heat sink and keep the greenhouse warmer in the winter.

Hopefully you can insulate the INSIDE of the block wall ?

 

[RobertSWMissouri]

Finishing up fall 2020, pad ready for spring...

 

[RobertSWMissouri]

2021... Concrete work, the 'plan' was to sub the concrete work out.... the contractor we were going to use, signed an exclusive concrete work only contract with a large contractor for a retainer "more money than we have every made before...", the large companies are 2+ years out, we talked to every smaller concrete person who does walls (many have quit in this area "we can make more money doing flat work") and found no one who would even give us a bid! Foundation form board stored in the barn loft, form enough for all the short walls there too... and just as we were at the drop dead timeline, the price of 3/4" plywood dropped from $100 a sheet to $30... so site built forms and family labor... (and 3/4" sheathing on the North roof...).

We are far enough from New Madrid fault line that we 'should' not need to worry... no local known fault lines close... so we built to exceed earthquake standards anyway... including a foundation well tied together including a 'beam' at midpoint - bridging the fill / tie the long legs of the foundation together / support the buttress for the North wall. Foundations for retaining walls to the East and West integral too...

 

[RobertSWMissouri]

Foundations for the South side raised beds (of poured concrete) fully tied into the main foundations too.....

Then site built forms for the walls.

 

[Geisteskrank Einzeller]

Really appreciate this. And Earthbank, Climate Battery, Ground to Air Heat Transfer (GAHT). Is any hand back filling required prior to back filling with the loader? To prevent the socked drain pipes from being crushed?

 

[RobertSWMissouri]

No, no hand filling required... the skid steer works forward so there is always dirt over the drain pipes. I think the minimum is a foot, in this case it was over 2' so no worries at all. Driving on over and over and over again compacts the fill down well too... I was expecting at least 6-8" of settling over the winter, got 1 to 2" !!!!

Poured all the greenhouse walls and the South planting bed at one time, no problems with the 8" walls, but one section of the 2" tall wall lifted (using 2x8 vertical form sideways.. with only one row of snap-ties at the 1' 'center' level they rotated with the bottom out and the top IN. Had to hand clean out about a couple wheel barrow loads of wet concrete to re-set the forms. Filled this section back in when we poured the East and West retaining walls - using the same plywood and 2x4 bracing a second time to decrease cost (and both pours were well over the minimum amount required for concrete delivery)

 

[RobertSWMissouri]

stripping forms from first pour (note the gap), getting ready for the retaining walls:

 

[RobertSWMissouri]

Still stripping forms from second pour, already putting up scaffolding (put up 3, 2-level towers with walk boards (the foundation form boards re-used again) between them).

 

[Bluesky9]

You will have to raise a lot of "carrots" to pay for this greenhouse. We have just poured the piers for a greenhouse in the backyard.

 

[RobertSWMissouri]

Think of the value of:

A "Caribbean vacation" out in the (semi) tropical rain forest.... a 20 foot walk from the house... every time the sun is out for 2 hours all winter long......

A well organized working space (so the job actually gets done), with shelves for plant starting etc.

A really nice place to work (there will be a long workbench along the North wall of the East half... about 18') in the winter....

Citrus, papaya, avocado, banana etc... and tomatoes all winter long ????

Oops #1: we have already found out that even in winter too warm for spinach and lettuce (although we should be able to plant and harvest as mini-greens, not good use of space as we can grow spinach and lettuce outside under just cold frames.. (and another hoop house is in the planning stage).

Have not tired carrots yet. lol

 

[RobertSWMissouri]

Post and Beam framing; oak if fairly rot resistant (local sawmill), it is on treated plates, but most importantly it matches the construction of the house and is what the wife wanted ! This type of greenhouse is supposed to have some problems with LOW humidity (and so far, NO 'rain' from the inside of the polycarbonate South roof).

 

[Bluesky9]

Nice!