Introduction: Greenhouse Improvement
We started with the small 6X8 greenhouse from Harbor Freight and added some much needed height and raised bed grow boxes on the interior. Custom Cedar door with wooden latch replaced the small aluminum slider that came with the greenhouse.
Step 1: Developing the Site
We cleared a tree from the area where we wanted to place the greenhouse, wish I had some pics of these early steps so will try to describe in some details what we may not have pictures for. The one I do have is probably the earliest and shows a bit of what I will describe. After removing the tree and what little grass was in the area we laid down fabric that we purchased at Sams club. The total area we covered is approximately 18x 14 and will show some pictures of the surrounding area. After the fabric is down we brought in a few yards of what is called 5/8 minus gravel to not only cover the area but use to build up the are that because the perimeter of the 6x8 footprint. We built this area up an additional 4 inches or so to support the base of our foundation this you can see in this picture are 4x6. In the far corner you can just make out one of the metal brackets holding each corner together. After they were all in place and brackets bolted on with galvanized screws (1/2 x 3) we drilled two 1/2 holes in each 4x6 and dropped 24 inch pieces of rebar to really secure it to the site.
Step 2: Building Pony Wall
Similar picture to the last but shows short wall we built to give us some sort of height inside the greenhouse. This step alone is what really starts to make this a significant upgrade. The wall we built including top and bottom plates was 14 inches in height. Putting this on top of the 4x6 and given that the rock base under that was raised 4 inches we have the top plate of the wall about 20 inches above the ground level.
Step 3: Sheathing the Outside of the Pony Wall
I will attempt to describe what I do not have in pictures but some you can still see. The outside of the pony walls were sheathed in some cedar I picked up at an auction that was actually milled for the purpose of grilling salmon. It is 5/16 thick by 5 inches wide and I had a ton of it so figured why not wrap the walls with it and as you will see have other uses as well. Air nailer made fast work of this. After this step was when I started to place the already assembled frame on the base. It was attached with galvanized crews with large washers every 6 inches, far more that what is recommended. I was pleasantly surprised at the strength the frame achieved at this point.
Step 4: Sheathing Inside of Pony Wall
On the inside of the wall I wanted something solid and what I had laying around was some 3/8 ply so that is what was used to cover the inside of the pony wall. Since we wanted grow boxes inside and I did not want the dirt against the plywood we covered it with some large black garbage bags that have been in the shop forever so I was very happy to use some of them. I generally overlapped the seams and stapled them to the plywood and up and over the edges of the wall.
Step 5: Building Boxes Inside
This photo shows more detail of the boxes we made. We divided the interior space using 2x12 front to back and across the short area in the back giving us three separate areas. All areas exposed to the dirt had the black plastic treatment and the interior used up for of the cedar, guess we won't be grilling any Salmon anytime soon! I think you can also see how we used more of the cedar to top off all the inside edges, I believe the pieces are 2 1/2 to 3 inches in width. Also in this picture I realize that the door opening has been cut, didn't want to step up and over that wall so a custom door will need to be built and framing put in place to support it.
Step 6: Panels Going On
I wanted to thank all the people who have posted videos on how to assemble the greenhouse, I found them very valuable. i assembled the whole frame before building the pony wall so I would have exact dimensions from which to build it and it worked out perfectly. In this shot panels are going on and we are about to get it enclosed.
Step 7: Building the Door Frame
To mount the door we need to build a wooden frame that we can attach the hinges to. The way I attached the wood to the Aluminum frame was to make a sandwich and put wood on both sides to give my wood screws something more to grab onto and to create a more substantial feeling frame. This step also added to the rigidity of the whole structure, I am continually amazed at how solid this is after having first assembled it separately from the base saw how floppy it was in that state. I really had my doubts about the strength of the structure until fastening it down and adding these wood pieces. I decided to leave the old sliding frame in place because in addition to just not wanting to cut it off I thought if I ever added a small solar panel it just might come in handy as an attachment point.
Step 8: Dirt and Initial Planting
Before working on the door we wanted to get some plants in so we hauled several yards of good quality soil and got the boxes filled, should have counted the wheelbarrow loads it was a lot. The depth of the boxes really because apparent as we started to fill them up. This picture is a few weeks old as these were started as seeds.
Step 9: Building the Door
Dood was constructed using 5/4 cedar in 4 and 6 inch widths. I laid out the door so I could utilize the greenhouse panels that were supposed to go in the original aluminum door frame. Since this door is taller than the one that came with the kit I needed to go back to my grilling cedar one more time to fill in the bottom panel. Joints were made with biscuit cutter and waterproof titebond glue. Plastic cut easily with table saw to fit into the frames and more Cedar used to frame the panels and keep them in place. Hinges were some heavy duty brass door hinges I have had laying around for 20 years, really overkill for this lightweight door but already paid for. This project is really clearing out the shop!
Step 10: Wooden Door Latch
Last step was to figure out a way to keep the door closed and I had just enough 5/4 cedar left over to get this done. I used the table saw to notch the main piece the pivot piece goes thru. Used bandsaw to shape, router table to round over and sanded. I already had the finish on the door at this point and kind of wish I didn't so I could have glued it on. At some point I think I will put the same finish on the cedar around the base of the greenhouse as I did on the door.