A recent update from the person who received the yucca is that it is green and doing well. The transplanted cholla are doing well, of course, but it will be a while before I know if any sacaton survived. We have been making progress but not as quickly as we hoped. (No surprise there! ;-) ) We have the foundation blocks for the outside beds in place up to ground level and filled with dirt. Pavers have been placed, but not yet leveled, between the existing shed and the north edge of the foundation. We have the water and electrical stubbed in. We have the SHCS tubes in place for the outside beds of the east greenhouse and hope to start filling that section soon with the removed dirt. We have removed all planned use of poured concrete from our plans and have made this planned structure possible to remove easily while still unlikely to be blown away. (Mostly due to bolting the foundation via J-bolts to rebar under bond beam cement blocks.) DH will be checking to see what type of permits/inspections we will need for electrical, water, and structures. I suspect that it will be just water and electric. We won't fill in any more until we find out. It is getting hot already so we will be putting in the outside structure and shade cloth before the central shed and greenhouses. That way we can work in the shade. :-)

I can give you some help, although it's been so many years since I built mine, some of the small details aren't clear to me anymore. I'm looking at the newest version of the Harbor Freight manual, and the part 81 white plastic bushings are mentioned on page 17, in step number 5. Apparently the bushings were to be inserted over the part 78 Double Brace Bolts (part 78), before you used those bolts to finally attach the side diagonal struts (part 80.) Maybe you can locate the side diagonal struts on your greenhouse (part 80) and look at the bolts holding it in place, to see if it really matters if there's a bushing to space something a bit apart, on the long bolt part 78 bolt. I'm not sure how difficult it would be to back track, at this point, and maybe it's not all that important.

Sheri: The Aluminet stretches in one direction only, so when you order it, make sure you have the fabric cut to stretch in the direction it will hang from top to bottom. When the sales rep from IGC (where I ordered mine) told me the vents would open under the fabric, I was a bit doubious, but she was right. The key is to mount the fabric without stretching it tightly. My husband was concerned that the corners of the vent windows might punch holes in the aluminet fabric and wrapped rags around them. So far, even with the vents opened full and pulling the fabric, no holes, but I'm looking for a more elegant solution. Fat, self adheseive foam bumpers come to mind. But I didn't suggest that you use the aluminet AS a screen, only that when it's draped over the ROOF vents, it serves as one, which I found ironic, because we made screens for the roof vents, that will soon serve as storm panels for winter, as we can use them to hold bubble wrap in place under the vents. For your intake vents, use standard screening material, in a frame. To screen the powered intake vents on my GH, we used white vinyl house trim materials to create a box frame, 5- 1/2" deep, to allow the vents to open out, then just made screens using the screen channels, corners & spline sold in any home center. The box is made of 1 x 6 vinyl trim board, (actually 3/4 X 5- 1/2) so the edge facing out is wide enough to accomodate the screen frame, that is mounted to the box face with screws. To give a surface to mount the box to the GH, we used vinyl brickmould. The box sits inside brickmould, attached with small screws. The brickmould was fitted tightly around and to the fan frame, sealed with silicone. Once we fiddled the design, they were pretty easy to make and give me the ability to both remove the screens for cleaning, and in late fall, when we seal up the GH for winter, we can seal the vents by placing insulation in the boxes, then use the screens to hold it in place. My inspiration was shadowboxes, which, when you look at them, are no more than a picture frame with a second frame inside of it that projects out, with another frame on it's face, to hold the glass. From the craft shop to the GH. LOL!

I built a similar 12x12 greenhouse from 2x4 treated lumber, but I painted after framing before glazing. Don't forget to use a good oil-based primer coat before painting. I have been through 2 years including 60 mph winds, 8" of snow, and 100+ F summer temps satisfactorily. I have some suggestions for you to consider. First, most GH owners would recommend twin-wall polycarbonate glazing. Second, you can stiffen and insulate the greenhouse by covering north wall with 1/2" treated plywood with 2" foam insulation panels. They come in 2'x8' panels which fit nicely if you space your 2x4s properly. You can do the same (with smaller benefit) by enclosing the bottom 2-3' of the side walls (as kneewalls). Little useful sunlight enters here. Third, with these changes, you don't need diagonal braces. Nor do you need cross braces on the rafters if the 12' peak length is not exceeded. I recommend using galvanized nail-on straps (not sure what they're called) at the peak and other ends of the rafters to hold the joints together. With primer and 2 coats of exterior paint, these have held up well so far. Now for condensation, venting, etc.... you will need good internal circulation fans to reduce mold/fungus problems. I think you will want the roof-glazing to overhang the sides by ~1' to keep rain out. Also, I think you will want to attach the glazing panels to the exterior of the studs/rafters and cover the joints with aluminum T-bars. Then, seal the seams with silicone. I suggest you look at the construction details at http://www.cloudtops.com/polycarbonate_verolite.htm. You will also have to provide some means of maintaining high enough humidity when you heat in winter: misters, foggers, etc. If you plan to keep any plants in the GH during summer, you will need shadecloth, misters/foggers for cooling, and larger exhaust fan. Other thoughts on your specific questions: By windows I think you mean roof vents. This will be needed for summer use. See how on-line GH vendors do it, especially the automatic open/close devices. I built mine from 1x2s but I have trouble sealing from rain. The glass/aluminum door is fine. Check your local building code or hire a licensed electrician to do the electricity business safely/legally. I will gladly answer questions and will welcome comments by others correcting or improving upon my comments.