DAY 1

Pretty neat.

Tagtastic


I want to do this too. Post more pics and write ups if you could.

Looking forward to seeing this project completed.

Me too!
Once upon a time I was a carpenter.  I can say with some authority that 30 years makes a big difference in how quickly you get things done and how sore you are afterwards.

Weather's kinda crappy here now so we haven't gotten much done in the last couple days, but the weekend's supposed to be nice so hoping to make more progress then.

Tagged to see it grow.

TRG

I hope you have some good weather soon midmo because I would love to see an update

Work and bad weather have gotten in the way, but the plan is to hit it hard this weekend.
Built a "stripper" this morning to convert some rolls of foam sill insulation into 1.5" strips, which will be used as gaskets/padding for all of the twinwall sheets that will make up the walls:



Details, details...

I like the pics of a well built stripper.

TRG

Double tap

I may or may not be stealing that idea for future use.

 

Lots done today, but not much photo-worthy.  Lots of trips between the greenhouse and the workshop, up and down ladders... midmo tired

Built some braces across the 12' span.  I'm a little concerned about wind loading on the long walls, with no real lateral bracing to speak of.  24' is a long way to go with no roof structure to add some strength. Might end up sinking a post outside and doing some kind of flying buttress arrangment off the back side (East).  We'll see.



Whipped up some little doodads to receive the ends of the cattle panels that will serve as roof framing.  48' of this stuff cut out of 2-by's (they're 1x1 now) is a lot of fabricatin':  And yes, Mrs. Midmo's already noted that they need paint.  Guess what Mrs. Midmo gets to do tomorrow morning...  



Did a lot of "invisible" stuff... shimming up the foundation here and there, bolting things down proper (just had deck screws in there before), squaring and plumbing.

Callin' it quits for the day.  First thing in the morning is taking a side grinder to the cattle panels to cut them to the right length, then popping 'em in.  Also need to fabricate some arches for the ends; planning on doing that by laminating three layers of 1/2" plywood together to form the same curve the cattle panels want to take.  Might be interesting.

We'd like to get the twinwall installed tomorrow just to help rain-proof the whole thing (probably just throw a tarp over the roof for now until I get ready to put on the plastic).  Dunno, it'll be a race.  Rain forecast all week.



Beer-thirty!

Thanks for the progress report Everything is looking great and yes, Mrs. Midmo needs to get busy with a brush

I do 99% of the things around here by myself and I can definitely understand working your butt off all day and then stepping back at the end of the day and wondering what the heck was done.

Back when I used to work construction we used to say that two people can do the work of three. Now that I'm almost 50 I can safely say that I do the work of one old fart

With regards to the wind shear ... If this were mine I would notch the walls to accept a 2x4 cross brace so it's flush to the oputside. An inverted "v" with top ends if the bracing stopping at the top plate and the lower ends stopping at the corners. This wind brace as we used to call them increases wind loads dramatically.

Yep, in fact you can see in the pics where I've got temporary lateral braces run more or less the same way on the long walls.  That will come out once I get the sheathing and poly installed, since 4x8 sheets of pretty much anything screwed down on 16" centers will provide the same kind of lateral bracing.  The real problem is in the center of the structure; those long walls want something tying the top of one to the bottom of the other to keep them from flexing from side to side.  Hard to make it out, but in the first pic I have 2-by's run in an X that way (leftmost unpainted boards).  Unfortunately that's a no-go in the finished structure; having to traverse that X in the middle would be a pain when watering or otherwise messing with the plants.  I'll figure out something, though.  

More progress today... cattle panels cut and installed, twinwall installed down one wall and part of another.  Wish weekends were three days long.  

Getting there though!

Is this a kit?  Looks like a great project.  Looks awesome!

What's the roof going to be?

Cool project so far - thanks for posting!

Nice. Can't wait to see it done and how you set it up inside.

Why did you decide to go with cattle panels for the roof instead of PVC pipe, or some other means to make an arch?

Just curious what your thought process was.

Nope, not a kit.  Just wingin' it.


Roof will be a double layer of regular greenhouse 6 mil poly film, eventually with a blower to inflate space between the layers for insulation.  The inflation part may have to wait until later in the summer, though - don't have power to run down there yet to run the blower.  I've got a little 60-watt solar setup with a couple of deep-cycle batteries that I may experiment with, but eventually I want to dig a trench down there anyway, for electric, water, and some Cat 5 cable so I can put a computer out there (environmental monitoring, etc.).


The foundation the greenhouse is sitting on was originally put there for a PVC hoop-house greenhouse - our first effort.  That failed miserably; joints broke regularly, and when we did get the frame to stay together long enough to consider putting plastic over it, it was still pretty flimsy/wobbly (using 1" PVC).  I know it can be done... there are a lot of PVC hoop houses out there.  But overall it just turned me off from using PVC, and I figured it wouldn't cost a whole lot more to just stick-frame with big-box store lumber.

I did consider framing a roof and using clear corrugated roofing or something on it, but that would have put the lumber bill a lot higher.  I also liked the insulation value of the poly "bubble", and the cattle panels just seemed like a logical choice for the support... they're flexible enough to make the curve easily, readily available in this area, relatively cheap, and if for some reason it doesn't work out - holes in the poly from chafing against the panels or something - I've got plenty of uses for cattle panels around here if I end up ripping it off and trying something different.

Thanks to all for the interest! I wish we'd gotten further along this weekend; I really wanted to get the rest of the twinwall up and a tarp or something temporarily thrown over the whole mess before rain sets in again this week, but I'm not as young as I used to be.  The old Advil bottle's been my friend the last few days.

very cool! I would love to do this one day on my place. What County are you in?

Mid-Missouri
That's not meant to be nearly as smart-assed as it sounds.  I just have real reservations about internet privacy, and that's about as far as I'm willing to narrow it down.  Hell, you never know when I'm gonna piss off the wrong person here, and some a'these guys have guns!  I've seen a few posts on Arfcom that lead me to believe that some of the members are, umm, a bit "tightly wound".

So nothing personal, and thanks for the compliment!

Honestly, I always thought your username meant you were halfway to being this guy...



Looks good on the greenhouse.  Interesting roofing choice.

I planned to make a similar arch, fromteh same materials, for a chicken run.

TRG

Little progress Monday, had to work, and it was too windy here to even think about trying to install more twinwall or anything.  Did stop at the hardware store on the way home and picked up some 10' pieces of 3/4" EMT conduit.  Smooshed, bent and drilled the ends, and rattle-can painted 'em.  I'm going to install these as an inverted V brace from the center of the 2x6 cross-braces I put in in at 8' and 16', running down to the bottom wall plate, to stiffen up the long walls.





Hope to install them this afternoon after work, then probably work on tarping up everything I can before rain and thunderstorms set in for the next couple of days.

Ha! No biggie, totally understand. Just curious as we might be neighbors. Though I'm about 7000 miles away currently. Planning on revamping my property a bit when I get back though. Greenhouse in the future, but probably going to be a bit.

Closing in on 4" of rain here in the last two days

We need the rain, but I sure wish it had held off another week.  Hate having all that framing exposed during this much rain, but at least it's all painted with an exterior paint.  That was mainly because I knew the inside of the greenhouse would be very humid most of the time, though... not to prevent against this kind of deluge.  Could've used another coat, too.

Not much progress, of course.  I did get the V-braces installed; wanted to get them in because of the high wind threat accompanying the thunderstorms.  They helped stiffen things up a LOT.

What's your source and rough pricing on the twinwall?

FarmTek, I got 8mm sheets, which look like they're running $68.49/sheet now. Shipping was about a hundred bucks; there's a special packaging charge since they are big and relatively delicate, and they have to be truck-shipped.

I searched (...and searched, and searched..) around here but couldn't find any source locally.  It's pretty nice stuff, though.  Easy to work with, and looks great when installed.

Arghhhh...



I'm gonna get hammered again.

Ouch.
I've got rain coming my way tomorrow.

That kept me from going to Jefferson City for the 2nd Amendment Rights Rally yesterday.  But they held it at an odd time of the month this year and the turnout was pretty lame as a result. Didn't miss much.

Did have 3-4 tornadoes spotted in the area though. That was some good entertainment for a while.

"Say midmo, looks like you're gonna have to build some kind of an arch to cover the ends of the cattle panels to keep the pointy ends from ripping the plastic to shreds.  Bet that'll be a pain in the butt, eh?"

Why yes, yes indeed.

The original plan was just to form an arch out of three layers of 1/2" plywood, bent into the correct curve and laminated together with glue and screws.  Surely a 3.5" wide strip of half-inch ply is flexible enough to make that gentle curve, right?  WRONG!  First attempt broke doing the very first strip.  "OK" sez I... "this plywood has been sitting in garage for about two years, and probably has roughly the same moisture content as the Gobi desert. Water, that's what it needs!"

So I pitched 'em all in the pool.

I let them soak for an hour, and tried again.  SNAP!  Barely made it any further around the curve than the first time.

So, I ripped a few more strips, and left the whole pile out on the deck to enjoy two days of epic rain - a hair over 6" by the time it was done. Yesterday I tried again...  SNAP!



Obviously the 1/2" ply wasn't going to work.  The last piece, hurled to Earth in shame and frustration:



Regroup.

The new plan, initiated yesterday, was to instead go with 1/8" strips of Masonite.  Not an ideal solution for a high-humidity situation, but my choices around here are limited.  I'll just paint the hell out of it and and hope for the best.

I still wanted a full 1.5" thickness, so that would mean 12 layers of the stuff.  The arc of the curve is between 13 and 14 feet, so it'll take more than one 8' long strip for each layer.  I want a 1" deep by 1/2" wide gap in the middle to receive the ends of cattle panels, so I need (16) 3.5" and (8) 2.5"... 24 of these suckers per arch, X 2 arches.  And Lord, how I love ripping Masonite.

The concept looks like this:



On the bright side, I think it's gonna work.  The glue-up was a booger:







Note the abandoned flip-flop in the last image... that's how fast my daughter, who was spraying the strips with water to activate the Gorilla Glue, left the scene when I started talking about doing the second arch.  

I did get the first arch done except for sanding, bracing and painting, and this morning took it out to the greenhouse, stuck it up on the end, and - miracle of miracles - IT FIT THE CURVE EXACTLY!  

I've got the second one in the gluing jig now.  I hope by the end of the day today to have both cleaned up, sanded, a couple of 2-by's for bracing installed, and painted.  Probably won't get them up today because I'm home alone and they're a little heavier than I want to juggle on a ladder by myself, but it's still progress.

Only other progress recently was installing the conduit lateral braces inside, to address my concerns about wind loading on the long wall. They work like a champ. Probably end up running a couple more from the same bolts up to the cattle panels to firm things up there a bit, too.



Back to work!  I've dawdled here long enough...

Nice, but very labor intensive design.

I learned a loooong time ago, never use untreated wood for any construction.  Paint is just paint, and wood loves, loves, loves to soak up moisture, from any source, and rot.

Pressure treated, or go home.  Even if the wood does not 'come in to ground contact' ... I still use pressure treated wood.

TRG

I'd agree with you on the end arches, and if I were about to do it again I'd probably do something different... straight trusses or something.  It wouldn't have been so bad had the original idea to use a layer of half-inch strips of plywood had worked out, but in the end I just decided to invest a little more time instead of more money.

For the rest of it, it's not really that labor intensive at all.  The 'Day 1' pic at the top really is day one - although we actually cut and painted all the studs the day before, erecting the frame really did take less than one day.  Sure, there are other options - aluminum frames, bent conduit, etc., but those are either expensive or, in my opinion anyway, inferior construction methods.  The wood frame also makes it easy to build shelving, hang baskets, etc. inside.  There are pluses and minuses to every solution, of course, but in the end I just decided to go with what was readily available, easy to work with, and relatively inexpensive.

I'd be interested to hear what you'd do differently, though.  I'm not one of those guys who always insists that "my way is the right way" 100% of the time, and I've found I learn a lot more by listening than I do by trying to convince others of how clever I am.

Oh, I certainly gave treated lumber strong consideration.  It would definitely have been superior to plain framing lumber, and the extra cost would have pretty much come out as a wash when compared to the studs + paint.  The big problem with it, at least around here, is that pressure-treated wood warps like a sumbitch.  It comes from the lumberyard literally dripping preservative, and as it dries, particularly if in the sun, it goes all Salvador Dali on you.  Warped and twisted studs would have presented a real problem for hanging that twinwall, since tolerances are pretty tight and you can't really cheat things around to make them fit.

It was hard enough finding enough straight untreated 2-by's. The quality of construction lumber these days is pretty sad; if I'd have bought a banded bundle of 2-by's for the project, I fully expect I would have had to figure in at least a 50% waste factor for rejects,

I'm not too worried about the paint, though.  A good coat of decent exterior paint has kept many a wooden building around here standing for a hundred-plus years.  But we'll see.  If I have to collect up those elusive straight treated 2-by's over the next few years and replace studs one by one, so be it. The top and bottom plates are all pressure-treated, though.

I was curious why you decided to use cattle panels. I've seen some older houses use panels, but most of the new stuff is just 1.5" galvanized tube rolled into an arch on 4 - 6 ft centers. You can roll your own arches, that's what we do now.





Double layer inflated poly works great. Watch your snow load. If you keep them warm, it will melt off. If you run them cold, 14" of snow will collapse them. I know of several commercial operations that lost dozens of greenhouses due to the build up of just a couple of inches of ice that they didn't melt off.



I took some pics of some greenhouses down the road with a slightly different design that you might find interesting. I'll upload it tomorrow. All mine are a hodge pod of old and new construction and making what you have work for as cheap as possible.

I was able to upload them straight from my phone. These arent my greenhouses, but they are some of the nicest "cheap" commercial greenhouses Ive seen. They used a custom truss on the sidewall then bolted the bows straight to the truss. No wood at all. But since you've already got wooden framing, this would work.

Not sure if you answered this yet, but what are your plans for the floor? Will you be adding barrels for rainwater storage / thermal mass?

I ask because I am gathering ideas. Your build looks really nice so far!

I thought about tubing, but I didn't have the equipment to bend it properly (and consistently).  If the cattle panels don't work out, for example if it's too much wear and tear on the plastic, then I'd probably consider redoing it with tubing.  Can I ask how you bend yours?  A jig, or ??

Right now it's a dirt floor, the plan is to lay down some water-permeable landscaping/weed block fabric, and put a couple of inches of gravel over that.  We wanted it to be able to drain easily so we don't have to worry about overspray from water hoses, etc.  A slab would have been nice, but that would be WAY over our budget.

Endwall arches are done!

For what you're doing, use chain link fence rail. You can get some heavier walled stuff, but for the size you're using, if you build it right, you can do chin-ups on it, no matter what you weigh.

Here's our super high tech bender:





The two bottom wheels adjust in and out on a 1/2" bolt. You run the tube through there the first time with a very slight curve, then adjust it in on each pass until you get the bow that you want. You may have to run it through there 5 or 6 times or as few as three, just keep the pipe level when you roll it through there. If you adjust it too much in one pass, you will crimp it.

We had a simpler rig at one time with smaller rollers that were mounted on a beam, and we adjusted the beam in and out with a pair of vice grips. There was no crank, you just pushed the pipe through. Kinda hard to describe, it was crude, but it worked ok. I've been thinking about building another one using cast iron gate wheels.



Like I said, we get creative on building stuff cheap. It's all about cost per sq ft commercially. I have people come and tell me they need a $200k greenhouse that runs automatically. There is no such thing. It's like saying you're going to build a completely automatic nursing home for old people. It just doesn't work that way.

But if you build a $200k greenhouse, just what are you going to grow to pay for it?

Well now there you go.  I don't have one'a them fancy doodads.

But I hear ya. I'd really like to get tooled up to be able to do this, because honestly I doubt it's going to stop at this one greenhouse.  My wife does this professionally, and I foresee some hoop houses in the future.  We don't even have the greenhouse covered up yet, and there's already talk about needing a lath/shade house too.  This one's at least partially an experiment; some place to learn things like "next time use tubing.." ;)

I'd also like to be able to crank out hoops for row covers.  We've got a big garden, and the weather seems to get a little crazier every year.  Greenhouses, hoop houses, row covers, frost blankets... all that stuff is leverage against the variability of weather.

But I don't really regret the direction we took.  For now, this one's a hobby, so the commercial economics don't really come into play.  I'll build one pretty one, then the rest can look like a commercial operation if need be.

Just trying to give you some ideas.

I meet a lot of folks who want to get into it and are lost in the weeds. Worse yet are the folks who've sunk $100k into it, quit their day jobs and don't know what they are doing. It's like the restaurant business. Keep an eye out for used stuff, we've found lots of deals out there on commercial equipment just because we knew what we were looking for.

Well there you go.

I can't believe the prices they're trying to charge online for the hoops. I may need to bend a bunch and sell the bows and the plastic to local folks next Spring.

(not a for sale ad)

Ayup, thanks Corporal!

I'd actually looked at that "hoopbenders" site somewhere along the line, but by then I'd already pretty much bought into the stick-framing/cattle panel idea.  It's still really not that bad an option, except for the endwall arches.  I forgot to mention earlier that I also like the vertical walls... nice to be able to put in benches right up to the walls.  I know you can do that with tube framing too... some of the pictures you included showed that.  But then you're bumping up the complexity level a bit and getting away from some of the simplicity of a Quonset-type design.  It starts getting close to a "six a' one, half dozen of the other" thing.  But again, I know tube arches have their place.  There's a buttload of tube greenhouses out there, so I know they work.  I'm just not going to beat myself up over the wood framing.  There's a fair number of those out there too.

+1 on the "Jomamma's Hoop Greenhouse Kits"!  If I'd have been able to run to Lowe's and pick up a bunch of bows inexpensively, I almost certainly would have went that route.

The plastic electrical conduit from lowes works perfect for row cover hoops. Around $1.50 per hoop. You can either drill holes and use wire to make it stay bowed, or hammer some rebar in the ground and slip the ends on. At some point I may try a heat gun and see if I can make them keep the curve that way. Hooping them over a 4' wide bed gives you a hoop about 2.5'-3' tall.