Jimmy,

I can't comment on the sturdiness of the 10x12 but our 6x8 HFG has withstood several windstorms without losing any panels. Todays storm felled a 100 foot pine which missed the greenhouse by 12 feet :-)
We use the clips from Charlies.

SH

If you buy the 10x12 you will need to modify the framework before it will withstand 70 plus wind.
I posted pictures of the modifications that I did to mine.
You can find them in the post 10x12 HFGH modifications.

Ok Gadenerwantabe, (I have a hard time with that name, since you seem to know quite a bit more about this than most of us).

Anyhow, correct me if I am wrong.
It seems that your primary modifications were to attach the 10x12 to a wood base (3 L brackets per side), and then the Corner reinforcements. As well as replacing the lightweight bolts with Stainless Steel Bolts?

Did you upgrade the Spring clips for the panels with the ones from Charlies, or are they the clips that came with the Kit.

I noticed that you did not tape the edges of the panels, nor did you put weather-stripping on the edges. If you have also built the 6x8, do you think that the panels are more secure with the 10x12?

I did not see any mention of your having made any reinforcement of the upper portions of the structure.

I see from your pictures that the diagonals only cross one panel section each, and there are no diagonals in the roof section. Do you get much Frame flex on the panels in between the diagonal reinforced panels, or in the roof panels?

My biggest concern is with frame flex, with the second biggest concern being with the whole structure blowing away (this should be handled with ground anchors). We only get hurricane force winds here about once a year, but the steady blowing of the 35 MPH winds might cause flexing that might cause panels to pop out.

Do you think it would benefit from additional diagonals, or perhaps some corner to corner cables?

To be honest I would feel much more comfortable it the roof were not so pointy, but that would not be a feasible modification.

Pretty sad, the 6x8 is too small, and I think the 10x12 is too big LOL

From your other posts, and your pictures, it does not appear that I could sink it more than about 6 inches.

And one other question if you do not mind, do you think it would be better to have one of the sides to the wind, or face on, with the doors facing the wind?

Trust me....It's NEVER too big! I have 2 of the 6x8's built end to end and I WANT this 10x12...2 of them in fact. I'd like to modify them as a long lean-to aloong the south side of my house. Then use the 2 6x8's for seed starting in spring. I'm obsessed!

Dave
Milwaukee

jimmydo2
The L brackets that you refer to are to help the base from flexing. The bottom of the base has a 11/4" lip on it I installed a quarter inch X three inch lag bolt through the base into the timbers every two feet plus two close together at the Conner's. I did tape the panels on the ends but their is no point to taping the sides.
The roof has 1/2x1" square tubing running horizontal on both sides. If I was going to subject it to the kind of winds you are talking about I probably would build it a little stronger but mine is siting in a well protected area. Mine will not see hardly any wind but I drove a fence post into the ground at the inside Conner's left the top of the post flush with the top of the timbers then put lag bolt into the timbers. That will keep it from sliding or lifting. I did not use clips from Charley's I used #10 self tapping screws with hex heads and neoprene washers on them. I bought them at LOWES. After reinforcing the conner post mine is plenty strong for my location but you could do what I did and then run a cable from the top of a conner post down to the timber at the other end use a turnbuckle to draw it tight. You could do that with all four post and then anchor the base and it would withstand 70mph winds with no problem. Strength is in how something is designed not in how thick the metal is. Charley's clips may be better than what HF sends but they won't come close to holding what the screws will.
The modifications that I did cost about 50 bucks you can get one on sale now for 599 and for a $100 you could have a stronger GH than anything on the market. For those of us who can engineer things this gh is a hell of a buy. For those who can't they have to pay that high price where someone else has done it for them.

I think I am driving my wife nuts.

I want the Big greenhouse
But I am concerned about the winds
I need more space
But where would I put the big greenhouse.
The east side of the house where the garden was.
But the Neighbor-kids threw rocks, railroad spikes and other things in the garden, they might throw things at the Greenhouse.
I have a half acre, there are plenty of places I could put the greenhouse.
But how will I get water and electric to it, if it is not near the house.
What about where we have the two Citrus trees that keep dying every year.
But that will block the view from our bedroom window.
I really want the big one
But the instructions say you need up to three helpers...
I could hang out in the big one when I need a place to hide
The big one says do not build if it is windy, you might damage it.
....
....
Um I could wait till July to build it, the winds will die down then.

and um, if I eventually want to have some citrus trees in it, the 6x8 will be too small :(

I wonder what they really mean by do not build it when it is windy...
Does 10 mph count as windy?
what about 15 MPH

But I do have a question for anyone that has a 10x12 greenhouse HF or not, how do you arrange your greenhouse

the HF is 10 feet wide, so would you have 24" shelving along each wall, with two 2 foot wide isles, with a third row of 24 inch shelving down the middle?

Jim

Jim I love your inner dialogue. I know how tough it is when you are trying to make a decision, don't worry you will figure it out.

As far as your question, I have the 6x8 and it works for me, however my husband is 6'4" and he cannot really come inside it at all. So if you are a big dude like him then you might consider the 10x12 if you have somewhere to put it.

Another thing to think about, you may not need electricity in Cali, as long as you have water (a hose would work..). I have no elec in mine and it's fine (when it gets TOO COLD I drag and extension cord in for the heater).

All that being said, maybe you can modify the 10x12 to handle the winds....

Either way, good luck...and don't be stressed, be happy...You are getting a greenhouse!

Yesterday my husband set up our 10 x 12 and it was pretty windy but it was either yesterday or having to wait until next weekend and I'm much too impatient for that. Even though right now all I can do is look at. (recovering from surgery) And yesterday we were definitely getting our March winds. Adding to that we live in the Gulf Coast. Our winds were probably gusting to 30 - 35 mph and it didn't pose any problems. He managed to get it all set up yesterday without a single problem. Murphys law was definitely on our side.

I just got my 6x8 HFGH last Christmas and we have had some really windy storms and so far all the panels have stayed put. The only change we made was to use SS bolts. And I think my husband might have added more then they called for. We used the clips that came with the kit and didn't calk or weather strip it.
You are in the same US zone in CA as I am. I am in the Santa Cruz Mts. The biggest problem I have had is keeping it cool. The temperatures really climb up fast on a sunny day.
I got from "ACF Greenhouses" for $279.00 the (A1216) ACF Ventilation System: 1 - 12 in. Exhaust Fan, 1 - 16 in. Intake Shutter, 1 - Intake Shutter Motor, 1 - ACF Single Stage Thermostat, 1 - ACF Fan Speed Control. You should get it, you will really need it.
Good thing they didn't have the 10x12 GH at the time or I would have been having the same inner conversation as you. I have already filled up the 8x6 and could use more space. More is better!

Yeah with my Scratch built that I made to winter over my plants, My Biggest problem was Overheating during the day. Well that and not retaining heat at all. When the days cooled of, it would stay within 2 degrees of the outside temp, and would balance out with in 30 minutes of the outside temp bottoming out.

I have decided that I will make the 10x12 work for me; I will reinforce the heck out of it. I am going to be growing trees, I will need the height.

ACK, I went by my Local HF Store today, "Just to Check", I should have my Money by Tuesday...
They have the 6x8 in stock $399!, but have never had the 10x12 in stock, Granted when I gave the part number to a stock clerk, and told him that it is listed on Harborfreightusa.com, he said that it is a new item and should be stocking it soon... SOON, how soon, my 20% off coupon, expires on the 18th (Does that mean I can use it on the 18th, or that the last day I can use it, is the 17th) Sigh.

I am only about 130 Miles from there Camarillo Warehouse, I wonder if I can do a will-call, and use my 20% off retail store coupon...
Leme see, 260 miles round trip call it 9 gallons of gas, at 2.60 a gallon, call it $24 bucks for gas, and 3.5 hours of Driving, one hour for The hassle at will call.
Oh, I can not forget the Stop at Canters Deli for lunch for me and my helper, so add another hour, and another $40.

Oh wait, I cannot use my car (3 door Saturn, I do not think the big metal framed box will fit in it, so I have to take my wifes truck, Yeah my wife has the truck, what can I say, she is a Red Neck Woman, I think Gretchen wrote that song for her, but my wife is better looking.) Ok where was I, oh yeah Driving the Truck, well I can still average 75 MPH, but the mileage is gonna suck, so that would be $40 bucks in gas

SO $40 for Gas, $40 for Lunch, and 4 and a half, ok call it 5 hours of my time...

Hmm, well there are about 9 HF Stores, (other than my local store), that are 30-75 miles away, I guess I am gonna have to break down and do that old fashioned thing and let my fingers do the walking. I hope they have it for the same price as the Mail order site.

Yeah, I found out on this site somewhere that the www.harborfreight.com site is for mail order/web order prices only, and the www.harborfreightusa.com sight is for retail stores, but it only shows stock items (Not what is in stock, but what they can stock), and they do not show the prices.

So does anyone live out here in Southern California, and want a free meal at Canters, and Corned beef and cabbage (my wife makes a Wicked corned beef, she slow cooks it all day), oh yeah and lots of Guinness. (Most of the Guinness will be after it is built. I will be taking lots of Pictures, and using the extra reinforcing mentioned elsewhere on this site. I will also be sinking the Frame (But on wooden supports. I will be sealing the open edges of the Panels with 100 Mile an hour tape (Also know as aluminum tape I think), and then running thin weather-stripping along the inside edges of the panels. I will buy a couple packages of Extra Spring Clips from Charlies, and probably screw in the panels on the roof, since they will not be easy to remove for the summer months. I will probably add extra Triangle corner reinforcing, Guy wires with those funny twisty things and some nice big anchors into the ground.

I have a 220 GFI for my Hot Tub near where I will be building it, but I probably should not tap into that for the greenhouse. I do have a couple of Blank spots in my fuse box (Why do they still call them fuse boxes... oh yeah I think they are called breaker boxes now), it was easy for the Guys to run the Power to the Hot Tub (About 15 minutes), but then thats what these guys do for a Living. I probably will not need power to the greenhouse, till Fall anyhow, I will be removing panels and using shade cloth for cooling in the summer. One corner of the greenhouse will be just past one of my Spare Sprinkler heads, so I can tap into that for water, and if I install timers inside the greenhouse, I can have different watering schedules for the watering and the Misting... I assume that is what I should do. One other thing I will be doing is running an extension from the clothes dryer vent to the greenhouse to have the clothes dryer exhaust into the greenhouse... Free Heat and moisture. (Most of our clothes washing happens late at night anyhow.

I figure I will till up the ground where the greenhouse is going (Should make leveling it easier), and then I will be flooring it will all the shingles that blew off my roof over new years weekend.

Ok, what I am I missing, ahh yes, orientation, if I remember correctly this greenhouse is 10 feet wide, and 12 feet deep. The greenhouse will be about 8 feet south of my garage (I already can see that gap is gonna become a place where you toss all the crap for the back yard, but it would make a good place to park my Garden Tractor). The winds here come out of the South, Southwest, I was thinking of Orienting the Greenhouse so that the door is facing west, I figure that would be better than south, and having the door on the east or north side would be awkward.

Does this orientation sound ok? Or should I really put the door on the North side?

Now a question for those who have built a 10x12,It is hard to tell from the Instructions, but it looks that the secondary brace for the vents is a separate piece of metal, so would it be possible for me to put all for vents on one side (In this case the North Side), of the roof? I do not think that having those vents facing south and opening up into a 40 MPH wind would be too healthy for the vents or the greenhouse (I am imagining a balloon being rapidly inflated), plus the wind blowing across the vents on the North Side would provide a Nice Low Pressure area, increasing the effectiveness of vents on that side.

Am I missing anything (other than the greenhouse kit?) any suggestions, corrections, or Ideas.

Sorry about writing books, hopefully most of you find it entertaining, rather than annoying

Quote-

Now a question for those who have built a 10x12,It is hard to tell from the Instructions, but it looks that the secondary brace for the vents is a separate piece of metal, so would it be possible for me to put all for vents on one side (In this case the North Side), of the roof? I do not think that having those vents facing south and opening up into a 40 MPH wind would be too healthy for the vents or the greenhouse

YES you can put all four vents on the same side.
I bought foil backed tape at LOWE'S I don't remember what band it is but if you use it be sure you get it in the right place when you put it on because you can not pull it back off. Never saw tape stick like that stuff will.
A few days ago I was working in my GH and we were having wind gusts of 60mph. I had the doors open and the wind would lift the roof panels and they would make a slapping sound when they came back down onto the metal but they didn't blow off. Since then I have added more clips to prevent that from happening again. I had screws in the center but the wind was so strong that it would bow the panels at the outer edge and then drop them a few extra clips will solve that problem. I had several clips left over because I used screws instead of clips at most locations. had screws at the top middle and bottom of the roof panels and now have clips down the outer sides.
If you want to increase the roof vents cooling ability you could do what I did and install a ceiling fan to push the heat out.
Sounds like you have a good plan. Good luck and enjoy your new greenhouse.

Thanks for the Info, both on the roof vents, and on the Winds, out of curiosty, are your doors facing the direction the winds came from?

I will definitely be reinforcing my roof panels ;)

I really like the fan idea especialy for sending down hot air, in addition to sending away hot air.

How strong are the Manual window openers? I am concerned about the low pressure pulling open the windows, even more about any that I my put solar openers on

Jim....

We had a storm here with up to 75MPH winds. It lasted 48 hours. Then slower winds for another three days. Trees went down, fences went down, and new HD antennas on homes went down. My little HF 6X8 did just fine. I think if you build the larger HF GH, it will also be fine. I have posted details on my foundation. Even with my HF GH empty, it is attached firmly to the foundation.

I used the clips that came with the HF GH. I thought about buying more clips (from Charlies), but I have not. The wind storm here did no damage, so buying more clips is not high on my list now.

I think if you have questions about wind and the larger HF GH, you can always take a 1X1 or a 2X4 and add a brace after you build it. You can always put a bead of calk on the frame before you drop in the poly. After you apply the clips, it will hold better. But, I think that might be overkill. I think good workmanship is all you need. From the questions you ask, I think you have that.

Go for the big greenhouse!!

jack

JIMMYDO2
My GH is not finished. I plan on installing automatic opener on the roof vents but at this time the vents have a bungee cord holding them tightly closed.
No the wind did not have a direct shot into the door it probably was only 30mph but it lifted the roof panels but the clips cured that. I have clips down the sides of the roof panels and screws at the top and bottom plus the center where the horizontal bracing is. That is a total of 6 clips and 3 screws per panel. I noticed the wall studs flex a good bit if you are going to sit it where it will have high wind hitting it you may want to run a cable from the middle stud to a ground anchor but this would only be necessary for really high winds.

Wow Gadenerwantabe, you have helped so much, I hate to pluck your brain for more, but I had another Idea, You said that I would be able to Mount all the vents on the same side of the roof, , well I was wondering , if If you thouht it would be feasable to use one of teh vents on the side or back of the greenhouse as an air intake vent (small critters are not a problem where I live. I realize that I would have to RIg something up for a hinge point. Or would it be better to do Some thing like was done by one Handy User on this site.

http://www.lowtechwebs.com/hf/ghwindow.htm

Not that I am trying to be cheap, Just thrifty, it seems that I can not find an automatic louver system for much under 100 bucks, whereby I can my the Automatic vent openers from Harbor Freight, or do the HF openers not work well?

I have no experience with the HF vent openers but I do remember reading on this forum that someone had one and it would not open the vent. I have no idea why maybe it was defective or it may have been improperly installed.
All panels on the 10x12 HFGH are the same width but not the same length so if you put a roof vent in the upper back it will need to be cut to a shorter length.
Then you will need to buy a hinge and buy a panel to replace what was in the roof. That would cost much more than buying a vent in the first place. I went to a surplus closeout place and found some new small aluminum windows with screens for $15.00 I plan on installing them in the back. They will have to be opened manually but on a warm day I think I can open them along with the door and roof vents and not have to power ventilate. I do plan on installing electronically operated shutters that will open if the thermostat turns on the exhaust fan.