When I purchased the used tunnel, I had intended for it to go between the smaller tunnel and the next one to the east. The problem was I left enough space to build another 18 foot tunnel there, not a 30 foot tunnel. The distance btwn the two was 35 feet. That only left me with 2.5 feet between tunnels, not good for air flow or build up of snow. Also, I did not have another space that was large enough to put it that was already in production. In order to put this tunnel in a new location, I would have to have done lots of dirt work and that would have added to the cost. I did have a space that I was wanting to build another smaller tunnel on. It was currently in outdoor production, it was level and ready to go. So, I decided to build over the smaller one. I started this project in November and I knew the ground would freeze and I would have had a hard time getting it built if I waited until spring. So I set all the ground posts, in both locations. Then I have slowly, as weather allowed, finished the big tunnel. I also have established beds in the small tunnel that I am going to continue to use in the big tunnel. I didn't want to loose these wonderful beds. I have worked hard to build my soil with compost and organic matter. Last winter this tunnel was uncovered and we had lots of rain and snow. It was very wet. That would help with any salt build up to flush it out. Also about salt build up, I have heard conflicting reports about this. I have heard a lot more that it isn't a problem. In fact one College professor/researcher presenter said he has never seen a salt build up problem in a tunnel. In addition, I had a few crops still growing in the smaller building that I didn't want to loose. To answer you question about the purlin. There is another purlin that goes down the center of the building. I was unable to put it on because I would have had to walk down the center of the smaller tunnel or hire someone with a bucket truck to come out and help put it on. Also, I didn't want to remove the inner plastic before the outside one was ready for plastic. Now, I have the plastic on the big tunnel, I am going to finish the doors on the big one and take the plastic off the smaller one. Then remove the ribs, add the third purlin to the big one, and then remove the rest of the small one and move it to its new location. About cross bracing, I was wondering about adding that too, but I have contacted the company, Stuppy's and they said they are engineered to not need them. Also, we don't get the snow that you do in the Northeast, so I am not too worried about it. The person I purchased it from lives one hour away and his location was very similar to mine. Top of hill, no wind break and he never had any problems. So I am trusting the company and the previous owners experience with that aspect. Will I add some cross bracing, maybe, just in case. Thanks for the questions. Jay

Ah. I hadn't thought of that, as I would just cut to size. 3'3" is pretty tall for a low tunnel. Lots of extra material to purchase that would go to waste. Regardless, AIUI the Johnny's pipe bender will give you a fixed height and you'll have extra material at the end to cut - that is: if you were to bend a 10-footer with that thing your base would be wider than 6'. I suspect that the directions will tell you how long of a pipe to start with to get a 6' radius at that height (but you should make your own bender anyways). Dan

Not a bad temp. equivalent is 72 degrees in the english system

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