Vented Hoop House

My biggest problem with a hoop house, or anything similar, is the fact that when I leave for work in the morning, the temperature is at its lowest (28 degrees this morning) but the temperate will rise to 60 degrees for a high during the day. Therefore, I cannot vent the hoop house before I leave for work because the temperature is at its lowest. If I don't vent the hoop house, the vegetables will cook during the day.. Because my drive to work is about an hour, I can't drive back during the day to vent the hoop house after the temperature has warmed up. Therefore, I saw this video on youtube that shows an inexpensive temperature controlled ventilation system.

I also like the idea that you just lift the whole hoop house up when you want to get into it rather than having to unwrap/rewrap etc.

Check it out.

https://www.youtube.com/watch?v=v6bWeYCV53A

The ONLY reason why I'm successful at season extension is because my wife is our homemaker and is able to take off the covers for me. Like yourself, I'm off to work early before sunrise in the winter. However, my "human vent" still complains of the job at times and therefore that vent looked appealing. I like how its set at 55 degrees. I wonder if it has a thermostat to change that temp? I do still worry that clear bright sunny days purely on the hoop house could still potentially cook the plants.

I also like the idea of something that simply fits over the bed. One consideration for that however is that in the fall you are dealing with mature crops that can easily spread past the footprint of the 4x4 dimension. They might get cramped in there but smaller leafy stuff like spinach should be fine. I also worry that wind could lift up and under it and once that happens you are dealing with essentially a large sail !!! I'm sure a few hinges would help but it would still worry me. I've thought about the cover design that fits over the bed and what I thought about to ensure better contact between the two pieces is to add rubber weather strips (door insulation) along the underneath of all four sides to stop cold air from getting in. My beds are older and although in good shape, something that went over the top would not be snug enough due to ever so slight natural warping.

Just some things to think about but I really like the vent idea. I'm gonna search for one locally. Thanks for the post and I hope you find a solution

perhaps you like to put this address up for finding

amazon.co.uk automatic green house vents.

These are adjustable by screwing the dark cartridge in or out , they can be locked up after removing the operating cartridge 7 locking pin then putting the pin back in the locking position really cold windy weather .

I have three such auto vents in my glass house , two high at diametrically opposite in the apexed glass roof ( caddy corner ? ) to let the hot air out and one at low level one on the north side of things right in the middle of the back north wall to allow slightly cooler air to come in thus also giving that very important fresh air circulation as well .

For your tunnel I'd put one low at one end and one high at the other to get the best air movements if you only use two auto vents
.
I'm sure they will be easily available stateside as they are usually made in China nowadays .
They can be easily made to open flaps outwards in the wooden sheet ends. For really warmer weather you could also make a much larger side hinged door at each end to allow you even more air flow using an " F " finger shaped keeper for a simple wooden toggle catch

I 'd suggest that you put anti cat & other pest mesh on the inside of the lower vents/ doors to keep those unwelcome visitors out your polytunnel/green house

I just found that vent from the video online at amazon for $10. However, it does state that it opens at 70 and closes at 40. Still pretty decent though.

Plantoid - I too was concerned with air circulation so thanks for your tips. If I move to this style I will be sure to add the extra vent into my design. Were you trying to post a link or a pic to a different vent? I don't seem to be able to see it.

staf74 wrote:I just found that vent from the video online at amazon for $10. However, it does state that it opens at 70 and closes at 40. Still pretty decent though.

Open at 70 and closed at 40 is still good enough for cool season plants like spinach and lettuce. However, on cold nights, I like to close my hoops at sunset and trap in the peak heat if possible for the night. The warmer the start, the warmer the temps stay overnight.

staf74 wrote:I just found that vent from the video online at amazon for $10. However, it does state that it opens at 70 and closes at 40. Still pretty decent though.

Plantoid - I too was concerned with air circulation so thanks for your tips. If I move to this style I will be sure to add the extra vent into my design. Were you trying to post a link or a pic to a different vent? I don't seem to be able to see it.

Not the vent you mention , just the actuator arm and operatingcartridge of one used in real glass & aluminium framed glasshouses

Thanks plantoid. I've seen those arms and now know what you were referring to.

BBG - Certainly trapping early evening heat will give your set-up a head start for the night. For my set-up, if the vent closes at 40, I think thats ok as the lights will keep it at that temp or possibly have it rise some. I might just experiment with a bed to see and compare. It'll give me something to do if nothing else. I didn't know you were going with season extension. Post a pic of your beds if you can. Whats growing?

I really enjoyed the video, thanks for the link

I can not get the video to run (too slow a connection). I assume the
vent being mentioned is the automatic foundation vents? Has any one
tried them and how did they work?

Today I made a hoop house with some poly pipe and plastic and finished
one made from a bought cold frame that was too short and is really a
cheap flimsy piece. That hoop house was slick and easy to make. Any ways, I am worrying about how a small space heats up even faster than my greenhouse.