How to ventilate a hoop house coop for winter?

[amunk01]

Ok. This is my first winter with girls. Im located in central Oklahoma. My coop is basically 8' x 10' standard hoop coop made with cattle panels covered with a very heavy tarp (its actually two) that covers both Sides except for ~6-8 inches from the ground, and covers the back completely. The front side/ door is just hardware cloth, but i intend to cover it with plywood and heavy plastic to prevent drafts if need be. My concern is without any overhead ventilation in the tarp, will I have a major problem with condensation, ammonia build up, etc.? I dont see how the tarps are breathable so how do i ventilate it without exposing the girls to the elements? I have 20 birds in there (at night only), but im confident i need some type of ventilation, right?? I need some help please.

 

[Duckworth]

I live north of you and have cold, windy, and snowy winters, too. Looking at your photos, I wonder whether when you put the plywood on your door, you can cover just the lower two-thirds of the door and on the top third, put either a large return air vent cover, with louvers pointing down to keep snow from falling in or construct a simple awning of plywood to allow venting without snow or rain getting in or wind coming in. You might have to make the bottom of the awning cover overlap the next lower panel some to keep enough wind out. I'm thinking a piece of plywood with a shallow right-angle triangle on each side to hold the awning at the angle you want from the door and to seal out wind coming from the sides. I hope that makes some kind of sense. You could even just cut a simple frame for the awning and staple pieces of a tarp to cover it.

 

[21hens-incharge]

I like @Duckworth's idea. I think that may be your best bet.

 

[Duckworth]

If just one third of the door isn't enough, you could put awning covers over the two upper thirds. I don't know how weather tight your plywood panels will be, so don't know how much incidental ventilation will be happening. I know there's a formula for the amount of vent space compared to the amount of floor space or number of birds, but I can't remember what it is or where I saw it on this site.

 

[21hens-incharge]

Each bird needs 1sq foot of ventilation is what I have read.

I didn't measure mine but I do know I have tons of available ventilation.
On good days the windows get opened on icky days and at night I close them BUT there are also open soffits on my coops so venting is always there.

 

[aart]

I think if the rest of the coop is pretty tight(no openings) leaving the front open might work fine. Wind can't blow thru if no other openings. Might depend on your prevailing winds.

 

[Duckworth]

By that standard, the OP would need 20 square feet of venting. That probably exceeds the size of the door. Now, I'm wondering whether it might make sense to run a taught line or pole a foot or so above the lengthwise center of the top of the hoop so that an additional tarp can be installed over the top of the hoop with ventilation space between the hoop roof and the added tarp. He/She would then need to cut ventilation holes in the existing roof tarps to allow ventilation through the roof into the space between the tarps.

The other option would be to remove the existing tarps and fold each in half, attaching one folded (for double thickness) tarp to the cattle panel two squares from the peak on each side, then putting the new tarp over the taught line to allow air to escape through the top and out either end. The issue may be whether the coop is oriented so that the prevailing winter winds would be blowing right through the vent space and into the coop.

I'm no engineer and have tried to resolve these dilemmas as I was building my duck house and pen. But how successful I've been at it remains to be seen. The fact that the hoop house isn't your birds' full time home may help.

 

[amunk01]

Sorry! Of course, I posted and then my phone screen died! Finally got a replacement. Thank you for the great ideas! I like the idea of louvers across the front. I wonder if I could build louvered coverings for on each side of the door to deflect any direct winds (although the front faces east so direct wind isn't the most common but you never know in OK!) but allow for ventilation across the entire front of the coop. Thus supplying more than the recommended 20sqft of ventilation. Then just staple clear 6mil plastic on the actual door to allow light but block wind. However, does ventilation have to be overhead? Or will the purposed suffice? Aart, to clarify the remainder of the coop isn't exactly air tight. Both lengths of the tarp leave about 6-8" gap along the base. The entire back is completely covered though so front to back draft isn't possible, but air can flow across the floor easily. All my birds roost, and the roosts are about 3ft high so I think that is ok. When standing in the coop on a really windy day, the roost area/ coop doesn't feel drafty or breezy to me (maybe it could to a chicken, but how to tell?), but it also doesn't feel completely stagnant. I just added the larger tarp for the upcoming colder weather. During the summer the sides and back have about 24" open space from the ground up allowing much more air circulation, and everyone has been happy and healthy. I think I may build louvers for each side panel in the front and go from there! I'll update when I get those finished. Any more opinions or observations welcome! I appreciate the feedback.
~Alexis