What % humidity is OK for inside coop?

Discussion in 'Coop & Run - Design, Construction, & Maintenance' started by karmical, Nov 27, 2007.

  1. karmical

    karmical Chillin' With My Peeps

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    Howdy out there!

    I just bought a thermometer for inside my coop so I can get a handle on how cold it's actually getting in there as winter comes, and the dang thing came with a humidity gage as well. So, now I'm wondering what % humidity I should be striving for! Right now it's reading about 75% and I think I read somewhere that you want pretty much NO humidity in a chicken coop? So I'm wondering what the true scoop is on humidity and if this % I've got is something that's enough off from optimal that I need to try to "fix" it for the winter. My coop is 8'x10' and quite tall...my 6'4" brother can walk around in there with no problem (I have 7 pullets).

    A little more information in case it's helpful: I'm using deep litter method (pine shavings)...there's one fixed window that doesn't open, a loose fitting window that ventilates (I think) and a sort of a screen vent in the roof that allows for air movement, although there's not a fan or anything pushing the air out.

    Also, I noticed one morning when it had gone down to 20F overnight that the inside of the fixed window had frosted up (which is next to their roost).

    Any advice / opinions would be great!! Thanks [​IMG]
     
  2. speckledhen

    speckledhen Intentional Solitude Premium Member

    I've never heard a certain percentage as far as humidity in the coop. You want adequate ventilation of moisture from their poop and their breath and no leaky waterers, no wet shavings left in the coop, etc. If your window is fogging up, I'm not sure you have adequate ventilation-is the windwow single paned? If so, that's probably why it frosted up. It's a balancing act to get enough air movement plus enough warmth in winter.
     
  3. karmical

    karmical Chillin' With My Peeps

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    Thanks, Speckledhen.

    The window IS single paned. And it's not even glass, it's plexi. Sounds like I'll just need to do my best to keep the moisture down in the elements I can control. Or maybe think about putting in better windows! It's my first winter with chickens (and a coop that was already on the property when I bought the place), so I wasn't sure how truly "insulated" the coop would really be, in spite of appearances that it should be toasty [​IMG]

    Is too much moisture bad when it's cold because it makes them more susceptible to getting sick? Or just makes it harder for them to keep warm?
     
  4. Cheryl

    Cheryl Chillin' With My Peeps

    DH would also like to know about humidity, he wants to wait before venting the coop, does anyone know the percentage?
     
  5. rooster-red

    rooster-red Here comes the Rooster

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    The only humidity percentage that I've heard about for a coop is that it should be less than 100%.

    I know that at 0% humidity their lungs would dry out and they would die.

    If I have to venture a guess I would split the two , try for 50%

    Chickens can thrive in a wide range of humidity as well as temperatures. [​IMG]
     
  6. Mountain Man Jim

    Mountain Man Jim Chillin' With My Peeps

    Finally a question I answer and in a professional capacity. Per the ASHRAE (American Society of Heating, Refrigeration and Air Conditioning Engineers) Applications Handbook the recommend environmental conditions for a laying house are:

    Temp = 50 to 86F
    Relative Humidity = 50 to 75%
    Ventilation Rate = Sufficient to maintain the house within 2 to 4F of the outside air conditions during the Summer. Generally, rates are about 0.1 cfm per lb. of live weight during the Winter and 1 to 2 cfm per lb. for summer conditions. (Jim’s Note: cfm = airflow in cubic foot per minute)
    Space = 50 to 65 sq. in. per hen minimum (Jim’s Note: that’s a minimum for commercial applications)
    Light = (Jim’s Note: I should hope that BYCers don’t control the lighting in their coops)

    Some additional notes from the Handbook. Depending on the number of birds you have and their age, the environmental conditions may change. The need for heat and moisture dissipation will increase as the chicks grow. So, you may need to heat the coop for the chicks in the winter, fall and spring, but as they grow you may end up ventilating to meet the summer (and winter) ventilation and temperature recommendation.

    EDIT: So ... having posted the official recommendation, I should add some practical recommendations. The official recommendation is that you should humidify in the Winter. From a practical standpoint and considering the design of most coops, humidification in the Winter is probably a bad idea. The humid air will hit the cold surfaces of the coop, condense the water vapor into liquid water and destroy the coop within a week [​IMG] The official recommendation was written with a commercial application in mind with the poor birds in lonely little cages. Our birds will all be huddled together and will generate lots of heat and humidity in their localized area. Also, the birds will be roaming around outside during the day (can't do that on the factory farm), hence their humidity level in the coop quickly becomes moot.

    I think heating in the Winter may be warranted if you have a small number of birds, in an uninsulated coop, in a northern climate. I don't plan on it if I can avoid it, but I do plan on insulating the heck of the coop. Please note that direct gas heater (heater without a flue) (I think PurpleChicken does this) could have some issues. Aside from forcing the birds to breath in the products of combustion, these heaters put out lots of moisture. As noted above, humid air (in this case greater than 30% RH) could case problems with moisture accumulation in the coop’s structure causing early damage to the coop and, yes, the dreaded mold issue.

    I could go on for days, but I'll stop here with my diatribe ... I really should be working [​IMG]

    I hope that helps,

    Jim
     
    Last edited: Dec 11, 2007
  7. karmical

    karmical Chillin' With My Peeps

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    Honeoye Falls, NY
    Yay Jim! That's great info!

    I'm think I'm getting close now....with the addition of a little fan and leaving the heat lamp on all day, my coop gets up into the 40'sF (still a little on the cold side) and the humidity gets down to about 75% by midday (after being closed up all night). Good to know I'm getting things somewhat close to the optimal range at least. The girls seem to be doing fine with it and bedding is staying dry...so I'm hoping things are a-ok [​IMG]

    Thanks for the info!
     
  8. rooster-red

    rooster-red Here comes the Rooster

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    Quote:Excellent info! [​IMG]
     
  9. TxChiknRanchers

    TxChiknRanchers Chillin' With My Peeps

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    OK I have a Question:

    Our humidity gets to 100% here at times, and no it aint raining. Should I air condition or What?

    Not serious about the A/C but we do have HIGH Humidity(way in excess of 50%) here especially in summer. Everyone seems to be ok. I wish sometimes that it was lower but Not!
    I think its just what they get used to. I know when we went to southern California last Dec. I dried up and my nose bled.
    I was so glad to be back where the deer and the antelope play!
    So I dont know what is the proper humidity is but if you cant change it you and your chickens just have to live with it!

    randy
     
  10. Cheryl

    Cheryl Chillin' With My Peeps

    Unless a dehumidifier were to also be put in the coop, I seriously doubt it will ever be 30% or lower!!
     

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