deep litter method not working in my chicken coop -- odor too strong

I'm trying to start the deep litter method in my coop but tonight I cleaned it out because the odor is too strong.  I must be doing something wrong.  My coop has a floor area of about 18 sq. ft with 8 hens in there only for sleeping.  Half the coop is about 2 feet tall and the other half is 4 foot tall.  They free range all day.

I had about 3 weeks of old wood chips/poop in the coop but the smell was getting bad.  I've got two decent size air vents in the coop as well.  I've been adding new wood chips one a week and raking them into the old wood chips.  Also the coop door is open all day and temperatures are around freezing at night.

Any ideas on why the smell is so high?  I wanted this to work to help heat the coop at night.  The coop is partially insulated but I'm not planning on heating it, I didn't heat my previous coop and it the hens were fine, but now that I have a bigger coop I thought I could give the deep litter method a try.

Thanks.

Three things come to mind:

1. Insulating coops... this likely means you have reduced air flow. I'm not sure what "decent size air vents" translates to but it could be not enough. Chickens are WAY hardier than many people think. Like -20C is ok.
2. So along with air flow, you may have a moisture problem. Or rather, low air flow means too much moisture.
3. You may not be using enough chips. What happens if you put in 3-4 times the amount of wood chips? I use leaves myself, or a combination of small wood chips from brushing + leaves. Never had a problem at all. If it smells, I add more and usually the smell is gone within an hour. I try to keep it 6-8" deep at a minimum.

Finally, I think there is this misconception about what deep litter is. You are not composting in the deep litter per se, that's not the point. That poop and litter, if it is heating up enough to compost actively, is going to smell and cause problems. In that case it's likely too wet, which means too little air flow.

I'm pretty sure your problem is just air flow. Dry is good. Not completely dry, you want biological activity just not composting.

What's the smell? Ammonia? Putrification? Urea? Mildew? Fungi?

More info: There are two air vents about 4" square located at either end of the coop on the side walls near the ceiling.  I only have the litter about 4" deep.  The smell is ammonia like.  Doesn't smell like pee or poo.

I wonder if I do still need more air.  I can definitely add more wood chips.  And I've got lots of leaves I can add.  What do you think?

In my opinion, you need a LOT more ventilation and more chips.  Chickens should not be in a wind, in a cold climate, but should have a lot of ventilation.  If they are kept dry and out of a wind, they can stand a lot of cold, and may even be more comfortable.   Start by adding more bedding, and if things don't improve, add more ventilation.

Yeah, that sounds like it needs a lot more ventilation for that many birds in that small a square footage- it's the moisture in their breath that I suspect is causing your problem.

You might also just need to turn the bedding yourself every day or two, if you aren't already. I think people assume that the chickens will turn it, but if they're only in there at night, I don't think they end up doing that much turning. Without some good, deep turning, it will turn anaerobic (thus the stench). Maybe after a while of turning it yourself (pitchforks work great for this, but a normal rake will do if you have no pitchfork), the good bacteria might become numerous enough that you don't need to do it so often.

I was looking for the book where I first read about deep litter. It was published in the 1940s and was excellent, but had a very generic name. I gave the actual book away some time ago.

But I found this, which does mention an article from the late 40s... not the same but close:

http://www.plamondon.com/wp/deep-litter-chicken-coops/

Including this: "It’s labor-saving. If you’re spending a significant amount of time messing with the litter, you’re doing it wrong."

To me that's pretty much the key of any permaculture practice. It's up to you to decide what constitutes a "significant amount of time" but for me that was limited to putting in new material. I've never turned it. Anaerobic decay produces a very different smell and it doesn't sound like that's what is happening here. Worth considering of course, but in theory that shouldn't happen in deep litter, even without turning.

Thanks so much for the link.  After reading what has been learned from so much experience, I feel more confident now continuing on with trying the deep litter method.

I added a lot more wood chips and I'm leaving the nesting area lid open a crack during the day and that seems to have solved the ammonia problem.  I think I'll add even more wood chips.  

I could probably use more ventilation too, but I'm hesitant to cut another hole in the coop.  I understand that the chickens can withstand cold temperatures, but it can get really cold here some nights in the dead of winter, down to say -30F overnight.

My coop has large openings which can be closed on the coldest nights.  In warm years I might leave both windows open, in cold years I may close only the one on the windward side.  For my approximately 36 square foot coop I have approximately 12 square feet of open window.  This is for a warm climate, but might be fine for a cold climate if the openings can be covered during the coldest times.

If you'd like I can take photos tomorrow and post them to show the design.

I have deep litter, and I had ammonia buildup in the middle of last winter when we hit a thaw after a long period of frozen temps. It seems that here, for the most part, the bedding mummifies the droppings, drying them out, but when it was too cold for that to happen I got a lot of layers of moist all at once. Normally I go in there every couple of days and fork a thin layer of straw or hay, or wood chips, over the roost poo area.
 In general I love it, hardly any smell and a head start on compost. I am trying mixing some layers of char this winter along with the bedding. See if the charcoal helps absorb some of that.

An update, I did end up getting ammonia fumes with the next thaw. I cleaned it out and replaced the bedding, and this time I am lifting and tossing the droppings as they are deposited rather than just tossing more bedding on top. As Nicole said, the chickens do not turn it, so this dense pile is there, and during the the winter there is also the added factor of the droppings freezing rather than their moisture being incorporated gradually. Another person suggested having a more diverse mix of bedding in place, dried leaves etc. Still planning on using char as I think it did help until I ran out of it, and it seems a perfect way to charge the char.
  One thing, she was saying that a deep litter bed shoudl be composting. Mine was either bone dry in summer or wet when it thawed in winter. She was saying it should be dry on the surface but moist in the interior so that it can compost, thereby allowing beneficials to flourish, and without ammonia fumes. I will be trying this, I have a wood floor so did not want moist, but will line the roost problem area floor with plastic to protect thet part and see how iit goes this summer.  Using it in summer, even dry, has been great in terms of low odor and reduced flies.

I second the air flow problem. However, I think there's something else that no one has mentioned. That is, in my experience the deep litter method will not work in that small of a coop, especially with the amount of chickens you have in there. Please correct me if I'm wrong, but I've read somewhere that there's just too much poo per square foot or something, and usually not enough air flow.

You need quite a substantial amount of bedding to do this method and I've found it works in my coop, but it's 10 x 14 feet with only 8 birds. I previously had ducks in there, too, and I'll tell you ducks are just too messy for that method.

If your coop is only 4x5 or some such, I'd just clean it out on a regular basis and compost the litter for the garden. Be sure to wait a year so any pathogens in the litter will be killed before putting it on the garden.

I have ducks, and deep litter can work for them, but it just has to be done a little differently. I've found a few ways that work. I have a 8x8 duck house with four 10x18 inches nesting boxes. There's lots of airflow in there, too. I've had between 8-20 ducks in there. I don't have any bad smells in there, with either method.

(1) To Minimize Work and Cost of Pine Shavings. Only feed the ducks a little amount (1-2 cups for 8-20 ducks)to lure them into their house. Give them the rest of the food about an hour before you put them away to maximize foraging and minimizing poo in the house. Turn the bedding with a pitchfork 1-2 times a week. When you clean the nesting boxes, spread that bedding over the rest of the house. This gives you cleaner eggs and helps dry out the rest of the bedding. Also, use a pail in their house for water, rather than a dish. They can still clean their bills but won't be in there splashing around.

(2) To Maximize Poopy Bedding to Use in the Garden. Right now, I'm really wanting/needing lots of poopy bedding for building up garden beds and mulching around perennials and potatoes. I feed the ducks all their food when I put them in their house. In the morning, I put a dusting of new bedding over all the poo, while also putting the dirty nesting box bedding around the house, while putting clean bedding in the nesting boxes. This only takes like 3 minutes.  1-2 times a week, I turn the bedding with a pitchfork. About two times a month I can take out a wheelbarrow of bedding to use in my garden. This uses 4-6 times a much pine shavings than the first method, though, but I have a more controlled application of poop in my garden.

 

I second JW Richardson's idea to add charcoal.  Biochar has been shown to absorb 90 times its volume of ammonia gas.  Mixing Biochar with the woodchips should go a long way to helping out.  It will also help out when this is cleaned out into a compost heap.  20% Biochar by volume in a compost pile really helps it heat up faster and hotter and gives much better final compost since it retains more of the nutrients that would have flashed off or leached out of the pile.

I agree with the suggestions for increased ventilation and for a variety of materials, wood chips break down slowly, I suggest adding straw and wood shavings to the mix, plus whatever you have available for free (Leaves, garden wastes).  The most important thing though is that if your birds aren't scratching for at least a couple hours a week you'll have to turn it yourself every day.  If it was me I would not try this method without the birds turning it.  Better for your back to pull it once a week and toss into a compost pile that's more convenient to work in.   I have 30 birds in 120 sq feet cooped up about 1/2 the winter, there is no smell except compost smell.  Happy Spring!

J W Richardson wrote:I have deep litter, and I had ammonia buildup in the middle of last winter when we hit a thaw after a long period of frozen temps.  

Exactly.  I had to clean mine immediately when that happened.  My next coop will have much more ventilation.  I'm not sure my wood floor works the best either.  Maybe ground contact would help?