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20 Oct 2008

In Search of the Fabled Permaculture Chicken/Greenhouse

For many years I have taught permaculture courses, and like many who do so, I start my courses with the Tale of Two Chickens.  This is a very useful way of looking at inputs, outputs, and the science of maximising beneficial relationships, and it concludes with describing one of permaculture’s Holy Grails, The Chicken/Greenhouse.  However, now, as I stand on the verge of actually trying to make a chicken greenhouse, I am finding it very difficult to find actual working examples of chicken/greenhouses.  Might I have spent years unwittingly promoting a permaculture urban myth?

The idea is straightforward and works brilliantly on paper.  Patrick Whitefield in ‘Permaculture in a Nutshell’ sets it out very clearly (you can read it here), and you can read the thinking behind the Chicken/Greenhouse  hereThe picture below is taken from ‘In a Nutshell’, and captures the essential idea, which is that by placing the 2 elements of chickenhouse and greenhouse together with the proper orientation, you enable, via. good design, interactions to take place that otherwise would not take place and would require energy inputs to make happen.  For example, the warmth from the chickens keeps the greenhouse free of frost, the carbon dioxide from the hens benefits the plants, and so on.

On paper it is simplicity itself, and has developed a kind of iconic status as an all-round Good Idea.  I regularly see people have ‘aha!’ moments when I teach the chicken/greenhouse, lightbulbs coming on in brains around the room.  In practice, I am starting to wonder.  I have spent the last couple of days putting up the frame of my new greenhouse, build as an add-on to a south-facing wall off my garage.  The greenhouse is 8′ by 16′ and is a deeply thrilling addition to family life. The picture to the left shows the west-facing aspect of it to which I want to affix my chicken house.

And next, here is the chickenhouse, a recent acquisition from a former Skilling Up for Powerdown student, who offered it in exchange for our going to collect it (she was moving house… it is not a regular outcome of the course that people, at the end of the course, get rid of their henhouses…).  It is a well built timber hen house about 4ft by 4ft, and the picture to the right shows the end of it that will be joining onto the greenhouse.  As you can see it has a vent at the top.

So, my question has been how do I most successfully join these two elements together, and has anyone done so, and most importantly did it actually work?  I remember in Ireland meeting someone whose father kept 5 chickens in his conservatory, and swore it kept it frost free… I also remember seeing somewhere a photo of one built at the permaculture project Graham Bell developed in Scotland, the name of which escapes me at the moment, but I don’t remember where I saw it.  I have been looking around on the Web, and found case studies of chicken/greenhouses here, and here, but none of them are especially informative.  In search of a photo, one link (here) that promised a picture of a chicken/greenhouse, has it so far away in the picture and concealed behind trees as to be entirely useless.

What I am looking for is plans, designs, drawings, as well as articles by people who have built them, tested them, evaluated if they work or not, and who can offer their insights.  A couple of hours spent rummaging through my permaculture books and magazines, and a couple more on Google, have produced virtually nothing.  So, in the belief that I have been missing something, and that actually the world is populated by hundreds of well functioning chicken/greenhouses, I am putting out to you all for your thoughts.

My questions for both permaculture practitioners as well as for any engineers out there who may have thoughts to share are as follows;

  • What is the best way to connect them together?  Should I just take the side off the chicken house altogether and replace it with chicken wire, or make vents from the top and the bottom of the hen house coming into the greenhouse, or is there some other way of maximising the effectiveness of the heat exchange?  Presumably the place where the warmth from the chickens enters the greenhouse should be as low down as possible?
  • Presumably also the hen house needs to be as insulated as possible, so that any heat generated does go into the greenhouse rather than out through the walls?
  • Is it necessary to be able to close the vents at any time so they don’t interact with each other?

So, this is a request for the collective wisdom of the Permaculture movement to rain down on my little chickenhouse…. help me out here.  Of course it might be the case that the ammonia produced by the chickens is such that any growth in the plants is simply burnt off by the accumulation of foul gases, or that if one forgets one summer morning to let the chickens out early enough, they simply roast in a what is unwittingly a highly effective solar oven.  Any thoughts (and in particular photos or design advice) gladly received.

Comments are now closed on this site, please visit Rob Hopkins' blog at Transition Network to read new posts and take part in discussions.


20 Oct 11:12am

When visiting Sepp Holzer’s place with David Holmgren a few years back a similar thing happened. David admitted that although he had taught about Pig Tractors for many years he had never actually seen one that worked until that day. I imagine there are many Permaculture Solutions out there that have been handed down through the ages until no-one has any contact with the original source anymore.
I think your questions answer themselves, and that your site and local will demand specific solutions. On the point of heat interchange: make sure the chickens don’t roast in the summer (or rather only when you want them to).

Mark Forskitt
20 Oct 11:36am

I can’t help with the chicken greenhouse. But I can comment on keeping chickens in a house in a fruitcage with autumn raspberries. It works surprisingly well. The chicks do scratch up the shallow roots a bit, but they also keep the insect and bug population in control. And of course they help keep the ground fertilized. Only one of our eight hens has developed any real taste for raspberries.

Graham Burnett
20 Oct 11:55am

Hi Rob, as an urban vegan I wasn’t comfortable with using the ‘chicken greenhouse’ parable when teaching permaculture inroductory courses, so instead developed my own ‘urban links’ session, whereby students discuss solutions to 5 problems, ie, allotments to alleviate lack of access to good quality food, LETS to allieviate poverty, community gardens to replace derelict land, community composting to deal with bulk green waste ad bicycle lanes to improve transport and congestion. I then make the point that these are all grat ideas but none of them are ‘permaculture’ – we then start to link and connect these 5 elements, and then they become ‘permaculture’! Again though the problem was thinking of an actual working example of such a model to show that this isn’t just pie-in-the-sky idealism – I usually mention Green Adventure, a project based in South Lodon that actually did encompass allotments, community gardens, bike trailers, LETS and composting schemes, but is now, to the best of my knowledge at least, defunct.

But more recently of course its also a great model for what a develped Transition Town would look like!

Simon B
20 Oct 12:58pm

In Mozambique I visited a project where chickens were kept in houses built from slatted wood on stilts over fishponds, so the chicken shit fell directly into the pond, thus feeding the fish. The chickens had a drawbridge that was raised at night, keeping them safe from wild predators (probably not so much of a problem in Devon) and unable to escape as they were surrounded by water – genius!

Maybe you could take it to the next logical step and build a chickenhouse/greenhouse/fishpond combo?!

Albert Bates
20 Oct 1:49pm

Hi Rob. We have a cob poultry house (ducks nested lower, chickens on roosts) adjacent to our straw greenhouse but ne’er the two combine. In actual fact we discovered that our hothouse practice almost always included new starts in one section and the chickens were ruinous if left untended, even bantams. We have raised beds and sunken walkway, and the back wall is exposed straw bale. Keeping it frost-proof is a simple matter of watering in the evening, including the wall, because the straw then undergoes an exothermic reaction and heats the interior space nicely. We have to change out the bales every two years or the roof begins sinking on our North side. No loss there, the mulch is always needed and the process only takes a few hours. Another frostproof measure is to pile fresh manure (horse, cow, human, mixed with fodder) on the South side below the poly glazing. The steam on cold nights rises as a curtain, reducing the heat loss through the poly. The chickens come through and work the pile for worms, etc. during the day, so we don’t often need to turn it, just push it back up if it spreads out too much. We occasionally let the chickens into the greenhouse for supervised visits, enough to put most insects on notice. Aphid control is accomplished by the straw and cob sauna on the other side of the greenhouse. We have a hot tub that drains out through pipes under the raised beds, and that keeps soil temperatures well above air temperatures, a condition that aphids seem to loathe. This whole system appeared as part of a photo essay in Vanity Fair last year.

Hope this helps. Ounce of experience beats a pound of reading.

Marcin Gerwin
20 Oct 2:20pm

Hi Rob, the greenhouse heated with a “chicken breath” was built succesfully by Anna Edey and it is described in detail in her book “Solviva” published by Chelsea Green.

Best of luck with your project.

risa b
20 Oct 3:27pm

We have a 12X24 foot building with good southern exposure, which is 2/3 poultry, 1/3 greenhouse/potting shed. Sometimes a sheep has shared the barn side with the chickens, ducks and geese.

Noted, starts and chickens niot a good mix. I’ve even had to stone-mulch fruit trees because of same. But having the brick-floored greenhouse in the same building with the chickens, with a thin wall between, seems to be a good thing all around, in terms of heat balance.

20 Oct 5:00pm

Hi Rob,
I think a few other teachers realised that there probably wasn’t a working example of a chicken forage system and Phil Corbett was going to design one. Dont know if it actually happened but it could be worth getting in touch with him via “Cool Temperate”

20 Oct 6:15pm

I helped build a rather large henhouse attached to a greenhouse in Snowmass, Colorado years ago (at a Benedictine monastery).

The problem was that the ammonia in the chix droppings killed the plants, so the thinking was that you would have to do a heat exchange solution rather than direct heating via air movement.

Maybe just a few hens would not cause this issue, the monks actually had a going concern with hundreds of birds.

Jill Robinson
20 Oct 8:13pm

Hi Rob,
I think you’ll be interested in this article. He brings the chickens in at the top of page 3. Also puts worm bins under the walkways.

Jill Robinson
20 Oct 8:25pm

There’s a good picture of the chicken end of the greenhouse here: Close up here: A condensed version of the Mother Earth News article, with great enlargeable pics, is here:

Tim Thomson
20 Oct 8:55pm

Surely the way to go is to put the chicken house inside the greenhouse, with the doorway facing out, and leave out one pane of glass so that the chickens can get out to their run?

20 Oct 9:13pm

Hi Tim,
Indeed, I was thinking of that, but you can’t leave their door open all night because of foxes and the like, and in the summer, if I slept in late and didn’t get to let them out until mid morning, they may have all suffocated to death!! That’s why it strikes me as best practice to put them on the outside, but do so in the way that maximises the potential exchanges between the two….

Katy Duke
21 Oct 2:33am

You can get automatic pop-hole openers/closers – see (one of our Sustainable Frome members has one if you want some feedback), but I’m sure there are others. Sometimes the chickens need a bit of ‘training’ to go indoors but will roost in trees if they don’t make it – the special breeds are worse than rescue chickens or bog standard layers. I like the sound of your plan, might review our ideas for a new house & run and clamp it on to the greenhouse – this time we are making a serious enclosure cos we’ve suffered too much from daytime foxes in the past, and an auto-pop is top of the list of purchases as forgetting to shut or open used to make me feel guilty!

Danny Ballard
21 Oct 7:46am

Hi Rob,
It’s an interesting concept but I would be surprised it the chickens could generate enough heat to keep the green house frost free. However I could be wrong. Your chicken house would need to be very well insulated and sealed to prevent any loss of heat. A small electic fan and ducting would be needed to draw the warm air down from the well insulated ceiling of the chicken house and though the lower part of the green house wall. You could use a solar panel and a small battery for use at night when you need it most. The air inlets would be in the bottom of the chicken house.I would also try to have as much thermal mass in the green house to hold and release the heat of the day through the night.You would also need to consider the comfort of your chickens. Happy chickens lay more eggs. You would also need plenty of openable vents to let the heat out during the warmer months in both the chicken house and greenhouse. Double glazing of the greenhouse would also help even if your just use some of that shink wrap stuff you can fit over the frames.The chickens run would be out to the side of greenhouse/chookhouse as they will still have solar access for at least half the day. Have a look at some info on solar passive design. It may give you a few ideas. Good luck.

Patrick Whitefield
21 Oct 8:02am

Hi Rob,

Touché! For all these years I’ve been teaching about something I know only from theory! Actually that’s not quite true. I once saw one on the smallholding of an old permaculturist called Tid Tidy. I haven’t seen him for years, but his place is in the 1994 edition of The Permaculture Plot. 
 01794 301234
The Anchorage
Salisbury Rd
Hants SO20 8BX
He may or may not have e-mail by now.

As I remember it, the chicken house was as big as if not bigger than the greenhouse. (He sold eggs and had other protected cropping areas.) One crucial design point is that the division between the two structures was a sealed polythene sheet. This is important otherwise the dust from the chickens covers the plants in the greenhouse. Ventilation to stop the chicken house getting too warm in summer is important.

That’s about all I can remember.

I think one of the key facts is to establish the desirable ratio between the number of chickens and the volume of greenhouse. Intuitively, looking at your pics, I’d say you’re low on the chickens. But this is likely to be the case in most domestic situations.

Best of luck.

Love, Patrick

PS Thanks for raising this. I’ll follow up some of the replies you’ve had which offer some actual experience with chicken-greenhouses.

21 Oct 3:19pm

There are elements here of what I call “green i-manure”. (The “i” is for “information”.) Wonderful enthusiasm over really cool ideas- which may not work, at all.

All too often the enthusiasm is generated by someone who has JUST built the practice, and actually only operated it for a month or two.

Show me ONE someone has operated, happily- and profitably- for 5 years- at least- and I’ll get interested. Show me TWO – and I might build one to try myself. 🙂 Show me THREE – and I may tell others about it.

For example- personal experience here; a device like the “automatic pop-hole opener” – is fine- until it isn’t. You’ll come to rely on it doing its job. Then, one day- you wake up late, discover that (for example) a mouse chewed through one of the electric lines overnight, and today it didn’t work- and all the chickens are dead.

Actually- that awful event is guaranteed to happen, eventually. If you really don’t want it to happen- you need to install 3 (not 2) totally separate doors, each with its own separate operating system- so that when one fails, or two (much rarer, but still probable someday) – one will still be functioning. Triple redundancy gets expensive.

Lots of material for long conversations on this topic!

And huge congratulations on the Schumacher!

21 Oct 4:23pm

I agree with Greenpa on triple redundancy, and would like to go further. Your triple systems need to be as separate as possible, as 3 electrical systems can all get knocked out by a short circuit, a blown fuse or a power cut. It’s better to have one electrical; one mechanical (e.g. a slow hour-glass timer where the weight of the moved sand moves a catch); and one based on animal behaviour: i.e. if the chickens congregate in one area of the henhouse at release time only, their weight on the floor in that area operates the door.

Congratulations on the Schumacher.

Albert Bates
21 Oct 7:44pm

Very Wallace and Gromit!

21 Oct 10:07pm


We don’t have a chook hot house (don’t need it here in the subtropics) but if I was going to build one…

Create a nighthouse for the chooks in the greenhouse. Ensure it is ventilated enough that they don’t suffocate if you leave them in a little late.

Have an entry/exit door that leads outside into a run. So they go in the house to roost at night keeping your plants warm and happy. The chooks are warm and happy and you release them into a yard during the day where they can’t eat all your greenhouse goodies.

We’ve created something like this with a chook tractor. Safe secure night roost away from the pythons and let out all day to scratch up the lawn. And I’ve left them in a little late (at times) and they’ve survived – even here in the humid heat of Queensland.

Good luck,

22 Oct 4:51pm

Hello. I read your article and about your need. About 20 years ago I came across an American women named Anna Edey, after listening to a CBC (Canadian Broadcasting Corporation) radio program. She was describing how she had created economical greenhouses combining solar processes and animals. Investigating her work was quite interesting, and in your case, her ideas
might be of some value and further investigation. Below I have provided some basic info and a website for you to start your search if you are interested. Good luck and have a good day!!

SOLVIVA Solar-Dynamic, Bio-Benign Designs – Offering Better Ways to Live, at Less Cost Today and Tomorrow.
by Anna Edey
RFD 1 Box 582, Vineyard Haven, MA 02568. Tel: (508) 693-3341 Fax: 693-2228 e-mail:
Solviva designs offer sustainable ways to live. Here are the descriptions and prices of the various available Solviva designs that have been developed over the last 20 years. Most of them are drawn to scale, but are not full-fledged stamped architectural plans (we are working on that, but they will be far more costly). However, experienced people should be able to build from these drawings, with some additional consulting time. Many detail options for windows, joinery, glazing etc are left up to the wishes of individuals.
It is essential to understand that significant changes to these designs, such as reducing the number of vents, or widening or narrowing the growing beds, or reducing the volume of water mass, may significantly reduce energy-efficiency and productivity. Appropriate amounts of consulting time may save considerable amounts of time, money and frustration.
The various Solviva designs can be modified to be larger or smaller than shown on these drawings. Custom design is also offered.

24 Oct 12:37pm

From Matt Dunwell at Ragmans Lane Farm ( by Rob)

Well I guess all good parables have a bit of mythology to them – did anyone ever do that whole prodigal son thing?

Having had my adult life entirely disrupted by Mr Mollison giving a two week PDC course at Ragmans in 1991, I cast my mind back over the practical trials we have done over the years many of which stem from that two week adventure. The cupboard is bare when it come to chicken greenhouses.

We have done Chicken Tractors on a small scale, fed chickens from our pond (a bit) but not combined them with a greenhouse.

I think in general the chicken fable works well for most of the other elements, but one reason why they are not used widely in greenhouses might be that it is only a marginal benefit, and is outweighed by the design constraint of having your chooks housed permanently against a greenhouse. For instance the victorians found out pretty early on that heat from manure was the most efficient combination of animals and greenhouses, having composting muck heaps under their staging. This was then used on the beds in the summer. Perhaps this might be the most practical combination that fits into the chicken greenhouse story. So instead of helping with your greenhouse design I am proposing a heretical change to the chicken greenhouse parable.

It might be an interesting codicil when teaching to wait for the penny dropping moment to pass, then to allocate importance to the various different relationships within the system. Ie is the space under decking more important for storing pots/compost etc than to have a chicken egg box under there? If you need access through the greenhouse to get the eggs out would this be better used as growing space inside a small greenhouse. Ie trying to find that point in the design process where too many elements starts to seriously compromise how it all works. Etc etc I am definitely in grandmothers sucking eggs territory here.

Pictures of chickens sitting obligingly in the laying boxes that are then designed to tuck under greenhouse staging are a bit hopeful. In my experience you really want them to spend as little time as possible in the laying boxes, and in practice they roost during the coldest part of the night, when you would want them to heat the greenhouse, only to visit the laying boxes in the morning.

However in the spirit of adventure here are some thoughts –

I think putting the chicken coop against the greenhouse and taking out the wall in between is too much major surgery. On this small scale you could try something less committing like joining the two elements with a 100mm pipe (osma pipe ). This could run gently uphill from the coop to the underside of your staging in the greenhouse, and have a return pipe about 24” lower flowing gently down to the bottom of the coop. It would work better if you insulated at least the top half of the coop (above the flow pipe) to reduce heat loss. This would mean you could experiment with the system. If its too dusty, put a gauze over the flow pipe, if not leave it off for better flow rate. If you want to shut it off for any reason you could put a lid on it! Lagging on the pipes would help and the shorter the length of pipe the better. You would need to vermin proof it. If I didn’t work you would only need to put two patches of ply over the holes and you are back in business. If on the other hand it was a success, it might pay to think about how to integrate the two systems more – a sort of bit by bit design approach, with lots of escape pods if your strategy isent working. Worked for Darth Vader.

Keeping frost off the greenhouse is a great asset. Stopping it overheating is just as important, and a simple Jemba opener might be the ticket if the client is called away to high profile policy meetings and keynote speeches. (

Good luck in your mission Rob

You are as ever forging ahead to the outer limits of the permaculture Galaxy.

Andy Langford
25 Oct 12:41am

remember visiting Tid Tidy, poultry keeper extrodinaire at ‘The Anchorage’, Hamphire, England and permaculture designer around 1990, who had trialled a chicken greenhouse design over quite some time and who let us know that, for his design (vertical chicken wire screen between the chicken zone and the plant zone), dust raised by and from the chickens was a major problem as it had covered the leaves of the plants in the adjoining greenhouse both suffocating the plants and making them hard to wash for human consumption. This was a 25 bird size design. He was not inclined to do another one at the time.

[…] that this is the very same man who earlier in the week was wondering whether it is possible to combine a chicken house with a greenhouse. Welcome to the wonderful world of […]

Jenn Hart-Mann
18 Nov 2:01am

I am in the process of building something similar, except it is a composting greenhouse, meant to generate a hot/humid environment in the winter to break down compost (livestock manure, paper, grain, old hay, bedding). What I am wondering is has anyone built something like this for use with chickens. Seems as though very mutual relationships could exist: free chicken forage (eating grain from manure, weed seed, and bugs, digging compost, adding chicken poop, warming chickens, and warming compost area. Chicken house would definitely be housed outside greenhouse area and chickens could free-choice forage in greenhouse or go into the chicken run if greenhouse got to warm….?

21 Nov 4:26pm

Andy Langford- very useful information! Rob, and everybody- something WISE the Transition Movement could/should do- is keep a Journal Of Failures.

The rest of the world does NOT do this; and should- obviously. But we don’t. Think how incredibly useful it would be to be able to pick up a catalogue of past mistakes; and be able to build on them.

Keith Johnson
22 Nov 2:51am

A chicken coop CAN be left open 24 / 7 IF you use a doorway like the one pictured here:
A low-strung electrified wire wraps around Darren Bender-Beauregard’s chicken coop in Paoli IN, and is attached to this metal plate at the entrance. The chickens hop up and are not shocked unless they have one foot on the ground…but they always hop up….unlike the unwary raccoon, possum, skunk, snake, etc., who learn REALLY fast not to repeat the attempt. Darren found he could leave the coop open full-time and never worry about predators.

Richard Telford
22 Nov 5:19am

I built a greenhouse / chook house in 2000. The heat exchange happened with the nesting / laying boxes and also the dark gravel on the floor of the greenhouse. Download the pdf of the project here:
None of the plants in the greenhouse suffered from frost, but this was in Margaret River (near the beach) in Western Australia.

susan socks
23 Nov 9:04am

I live in Vermont, USA, and have recently built a 20’x50′ passive solar hoop house. In the summer it provides a extra warm, sheltered space for heat-loving crops which otherwise would not make it in VT. The sides roll up manually, so it must be opened in the day and closed up each night. In the winter, we’ve got a dozen chickens in a chicken wire pen, to keep them from pecking the greenhouse plastic and eating the spring starts. This number of chickens definitely does NOT keep our greenhouse frost-free, but the chickens are happy and warm since they are out of the winter winds. They have a bedded pack in their pen…i.e. I chuck a few handfuls of hay into their pen every morning. They like to eat the seeds, and it absorbs the excrement. In time the pack also provides some composting heat for them. In spring, the chickens get moved outside for the season, and we move the bedded pack to the compost pile. We noticed a dust problem when we had 50 meat birds in the hoophouse, but with just 12 layers it is not noticable.

26 Nov 5:32am

I also had a combined solar greenhouse (10′ X 80′) and chicken area (the end 30 of the greenhouse). I had them separated with wire mesh, and the dust from the chickens was disgusting on the salad greens in the greenhouse. I had 50 chickens (as I can remember). So maybe with fewer it might generate less chicken dust. But that was the main problem for me.


27 Nov 6:17pm

I would just like to say thank you for everyone who commented. I am in the process of designing a greenhouse to raise red worms in and am investigating ways to add warmth in the winter. Everyones comments has helped greatly


Lee Mennell
13 Jan 4:28am

I read an article in an “old” organic gardening magazine ( Rodales ) circa 1975 (I’m guessing) about a women in the Eastern United States who had a greenhouse business selling high quality herbs to restaurants. She had an attached chicken coop to provide heat and CO2. The article, if I remember rightly, discussed the difficulties in getting the system to work properly. There was some problems with the CO2, and maybe the dust. After much fiddling, balancing and I think some technology like fans and exhausts, they got it working – but it was not easy or obvious. I personally would love to find this old article. I think it is a great idea, but I remember this article had a lot of information about how it can all go wrong.

Jill Robinson
15 Jan 11:16pm

I think Lee is referring to Solviva. There’s a book still available, and the website: Very inspiring stuff!

Kira Hagen
27 Jan 9:29am

I hate to say I don’t remember where I read about this, but I’ve heard of keeping rabbit hutches in the greenhouse to warm it. I believe they were open bottom units placed over worm composting bins, so that trimmings went into the rabbits, droppings went into the compost, and the compost was reused for the plants.

Trying an aquaponics setup with water taking solar heat and providing thermal mass might work to – you’d probably need cold water fish like catfish to make it work. If you used black tanks they’d soak up sun, and you could start vining plants to cover the tanks in the spring. For that matter, you could put rabbits over catfish… Anyway, just some thoughts!

10 Feb 6:38pm

we tried the rabbit over worm compost and the emmonia made the rabbits eyes swell corsing blindness. So it might be another one to ad to the “Journal Of Failures” ,of what not to do.
Thank you all for such helpful posts.

[…] Pour nuancer cette invention ingénieuse, voir l’article In Search of the Fabled Permaculture Chicken/Greenhouse, de Rob […]