[Post updated Dec. 2017] Most chicken coops are made of wood, and all wood eventually rots. Our coop designs feature overhanging roofs to protect the structures and their occupants from rain. But your coop will still get wet and be exposed to humidity, insects, and UV light. To protect the wood from the ravages of being outdoors you have a few options:
- Build with wood that’s infused with pesticides (pressure-treated)
- Use a naturally rot-resistant wood (like cedar, redwood, or tropical hardwoods)
- Choose a softwood (like Douglas fir, hemlock, spruce, or pine) and apply a nontoxic sealer or treatment
- Choose a plywood designed for exterior use and stain or paint it
In this post, I’ll go through each of these options, weighing the pros and cons. I’ll start with my least favorite and end with my preferred approaches. For a quick overview of our 10 tips and takeaways click here.
Pressure-Treated Lumber
Anything that’s put into or onto wood may find its way into your chickens, then into you. So let’s first consider the reasons to avoid using pressure-treated (PT) lumber.
Cons
- PT can leach copper and other potentially harmful stuff into the soil where your chickens will be. I say “potentially” because the preservatives currently used in PT (alkaline copper quat, or ACQ) is said to be safer than the stuff they used to use (chromated copper arsenate, or CCA) in that it doesn’t contain arsenic. That said, the EPA still advises against using any kind of PT where the lumber contacts soil, crops, or livestock in an organic production area.
- PT requires more expensive fasteners designed to be used with ACQ, such as stainless steel or hot-dipped galvanized screws and nails. (Regular galvanized fasteners aren’t designed for the increased level of corrosion that comes from contact with copper. Read more here.)
Pros
- PT is softwood lumber injected with chemicals that render it pest-proof, maintenance free, and water resistant for many years.
- It may be cheaper than other wood types.
- Where it actually makes the most sense to use on a chicken coop is at the bottom of the frame, yet that is precisely where your hens will be scratching around and rubbing their beaks. Leaching of toxins can be minimized by priming and painting the lumber.
- If you prepare it right, treat cut edges, are careful in collecting sawdust, and use it appropriately, PT might make sense for you, especially if you’re in an unusually humid or termite-prone area.
Cedar, Redwood, and Tropical Hardwoods
If you’re wary of pressure-treated lumber, there are wood species that last a long time thanks to natural preservatives inherent in them. Cedar is the most widely available, though in certain regions redwood and tropical hardwoods are easier to come by.
Pros
- Using naturally rot-resistant woods, such as cedar, redwood, and tropical hardwoods gets you around the toxicity problem altogether. It is possible to use these products without sealants saving you time.
Cons
- Because of the demand for these woods, they can be pricey.
- Rot-resistance can vary from tree to tree. Also, while cedar is praised for its rot-resistance, this characteristic is true more of the heartwood than the sapwood. Most available cedar comes from second-generation forests and lacks the longevity of old-growth heartwood. You would have to seal it in this case, and if you’re sealing it anyway, you might as well use cheaper softwood.
- Sourcing heartwood cedar, redwood, and FSC-certified tropical hardwoods can be time consuming. You may be in for an expedition when looking for more specialized lumber products.
- Some people have concerns about the effects of the oil in the cedar on chickens. There is a lively, well-informed discussion in the comments below to help you learn more.
Softwood — Stained, Painted, or Preserved
This is my preferred option for lumber to frame up a chicken coop. Using standard softwood lumber (fir, spruce, hemlock, or pine) and sealing or treating it with a nontoxic paint, stain, sealer, or preservative takes a little more time, but it gets around the potential toxicity issue of pressure-treated lumber and is usually more affordable than a naturally rot-resistant option.

Pros
- By sealing/treating lumber with a nontoxic product, you can transform less expensive, off-the-shelf lumber into a long-lasting, weather resistant building material.
- My preference for preserving softwoods is TimberPro UV’s Internal Wood Stabilizer (IWS). It brushes on like water and reacts with the wood to harden and densify it. One application (2–3 coats) is all it takes. Wood treated with IWS stays bright for a year or two, then fades to a silver, naturally weathered patina. As of this post update in late 2017, our coop has lasted nearly a decade in rainy Portland, Oregon, where it gets soaked in the winter and baked in the summer. It has shown no signs of rot. Unlike with PT, standard fasteners still work with wood treated with IWS.
- If you prefer a splash of color, it’s possible to paint over the top of IWS as long as you wait the proper time to let it cure (at least 3 weeks — see manufacturer’s site). The manufacturer does not recommend staining over IWS, as the IWS seals the wood too well, preventing the stain from soaking in. You may, however, do a combo, staining the outward-facing sides of the boards while using IWS on the inner faces. Give extra attention to the bottom of the frame (the sole plate), all the cut ends, and any horizontal surfaces. Those are the areas that will be most exposed to moisture.
- Many coop owners prefer simply priming and painting and skipping the IWS application. Paint will protect the outer surface of the wood from the elements. But consider that wherever a nail, screw, or staple penetrates the wood, water can get in. So once you’ve attached hardware cloth to your frame, you won’t be able to retouch the paint — neatly, anyway. Choose paint and sealers carefully to avoid toxic ingredients.
- As for stains, I like the offerings from TimberPro UV. Osmo brand stains are really nice too. For more about stains and sealants, see our Buyer’s Guide.
Cons
- It takes time to apply any of the above treatments.
- If you plan on painting over IWS, you have to wait three weeks after you prime and paint.
- Nothing in IWS repels insects such as termites. But it’s worth remembering that chickens are voracious eaters of termites, and they forage down low, right where termites would be of concern.
- You can’t easily repaint lumber once hardware cloth has been applied.
Grades of lumber
A note about grades of lumber. Grades indicate relative appearance and strength. The higher the grade (smaller #), the better. Lumber stamped “#2 or better” or “standard & better” is the way to go.
Unseasoned or “green” lumber has a high moisture content, which makes it heavier, and water in the wood creates a poor surface for products like paint and stain to properly bond. Instead, look for two-by-fours that have been kiln-dried. The drier wood will also soak up more of any stain or treatment you apply.
Plywood options
Some portion of your henhouse may require plywood. As with dimensional lumber, there are different options depending what you need and how much you’re willing to spend:
- Oriented Strand Board (OSB) is the cheapest form of plywood. OSB is engineered by using adhesive and compressing layers of wood strands together to form a solid sheet. OSB that has been sealed with primer and paint is a reasonable choice for use inside the henhouse. Seal it well or cover with linoleum if you’re going to use it for the interior floor. Do not use OSB on exterior applications where it will come into regular contact with moisture. It will swell and fall apart.
- Keep in mind that regular exterior plywood is also not meant for use as siding. The glues in exterior plywood are formulated to stand up to temporary moisture, but they cannot withstand sustained exposure to the elements. If you are going to use regular plywood on the outside of the coop, protect it well with a primer and at least two coats of quality exterior latex paint or a sealer. Inside the henhouse, it’s just fine to use.
- Even better for siding is to choose a product intended for that use, such as T1-11. This typically has a textured surface on the outer face (rather than sanded or bare) that won’t split or blister as easily and holds up better to the elements.
- A truly rugged option inside and out is marine-grade plywood. This is designed with water-resistant adhesives and more durable wood. Marine-grade plywood is significantly more expensive and harder to find than standard, exterior grade plywood.
- Instead of marine-grade plywood, I prefer medium density overlay panels (MDO). Their smooth, resin-soaked veneers make them ideal for outdoor applications, and their smooth finish accepts paint very well. Importantly, it is cheaper than marine-grade plywood and can be used similarly.
Remember to paint all outer faces and edges of the walls and doors as well as the inner faces of any doors. You can paint the inside walls and floor of your coop too, if you want. I like white for this, and the glossier and more durable the finish the better.
10 tips and takeaways. . .
- For framing and roofing use standard softwoods and apply a nontoxic paint, stain, or preservative such as TimberPro UV’s Internal Wood Stabilizer (IWS).
- If you prefer more color on your coop or are concerned about greying wood, wait three weeks after the IWS application and prime and paint your lumber.
- Sand, stain, prime/paint all plywood.
- For siding, use a product intended for use as siding. Avoid using OSB as siding and consider medium density overlay (MDO) panels instead of regular plywood.
- Remember that the best wood may be what you can reclaim from another project. Make sure it is free of lead/toxic paint, seal it up, and you’re good to go.
- For health and environmental concerns, steer clear of pressure-treated lumber unless you live in a very humid environment or have termites. Even then, use it only where needed.
- Remember that once you attach hardware cloth to your chicken coop, you will likely never get the chance to paint or seal the frame properly again.
- Build so that you can replace pieces without having to dismantle the whole coop. This way, a rotten board every few years isn’t such a big deal.
- Mix materials based on how exposed they’ll be in your finished product, investing in longer-lasting materials where it pays to do so.
- The perfect is the enemy of the good. Don’t let your search for the ideal materials or design get in the way of building something. After all, it’s just a chicken coop!
What has worked for you (or not) in your coops and outdoor wood structures? Please leave a comment below. And visit TheGardenCoop.com to learn more about our detailed chicken coop and run plans and hardware kits.
59 thoughts on “Which wood is best for a chicken coop?”
What would you recommend that is just as good the TimberPro UV IWS? I am unable to get that particular kind in my area.
Hi Allaina. The IWS happens to be the only product of its kind that I know of. Not sure where you are, but you can mail order it in the U.S. at least. As you can see in the coop profiles on our blog, people use a variety of products. I’ve heard good things about Osmo stains. And any exterior paint or sealer should work well to protect the wood from the outside.
Is it safe to build a coop using Eastern White Cedar?
From what I’ve read, you don’t want to use eastern white cedar as bedding. Should be fine to use as lumber in a well ventilated coop.
Hello, we recently just had a coop/run built for us. The inside was painted white, but the builder only painted one coat and I’m not sure if it was primer or paint. I can still see the grains in the plywood and the barcode stickers. We currently have baby chicks in a brooder box in our coop now. I didn’t add more coats of paint before we got them because I was worried about them breathing in the paint fumes. We just didn’t have enough time to wait for the fumes to go away. Now I’m thinking I will have to wait till next summer to paint more coats in the coop portion so they can be outside while it airs out – we live in OR.Is there a certain amount of time that you recommend letting the paint air out before letting the chickens back in? Ideally, I would like to paint it now before I let them out of the brooder box, but I don’t know where I would put them in the meantime. My husband is adamant about no chickens in the garage because last time we had our brooder box in there, chicken dust got EVERYWHERE. Any tips? Thoughts? TIA.
Ashley, I’d go with a zero- or low-VOC exterior latex paint, then wait to put the chickens back in until the product has cured and the odor has faded. 24 hours after the final coat might be enough, maybe 48. There should be some guidelines on the can. You’re basically waiting for the solvents to evaporate. You could open all doors, windows, and vents and put a box fan on it to speed things along.
I won’t allow chicks in my garage again either, because of the dust. 🙂 But if you had to for a short time, you could use some old bedsheets to create a curtain around the brooder for the day or two they have to be in there. Maybe put a box fan in the window aimed outward to pull any dust through before it settles. Or just wait until they are more feathered and producing less dust. Better to take care of the painting now than wait until they’ve lived in the coop. It’ll be a lot harder at that point to get it as clean as it needs to be for painting. Hope this helps.
Thanks for the good information,
I am just getting started and every information is helpful
What about these new plastic or pvc coops? Like Omlet. Are those a good option?
Omlets have been around a while. I haven’t heard anything bad about them. Some of our customers build a walk-in coop or larger run then either attach the Omlet coop to that or set it within the run. Here’s an example of an Eglu attached to a Garden Coop.
Hi, thank you for providing very helpful information. I’m thinking of using the T1-11 plywood for sidings. Do I need to sand it before applying stain, sealer and paint? To further protect the sidings, I’m considering placing tin over the plywood. I live in Maryland so it can get fairly cold here. I know tin alone is a concern for condensation but do I need to worry if I have the tin on top of the plywood. Would you recommend placing a lining between the plywood and tin that keeps moisture out? The coop will be under lots of pine trees providing ample shade. I look forward to your recommendation.
Josh, you do not have to sand T1-11 before painting or staining. The siding is meant to be the outer layer of protection, so I’m not sure why you would need to add tin over that (on a vertical application, anyway). But if you do, maybe treat it like a roof and add a layer of roofing felt between the tin and the plywood siding.
I was going to build a run and use treated lumber on the ground and 2x4s of western red cedar every 3 feet vertically and fix the hardwire cloth to that with a simple roof. The coop is normal lumber. Is this in issue to have 20 posts that are Western Red Cedar and have them only in the run?
Billy, I don’t see a problem with that.
Have a quick question! We live on a farm and ranch so we have plenty of railroad ties around!! Can we use these for the base of our chicken run?
I don’t know, Jada. My guess is that the fumes would be the worst part about the creosote, and those fumes wouldn’t build up in an airy run. The concentration has probably also dissipated over the years. Not sure if you’ll get a more definite answer there, but you might also search the forums at BackyardChickens.com.
Hello!
Not sure how quick responses are but my husband and I are planning on building a coop and just got materials today. However, we were going to use OSB as the main siding. After reading this, I’m having second thoughts. We were planning on doing two coats of primer and two top coats. We hope to have the coop long term so now I’m wondering if we should instead get medium density overlay panels. Is it truly worth it?
Elicia, I’ve seen people use OSB for siding and do as you’re saying, coat it up really well. I can’t promise how long that will last. It’s main enemy is going to be the sun causing the face to expand and contract (blistering whatever you coat it with), so if your coop is in full shade, it might stand a better chance. MDO panels is meant for outdoor applications. Whether the cost is worth it is a calculation you’ll have to make. If you don’t mind redoing the siding some years from now, then maybe try your first option since you already have the materials. But if you’re investing time into it now and want it to last, I’d say MDO or plywood T1-11 is worth it.
My head is spinning with siding options. I was initially going to do 1/2” treated plywood then cut dog eared fence pickets shiplap style over that for siding. Maybe overkill. I live in Wisconsin. I have seen those that just do 2×6’s for siding and prime and paint and just go from there. Any advice appreciated.
Rachel, regular (or treated) plywood will work as a backing to the fence boards, like you’re describing. Or you could just use the fence boards and butt them together. 1x4s or 1x6s could work too. 2x6s may be too much heft. Your chickens won’t mind whatever you do, so I’d say go with what you think looks best.
Hello! Would sassafras wood be okay to use for the chicken coop?
Heather, I’ve never worked with that wood, but based on how it’s described here, I’d think it would work well for your coop.
I have PT pine that I have had for a couple of years (stacked and semi-covered from elements). Would I still need to use stabilizer?
Gail, the Internal Wood Stabilizer product we mention does essentially what the preservatives in pressure-treated wood do, but through a different chemistry. So you would not need to retreat the PT you have. You could paint or seal it though, that’s up to you.
I have a cedar tree that sheds debris during the winter in the area of where I plan to build a coop for my new chickens, is this going to be a problem?
Jason, that will not be a problem for your chickens.
We are make or coop out of pine trees is that good or bad
Pine is just fine!
Hi, Thanks for this question and all the answers.
I wanted to check about WESTERN RED CEDAR and using it as a chicken grazing frame. I don’t want to use chicken wire or other metals as the top of the grazing frame due to heavy metals and I wondered if using western red cedar in thin strips nailed to the western red cedar base would be okay?
The grazing frame would be kept outdoors but it would be in the sun all day (hot Australian sun) and watered daily.
Do you know if the hot sun and the daily watering could potentially cause leaching of any toxic oils (or anything else) into the seedlings growing up underneath the thin strips of cedar inside the grazing frame?
I want to use cedar for its rot resistance and prefer not to use other wood that I have to coat in more toxic water sealers….
Thanks for your help.
Tasch, thanks for your questions. My understanding of WRC is that you want to avoid handling or inhaling the fine dust created when sanding or sawing it. I have not heard of its oils having a negative impact on soil or plants. To the contrary, here’s a research review that talks about WRC being beneficial when used as a mulch. As for the galvanized coating (zinc) on hardware cloth, screws, nails, etc. possibly affecting your soil, here’s an article that speaks more to that. Hope this helps.
Thank you so much for your help and the links you shared with me as well. They’re all very helpful and informative!
Much appreciated 🙂
Tasch
HI
My husband is going to make me a hen house. He is joinery manufacturer.
He says it would be easier for him to make it out of Moisture Resistant MDF and then paint it. He feels that there would be less crevices for redmite to hide.
The hen house would be under cover from the elements.
Would this wood be okay for my hens ?
My understanding is that sealing MDF greatly reduces any potential offgassing of formaldehyde. You should design your henhouse to have plenty of ventilation anyway to avoid the buildup of moisture and ammonia (from exhalation and droppings), so if you do this, I wouldn’t foresee a health problem with using that wood. Make sure to seal the henhouse floor especially well as it will be exposed to the most moisture. Hope this helps.
I once built a coop in the inside corner of my garage, and from there the chickens had a door to the outside run. In my garage we had a floor drain. This was perfect for washing out the coop and directing it down the drain. To effectively wash out the coop I decided to use a pond liner I had reclaimed from a pond project a few years back, 12×20′. I lined the floor and half way up 3 of the walls. This made clean up a snap and the material was such a gauge the it withstood a vigorous shoveling as well.
We are building a chicken cope and want to make it as cheap as possible, would old fence palings be okay to use?
Kayla, if the wood looks free from rot and insect damage, it should be fine to use. If it was treated at some point, chances are the worst of that has leached out by now.
Is red wood a good choice?
Carmelae, if it is reasonably priced in your area or if you can find it reclaimed, redwood is a beautiful, naturally rot-resistant option. I’ve seen people, mostly in California, use it for the siding on their hen houses when building our chicken coop designs. You can see a few examples here, here, here, here, and here.
As for lumber I thought the cheapest is yellow pine. I know pressure treated wood is ok outside but it does have arsenic in it to deter bugs. So I don’t know about that. I built my chicken tractors out of the wood that comes off of the log splitters that Attwoods ranch and farm store sells. They just throw the crates away. Check them out see what they are tossing. Its first come first serve, I understand, but I got enough to make 9 chicken tractors in one day!
Thanks for the tip, Joseph. Pressure-treated wood no longer contains arsenic. But since the newer preservative (ACQ) is higher in copper, you need to use more corrosion-resistant fasteners.
If I may add, heat treated Pallets have the symbol HT printed on them. These are chemical free and ‘food-safe’ so they would be perfect.
Great tip, Robert. Thank you!
I have not raised chickens for years. We always used straw for bedding. Are there any issues with Hemlock for building a chicken coop?
No issues with hemlock, Joan. Hope you enjoy keeping chickens again!
I have really gotten the run around form Home Depot and have no idea what to use. They sold me Pressure Treated wood and then said not to use it for a coop because it warps and twist for up to 6 months. Now I’m back to step 1. Should I just by regular 2x4s for framing. Do I seal them before using them? Is 1/2 inch plywood ok for the floors and 1/4″ laminate for the walls? I was using tin for the roof and someone said to put up plywood and then tin. If so, 1/2″ or 1/4″.
I am 61, disabled, and love chickens. If I could start over I would have given up my dream of chicken. If I could rehome my chickens I also would give up. This is affecting my health.
Jisele, I typically recommend using regular framing lumber and preserving it with TimberPro UV’s non-toxic Internal Wood Stabilizer. It’s great stuff and very pleasant to work with. But I’ve also had several customers use pressure treated wood for their coops without the warping issues you mentioned, so if that’s the best option for you (considering cost and availability), I wouldn’t rule it out. You do need to take some precautions when handling it and cutting it, and you want to treat any cut ends with a sealer.
I would use a 1/2″ or thicker plywood for the floors, unless people will be walking on them too, in which case go with 3/4″ or thicker. For the siding, I would use 1/2″ or thicker plywood siding, fence boards (new or recycled), or any other product intended as siding. For the roof, if you have a well ventilated design like The Garden Coop, you can attach a tin roof directly to 2×2 or 2×4 purlins — no need for plywood underneath. The recommendation you received to use plywood probably had something to do with limiting condensation under a thin-material roof, but that’s more critical in a sealed structure where humidity can build up. You want your chicken coop to be well ventilated. Just make sure to install your coop roof according to the manufacturer’s instructions so that you have the right amount of support beneath and to minimize the chance for leaks at the attachment points.
Hope this helps.
With all I have read about cedar I will not use it at all. If the toxic part is released in shavings how would it not be released when they peck the wood? I live in the southern part of the United States. It’s nothing for us to get in the upper 90s and even over 100 degrees I’ve put to much time and effort into my girls to line their home with a potential toxin. I’d much rather replace messed up boards from time to time.
Tommie, thanks for commenting. Make sure your coop has great ventilation in that climate — that’s the most important part!
Any cedar wood will release fumes when heated or cut (such as using cedar bedding and cedar coops in summer temperatures). The fresher cut and younger wood releases more, but even well-aged cedar has toxic components to it.
It’s always safer not to use cedar if you can help it, especially cedar bedding and fresh timber.
A good rule of thumb for any bird or reptile owner (even for chickens) is if the product you are using has a odor to it, don’t use it, even if the odor is natural like cedar wood.
I ordered Timber Pro Internal Wood Stabilizer last week at the same time that we purchased all of our other supplies for our coop. Unfortunately, there was a 5 day delivery on the Wood Stabilizer. We had such beautiful spring weather here over the weekend I just couldn’t wait to start assembling the coop. It went faster than I thought and I’ve completely finished the framing and the rafters. I skipped attaching the roof because I wanted to apply the wood sealant before I did that. I did skip ahead and go ahead and frame out the hen house and the door. The Timber Pro product is scheduled to arrive tomorrow. Am I going to lose the effectiveness of the Internal Wood Stabilizer by applying it at this stage and not being able to saturate all sides of the boards evenly? Tips on how to make the best of the situation? Also, I’ve been told to wait 30 days after applying the Internal Wood Stabilizer before staining the wood. Won’t that be difficult once the hardware cloth is installed? Suggestions on ways to do that? Or would it be best to leave the wood bare at that point? Thanks for your help. We love the coop design and are looking forward to completing it.
Keith, lots to cover. I’ll reply directly via email.
In the spring of 2011 my husband & I remodeled an old cedar sauna into a very nice chicken coop with windows that opened on the north & south sides. By fall the chicks had grown to 10 healthy egg-laying chickens that free-ranged in our yard until the snow came. We had the windows open enough to provide ventilation and the old building itself was not air tight. There was never an ammonia smell and they all seemed o.k. The roosting spots in demand were the ones by the 5′ & the other 2′ window. In fact, they would almost sit on top of each other in order to fit. As the winter went on, they became more and more tattered looking. It was about March when they all quit laying. This was not a molt as we made sure they always had at least 14 – 15 hour of light. They never started laying again. They did start looking better during the course of the summer and we let them go through a good molt as the days got shorter again in the fall. Much to our dismay, there seemed to be plenty of evidence that pointed to cedar toxicity. Reluctantly we lined the coop with poly & sheeted over it with 1/4″ painted OSB. The girls started roosting on the lower roosts right away. I thought they just wanted to look outside but it must have been their attempt to get better air. We put down pine shavings and they were back up by the windows. My theory is that they have become extra sensitive because most everyone in the area use the pine shavings for bedding. Only one chicken began laying again. Since adding the poly the ammonia has been more evident … will have to do something to improve the ventilation. Because of this experience, I am convinced that cedar at any age or in any form is toxic.
Thanks for your comment, Janice.
Western red cedar is also a problem. Look at the OSHA guidelines at the link below. Scroll down to the final paragraph under “Health Effects”. There may be irritating oils in eastern red cedar which are not discussed in these guidelines, but the guidelines indicate that western red cedar is particularly high in a certain one, plicatic acid, which is most irritating to the lungs. Also note that the guidelines indicate that heavy exposure to sawdust from any kind of wood can be a problem. For all types of wood, it is the degree of exposure that is important. If your chickens free range most of the day, it won’t kill them to spend the night in a well ventilated coop with cedar shavings, if that’s your only option. If they are confined 24/7, use something else.
http://ohioline.osu.edu/aex-fact/0595_1.html
Came here to check on the cedar coop issue. Just wanted to add that I saw recently that it’s the oils from EASTERN red cedar (aka aromatic cedar), not WESTERN red cedar, that is harmful when inhaled. This is supposed to be true for both animals and people. Just an FYI.
We have a chicken rescue. A new government study found that it was the aromatic oils not the dust that lead to tumors, kidney problems and liver problems in both adult and young chicks. Because of this, I would suggest no fresh cut cedar at all in your coops.
Alana, thank you for your comment. I agree the phenols are the issue, but it’s the grinding or shaving of cedar into bedding (or into sawdust, for people who work in mills) that releases those oils in potentially harmful quantities. The studies I’ve seen generally caution against 1) cedar bedding and 2) the use of concentrated cedarwood oils (used as a pesticide) around small animals.
Yup, it’s only cedar bedding (shavings or sawdust) that are potentially problematic for chickens. All of the animal studies showing that cedar causes illness were done with cedar bedding, not cedar cages. It’s the ground up wood that releases the compounds. Ground up wood (wood dust) can also be directly inhaled into the lungs of the animal, carrying all those irritating compounds with it. A board of cedar wood doesn’t release enough of the irritants as gases to cause illness.
I’ve read on other sites that cedar could be toxic to chickens. If so, it’s not a good choice for a coop or run. Do you know anything about this?
Ginger, the potential problem with cedar is with cedar shavings, not with the whole wood. Many people recommend not using cedar shavings with young chickens because the ground-up wood releases phenols (aromatic oils) into the air that, if allowed to build up in a poorly ventilated space, can damage their sensitive respiratory systems. This is not the case with whole wood. So cedar is perfectly acceptable to use to build your coop. Your question is a good reminder, though, that chickens need a well ventilated space to prevent build-up of ammonia, excessive moisture, mold, and anything else that might stress their lungs.