Most chicken coops are made of wood, and all wood eventually rots. You can deal with this fact in a number of ways:
- Build with wood that’s infused with pesticides (pressure-treated “PT”)
- Use a naturally rot-resistant wood (like cedar, redwood, or tropical hardwoods)
- Choose a softwood (like Douglas-fir, hemlock, or pine) and apply a sealer
- Use a composite material instead of wood
Many factors will weigh into your choice, but I’ll deal with the two biggies: toxicity and cost.
Toxicity
Treating lumber with a non-toxic preservative
Anything put into or onto wood may find its way into your chickens, then into you. This makes PT generally a poor choice. The EPA advises against using any kind of PT “in circumstances where the preservative may become a component of food, animal feed, or beehives.” (One exception to this may be YellaWood®, available in the South. Its manufacturer claims that it is an environmentally preferable product because of the special way it’s treated. I don’t have personal experience with it to give an opinion.)
As for sealers, choose carefully to avoid toxic ingredients. Personally, I like the products from TimberPro Coatings. Ecohaus in the Pacific Northwest also offers some safe options for exterior use, including the brand Osmo. Finally, using naturally rot-resistant woods gets you around the toxicity problem altogether, but leads to the second issue. . .
Cost
Let’s start with cedar. It’s pricey, and while praised for its rot-resistance, this characteristic is true more of the heartwood than the sapwood. Two local lumber stores told me that most available cedar comes from second-generation forests and lacks the longevity of old-growth heartwood. Both steered me away from it, saying that you’d have to seal it, and if you’re sealing it anyway, you might as well use cheaper softwood. Other costly options include the composite material used for decks and FSC-certified tropical hardwoods, both of which are more expensive than cedar, yet can last unsealed for decades.
The best choice?
I’m not sure. But I can share some principles:
- Mix materials based on how exposed they’ll be in your finished product, investing in longer-lasting materials where it pays to do so.
- Remember that once you attach hardware cloth to the wood, you will likely never get the chance to seal it properly again.
- Use a non-toxic preservative such as Internal Wood Stabilizer from TimberPro UV on any unsealed softwoods.
- 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.
- Remember that the best wood may be what you can reclaim from another project. Make sure it is free of toxic paint, seal it up, and you’re good to go.
- 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!
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.
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.
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.
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.