Building a Recycled Farm Structure
We recently had a need for a new hen house for our free range laying chickens.
The coop we had been using for the last two years could sleep about 50 hens. It had integrated nest boxes and a slat floor that allowed manure to fall through. And most importantly, it was on skids so that it could be pulled by a tractor when moving the pastured chickens to new ground.
Our new hen house needed to sleep around 300 chickens at full capacity. It also needed to be portable so that we could continue our pasture rotation system. And most importantly, we wanted it to be built mostly from recycled materials.
The resulting building ended up being much more versatile than we were originally hoping for. Not only is the building attractive, it can easily be scaled up or down depending on your needs. We plan on using similar construction techniques and design in the near future for a hog shelter, cattle shelter, firewood shed, and storage shed.
This project started with a pile of pallets I've been collecting for some time now. My original plan was to use the pallets as structural components that would be sheathed with plywood and painted. This is a very common technique used by folks all over the world for creating cheap structures. However, once I started looking at my stash, I realized I could create a better structure without having to purchase plywood and paint. By deconstructing some of the pallets, I could use the planks to fill in the gaps on other pallets, creating a board and batten effect.
Before we go on, a word of caution about pallets. Pallets are usually treated to ensure they do not contain insects. When determining which pallets to use for your project, look for an IPPC stamp. There will be a few numbers and letters on this stamp... you're looking for "HT" or "MB." HT stands for Heat Treated, indicating the pallet is perfectly safe to use. MB stands for Methyl Bromide, a chemical you don't want o mess with! If you don't see any markings, I recommend not using the pallet, as you don't know what chemicals where used on it.
After verifying the safety of my pallets, I pulled out a reciprocating saw with a wood/metal blade and got to work. Each pallet took about ten minutes to deconstruct and resulted in some great recycled wood. Using 16d nails, I attached the freshly liberated boards to other pallets, creating a solid wall.
The load bearing walls are 16 feet long. That's a total of four pallets wide. Once I had the pallets constructed, I tied them together with a 4x4 footer and a 2x4 header. The pallets are connected to the footer using 3" long 1/4" galvanized lag bolts. The header is attached with 16d nails and 3" screws.
The shorter walls are 12 feet long and follow similar construction techniques as the longer walls. The walls are connected together with multiple Simpson construction ties at both the top and bottom. Since this building will be portable, I went a little overboard with the construction of the walls.
Once the walls were up and secure, it was time to start building the roof. I chose to construct simple trusses in my shop rather than frame the roof in place. This made the process very easy. Before starting this process, I decided on corrugated metal roofing. With this in mind, I knew the trusses wouldn't be supporting a significant amount of weight and could be built a little lighter than what might be used on a house or pole barn. The trusses are spaced four feet apart. The legs of each truss are just under eight feet long and have two support cross members: one at the peak and one about a foot and a half down. It was important that there was plenty of head room so that people could easily walk through the building; I'm 6'3" and can comfortably walk from end to end without much crouching.
With the trusses in place, we just need to add horizontal battens and the metal panels. The horizontal battens are spaced two feet apart and screwed into each truss. The battens were ripped from 2x4's and are a bit over an inch thick.
Metal corrugated roofing was chosen for two reasons. I've used this material extensively for other projects and had a bit lying around. It's also the cheapest durable material I've found for roofing. For a few extra dollars per panel, you can step up to a hard foam panel that will last longer and add a bit of insulation to the roof. When installing the roofing, use metal roofing screws... they contain a small neoprene washer that ensures a leak-free installation.
Depending on your intended use of the building, you may not want to use metal roofing. If there will be excessive build up of manure within the structure with minimal air flow, the ammonia from the manure will slowly eat away at the roof. While manure will build up in our henhouse, we have extensive ventilation in the building and the building is moved frequently, so ammonia was not a concern.
With the building complete, you can decide how to configure the inside. Since this is a hen house, I've added roosts to one side of the building. The other side has been left open to allow room for feeders. The open area also provides our ducks a spot to sleep (although they almost always prefer to sleep under the stars).
In the future, I plan on adding gutters that will divert the rain water to 55 gallon barrels. This water will be used as drinking water for the chickens. I'm also thinking of building some removable walls to fill the triangle voids between the walls and the roof for when the weather gets really cold.
Have ideas on how to improve upon the design? Or other uses? Please share in the comments below!