As always...thanks for your thoughts...I'm feeling my way around this issue of whether to get an old tractor and bush hog for keeping things tidy around the farm. And of course I've gotta have a place to store the thing.
Breaking even on something like this seems very unlikely even over a ten year period so I'd like to try keep the cost down as best as I can... keeping in mind course ....I won't live forever....
Morning Keegs,
I've seen a lot of barns with dirt floors, that's fine for parking equipment out of the weather. You will get some rust on your metal things because there is no moisture control. Also hard to keep mice out, they love to chew on stuff and make a stinky mess in general. You aren't there all the time, so a barn cat won't work.
Consider this:
Remove the top soil down to clean and level dirt. Use that top soil later to build a sloping grade around the outside of the building for rain run-off.
Build the pole barn. Plan the wall height to allow for the thickness of the floor materials.
Run one or two rows of 2x10 pressure treated lumber around the inside bottom edge of the building. The top of the top row board should be above the level of the finished floor. Plan doorways carefully. Assuming an overhead door, put a section of whatever you used for poles between the inner and outer wall bottom stringers. Lag bolt this in good. This is what your overhead door will seal against. Make it level. Set it on compacted stone. Drill 3/4" holes, pin it in place with 5/8" rebar driven well into the ground every 4' between the poles framing your doorway.
Fill the inside of the building with crushed stone up to the finished outside grade level, this is maybe 8-10" of stone. For a 30'X40' building @ 9" avg. stone depth you would need 33 cu. yards of stone. Round that off to two 16 yd loads. The stone should be around $12/cu yd delivered, so $384. If the stone is running too deep, start with compacted sand, its cheaper, but put down at least 6" of stone.
Rent a vibrating plate compactor for a day. Every 2-3 inches of stone run the compactor over it until it is solid.
When you are done with the crushed stone, Lay at least two layers of 6 mil
black poly plastic over all the stone. Put a good overlap on all seams. A 200' long roll 12' wide ~$80. You can't have too many layers - within reason.
Put 3" more crushed stone on top of the plastic, compact it. For a 30'x40' building this would be ~12 cu yds, should cost about $150.
You are done. Less than $1000, solid, moisture barrier, reasonably mouse resistant.
Dave.