You don't want wire on the floor of a chicken tractor. No worries though, a simple wire skirt around the outside of the tractor solves the problem of a predator digging into the tractor.
I don't know how big your tractor is, or whether you're moving it by hand, or pulling it with a vehicle.
My tractor is big (8' x 16') and heavy (over 3,000 pounds) and I drag it 8 feet sideways every week to put it over fresh grass. I have 2x8 flat skids, wrapped in 60 mil PVC sheet roofing membrane.
With a heavy drag chicken tractor like this, it's crucial to wrap the two side skids in plastic, this makes the skid very slick, and also creates a rounded edge that keeps the skid from digging into the ground during the weekly pull.
It also allows me to pull in any direction, forward, backwards, or sideways.
I'm using brute force to do this with a vehicle and can afford a very wide skirt, if you're moving it manually, you'll want an easier to handle, more narrow skirt. Mine is 50 inches wide, but two feet is probably enough.
I use a cattle fence panel with half inch hardware cloth zip tied on top of it, but some members here recommend a single layer of 1 inch by 2 inch welded wire, which is thicker wire for the skirt, and will probably last longer than half inch hardware cloth since the skirt is in constant contact with the ground.
On the body of the tractor you always want to use half inch hardware cloth because raccoons can reach through larger wire and hurt your chickens without even getting inside the tractor. However on skirts you can use the wire with slightly larger openings, like the 1"x2" welded wire because there's no risk of reaching in, it's just a matter of stopping them from being able to dig under the skids.
As a tractor gets larger, it becomes almost a certainty that there will be gaps under the skids because of uneven ground, with some gaps big enough to stick your shoe under the skid.
That's where a wider skirt really shines because it extends out from the tractor so far. It either completely closes the gap because the skirt is flexible, or the predator can't fathom he's got to move away from the tractor over four feet to search for a gap.
I weight my skirt with a couple of cinder blocks on each corner, which you toss off when you move the tractor. Because my skirt is so strong, I discovered I can pull my tractor, without removing the cinder blocks.
Pulling the tractor is as simple as dropping the pull chain over the trailer hitch and pulling the tractor 8 feet. It only takes a couple of minutes to do every week.
Here you can see the a PVC wrapped flat skid, secured with screws and washers every six inches.
I keep the skirt flat with a couple of cinder blocks on the each corner. I don't even have to move them to pull the tractor.
I always keep the open end of the tractor facing south. It's a little hard to see in the photo, but I block off the east and west side open wire at the bottom of the tractor with clear plastic roofing panels, but only in the winter, the south face is never closed off, and we went down to minus 5 degrees this winter, with no problems with the chickens.
This is the North end, during the winter I seal the open wire door with a clear roofing panel.
Fresh grass floor every week.
Again, I don't know how big a tractor you've got, but perhaps there's an idea or two here that might be useful to you.
As you can see, I've gone to a lot of trouble to create this tractor, and it's a nice environment for the chickens, but I've really become a huge fan of free ranging, and my chickens are out all day, every day wandering around my yard.
However, I'm still glad I went to the trouble of creating a nice tractor for them because there are still days they have to stay in. We had a day of solid rain followed by a very snowy day this week, and they didn't go out at all those days.
I don't want them getting wet especially when it's cold. They've got food and water in the tractor, so that's a better spot for them on bad days, rather than huddled under my front porch with nothing to eat or drink, which is where they'd go, if I let them out in bad weather.
Plus it is nice to know that if a predator problem arose that I couldn't handle (I've trapped and killed three raccoons this winter near the tractor) that prevented free ranging, I could retreat them back to the predator proof tractor.
So it sounds like you've made a great choice, perhaps you can share more details of your setup and some photos.
All of us are glad to offer our experience to help you avoid any of the mistakes we've made.
