I'm getting a used trailer house for guests and storage on my farm.
From past experience I found that trailer houses attract mice. Once
they get into the insulation under the floor, the damage begins. I
considered covering the entire underside of the trailer with sheet
steel, but it would be very costly, and probably difficult to install
too. Someone said they knew someone who used window screen and said it
worked, but that they had to regularly check for loose edges because
mice and other critters would loosen it. I got to thinking about that
1/4" hardware cloth. That stuff is comparable in price to window
screen, but much more durable. Probably easier to attach too, because
it can be nailed with roofing nails, not just staples, and it can be
folded at the edges to go under the skirting flange along the edges of
the trailer. Plus, it can be screwed in place in spots where it might
need to be removed, such as by pipes. And it can be wired together if
there is no solid wood in spots, along seams. Plus, I'm sure it will
last much longer than screen.

The question is whether mice can get thru the 1/4" holes. I know they
can manage to get into small holes, but that size seems to be a little
too small. Has anyone tried this? Any other suggestions?

Thanks