OK, based on the many responses (and thanks for those), I guess I didn't fully explain the setup.
We have fenced off the yard on the north side of our house into a dog run. It is about 45' x 25', and has planter boxes with trees and shrubs, dog toys, and a couple of automatic watering dishes. When we are at home, the pups (and our ten y.o. mutt) are in the house or or the rest of the yard (1/3 acre) with us (me, wife and kiddies). They are never in the run all night. The pups spend the night in our bedroom in a crate, the mutt has one of those big dog beds next to our bed. FYI, the male pup snores, the mutt farts. I cut a doggie door into the garage so that on rainy days (Sacramento, CA, it doesn't snow here) they would have some place to get in out of the rain. I have fenced off about a 6'x6' area inside the garage, and it has a wooden pallet to get them off the concrete and some of those fleece dog blankets. Also, I had an electrician put in overhead lights that we can leave on for them. When I die, I want to come back as MY dog, because they have it pretty good. The neighbors on either side of us and in back tell us that they are very quiet, probably because they have each other. I think that one of them clawed the drywall in the garage because I was trying to sneak in and do some work without bringing them in. They heard me inside, clawed off some paper, then found that fun, dusty stuff under the paper. Now they have a hole in the wall and it is something new and interesting.
So I appreciate the tips on sheet aluminum and Hardiboard, and will head to HD or Lowes later today.
Thanks, Dave