Quote Originally Posted by cobweb2000 View Post
I don't think its overkill and I'm sure they would enjoy all the space, BUT I had my very first trio in an old ferret cage that had 1" x 1" bar spacing so I covered it with 1/2" x 1/2" hardware cloth and they chewed a hole in the cloth in under 2 days. There are some people on my rat forum that are breeding them for pets who keep them in wire cages made of powder coated metal and 1" x 1/2" bar spacing and apparently that is fine for the largest adults but she had juvenilles and smaller adult females manage to find their way out. I have 3 40gal wide and 2 50gal long aquariums for them with metal mesh screens and so far have managed to avoid any escapes. The aquariums are also large enough to provides wheels, boxes, tubes, shelves for more floor space and hammocks so they have lots of stuff to do.

I'm glad you are looking into giving them a lot of space. I realize racks are a necessity but it still makes me sad to see asf's/mice/rats kept in them with nothing to do.
For ASF's
I've never had them escape 1/2" hardware, or chew through it, I find the 1/4" is a lot flimsier and seems easier for them to chew through.

For norway rats
These rats live in burrows, while they can be extensive, they are small holes in the ground.

I will be the first to admit I was constantly torn between offering large cages or just racks. Over the past couple of years, I have realized that the rats really don't care if they are in a one level rack tub, or a cage. In fact, when I have offered large cages with a bunch of hammocks, they are hard to keep clean, and most of the rats hang out on the bottom anyways!

The rats aren't super bored, they have each other in the wild, they raise litters in the wild, they mate and breed. They are quite accustomed to living without toys and ramps and hammocks.

The only thing I don't like about racks is I can't offer a wheel, and I can't spare huge amounts of floor space with a rack to let them run around in. I have a lot of girls that use wheels when they can.