How can I prevent animals from getting behind the siding on my house?
I am having an older home resided. At this point there is no strapping between the sheathing and siding, but I want that added to help with moisture control. What is the best way to prevent rodents from getting into that space and using it as a highway?
Siding needs vertical strapping to create an air space to allow moisture to escape and water to drain, read more here -
How to Install Siding so Walls Can Dry
That’s a valid concern you have, and yes, you should have some sort of protection that allows water to flow out the bottom and air to flow up so humidity can escape at the top. There are a few products intended exactly for that purpose, one we tried and were very happy with is called Cor-A-Vent. You can also do it with aluminum vents from soffits or screens as well. If you're concerned with rodents then perhaps you've already had encounters, so this page may offer you some valuable tips as well -
How to Remove Pests and Rodents from Homes Humanely