Yes, it is possible for Norway Rats to share a cage with Roof Rats.
Norway rats will be bigger and stronger than Roof rats of the same age and sex, but if your Norway rat is friendly and non-aggressive, it will generally be OK. Dwarf Norway rats have similar size and activity levels as Roof Rats, so are an especially good fit! As with all all introductions between strange rats, you should be careful the first time they meet in case they fight. It is usually easier to introduce rats when they are very young (like 5-8 weeks old.) If you would like to try to introduce your rat to one of our rats, please let us know because we can help!
Of special note: Roof Rats and Norway Rats are a different species and cannot make babies together! However, male rats usually won’t fight with female rats, so if you have a male or female Norway rat that cannot get along with any same sex cage mate, it is possible that he or she will accept an opposite sex Roof Rat as a friend.