@mbushey 

There could be different ways to go about it.

If there is a covered area from the elements you can run an Ethernet cable and put another Deco.

What you could also do is wire a Deco to a EAP225-Outdoor. You can make the network name the same as the Deco, but that would prob cause issues as it will not be a real mesh network. 

I would probably go with the EAP225-Outdoor to get the best coverage and rename the network.

@Tony Thank you for the advice. I'll work on this now and see what happens.