After watching my poor kitties always crying at me when i was on the deck, I decided I was going to build a cage around the deck and create them a catio! (cat patio). This isn't exact instructions but a 'what i did' in case you are interested in a different way about adapting one to your deck.

Here's where i got my rough building plans from (that i adapted to my deck, as i didnt build a 'box' persay as they instruct:
http://myoutdoorplans.com/animals/fre...