Putting hardwarecloth on the bottom of a chickenwire fence is like putting an $80 case-hardened padlock on a loop of baling twine.
Any predator that ACTUALLY wants to get in to eat chickens will merely rip apart your chickenwire ABOVE the level of the hardwarecloth, and have dinner.
Those of you who have chickenwire and have not had a problem yet -- need to be aware of that last word there, YET. Lack of losses with chickenwire simply means no predator happens to have TESTED your run fence yet. When they do, we all pretty much know what will happen.
Unless you are comfortable using Lady Luck as your predatorproofing strategy, I strongly recommend ditching the chickenwire and using something stronger, like heavy gauge good quality welded wire with holes no larger than 2x4".
Good luck, have fun,
Pat