I have same problem My iPhone 5s and my wife's new 6s
Cannot connect to WiFi here in Florida in our house. We ARE, however, able to connect at our gated community clubhouse WiFi and at our house in Rhode Island.
My Wife's iPad [has not upgraded to 9.0.2 yet] and my Mac Book Pro Laptop CAN both connect at the house in Florida [and RI, of course].
So it is the iPhone ... I have tried resetting Modem, resetting network connections on my iPhone, done hard restart on iPhone [Home+Lock Button] .... nothing has changed .....
Doesn't Apple have automated test scripts that tests some of this stuff robotically ? or are they just as bad as every other software developer and they just wing it and hope for off shore developer & user pre-release testing to catch this stuff ....disappointing to say the least !!