My very first attempt at building a wireless thermostat involved a pair of Nordic nRF24L01+ transceivers with patch antennas. It turns out that they were unable to communicate reliably in my house, even at a range of ~15 feet: I found out through experimentation that the reliability of the transmission depends entirely to the orientation of the patch antenna: if they’re not facing each other, the range of the transceivers will drop dramatically, even if they’re within 8 feet of each other! Also, anything in the 2.4Ghz spectrum has a potential for interference and in a WiFi-rich environment, that’s a bit of an issue. Because of their low-power requirements, I didn’t expect being able to use them at long range, but they still fell short of expectations at short range.