If you're not in a datacenter, then sealing everything up and channeling your airflow is the best way to go. For proper cooling, you need a low ambient temp. If the miner is dumping 1000+W into your spare bedroom, then the ambient is going to skyrocket. You could throw an AC into the room to combat the increase in temp, or you could throw all the heat out the window, literally, and just keep a fresh supply of cooler air coming in.
This thread has some good ideas for properly insulating and exhausting your rigs. At that point, you don't need to worry about giant AC units, you would just need a steady stream of cool, outside air. I live in the NE USA, and even in the summer, it barely gets 25C, and hardly ever to 30C, even in the summer. In the winter, it's not uncommon to see below 0C. Fresh, cool air isn't a huge concern for me.
COLD HOT
AIR AIR
| ^
V | OUTSIDE
----FAN-----------FAN---------------
| ^ INSIDE
V |
--> ASICs -->
