* about 900 miners at 1300w each.
* ambient temp is 15c
* Wind direction is at west
open the windows wouldn't be enough heh
So for us idiots in the USA, that is about 2000 sq ft. Lets assume a 40 ft by 50 ft building. 40' is enough for (5) 8' aisle - (2) cold with equipment, (3) hot for exhaust air only. So we have both sides of the cold aisle with racks of equipment - so (4) rows total. With doors into the hot aisle on the inside of the building, we are going to have room for, oh, 40' of equipment more or less (rather conveniently enabling construction of the racks out of 10' unistrut. So, 160 ft of equipment rows. Say 1 miner per foot... 900 miners = 5 (800 miners) or 6 rows (960 miners). 5 rows is tall enough that you can access each row without a step-stool. 6 rows would require one. In any case, the space checks out as doable.
If you are going to build this Yahoo chicken-coop style to minimize the need for exhaust fans, your going to need about 1 square meter of vent space for every 10 miners (about 1 square foot per miner). Any smaller and you will need added cost fans that use added cost power to run. Lets presume your going to get clever and use the entire area of both ends and check that math: 960 miners = 960 sq ft. Building is 40 feet wide, times 2 (for both ends) = 80 feet. So the ventilation end-walls would need to be 12 feet high. Doable.