Height from ground for Fresh Air Intake
 

I need to install a fresh air intake to the basement, and wondering what sort of clearance I should have from the ground. I've got a bit over 2 feet between ground level and the subfloor. I'm in Minnesota, so I ask because of the potential for snow to block the intake.

12" above normal snow fall accumulation level.

So do I then need to put a gooseneck in my line? To do 12" above snow level on a straight shot I would have to run it through one of the exterior walls of a bedroom....

Goose neck it.

Forgot to ask this one earlier....what diameter of pipe do I need for this? It's a 105K boiler and a 30K water heater in an open 900 sqft basement. I'm actually puzzled by the need for the air supply, but the guy who's servicing our water heater (under warranty) won't do the work until after one is installed.

By code, 68 sq inches of cross section. 9" round. Many contactors just run a single 6".