the vents one on the out side of the house where the plumbing exits, about 7 feet from the toilet, and one on the upstairs 1/2 bath, (now the drains Wye together below the toilet or on the opposite side of the shower, and there is a vent on the kitchen sink, the water does not freeze, when the drain freezes up, and the water lines are closer to the out side walls, (this is on the down wind side of