Have another question for everyone. The more that I look at my basement install I have to make changes. I will be increasing my vent to 4" but as I am watching this blizzard cause drifts by the basement casement window I have to go vertical again after going through window. Vent would be as follows, cleanout tee at stove, 4' vert., 90, 2' horiz. to go through window, then cleanout tee again then 1-2' vert. and finally vert. cap. total evl is not bad but I am concerned with the 2-tees and the 90. I have no other choice. I can dig below window but it would probably fill up anyways. There is no other location that I can put this thing. Any advice appreciated.