I am having a house built that will have two ‘stacked’ gas fireplaces, one in the lower level (basement) and one in the main level. By stacked I mean one right abve the other. The installer wants to vent the lower thru the foundation. I’d like to vent them both thru the side wall. That would mean bringing the lower unit’s venting up thru the floor (behind the upper unit) and out the wall. The upper unit would be vented higher up the wall. I’m told that the exterior separation only needs to be 1 foot.

Does sound right?

Thanks,

Richard