We picked up a small Napoleon gas stove (fireplace). It apparently requires an axial vent which is 4 and then 6 7/8". The unit is probably 30" high and the ceiling that it is going through is 7' off the floor. The ceiling I am going through it just a 2x6 roof, no attic. What parts do I need to install for the vent to pass through to the outside? I've seen tons of articles about vents passing through the ceiling, passing through an attic and then outside but, that's not my situation where there is no attic. Thoughts?
Venting through roof question
- Thread starter GregSp
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What you need is CO-AXIAL 4”x 6-5/8,” not axial 4x 6-7/8… That being said, parts for passing thru an attic are similar for your installation. The ceiling support box will be in contact with the underside of your roof sheathing.
Very helpful Bob. Thank you. I know the Co-Axial has a vent inside a vent but, what do they do? I would assume the smaller 4" vent actually vents out the carbon monoxide. What does the larger vent do? Is it just insulation or does it also allow air to enter to displace the hot air that is escaping? Next question. I can pull down enough ceiling around where there vent is going to go through the roof. Looks like I need 2" of space between the vent and any kind of insulation? Next question, (sorry, just need info so either I or a contractor can hook up the stove and not burn the house down or cause us to die from carbon monoxide poisoning. Hate that when that happens!). I will need about a 4 1/2 foot run to get into the ceiling and then another 5 foot run to get it up to the proper height above the roof. Is this just on continuous run where I can use 2, 5 foot lengths and lock them together? Does anything special happen to the actual vent itself when it passes through the roof?
The inner 4" is the exhaust. The outer 6-5/8" is the intake for combustion air. All sections of Direct Vent (DV) interlock. It does not matter what lengths you use, so the run is continuous from the flue collar on the stove to the vent cap. The DV pipe will pass thru the ceiling box, which will have the required clearance to combustibles built in, thru the flashing & storm collar to the cap. If you buy your vent system new, you will receive installation instructions. If you have any issues when you start the install, come back here & we can point you in the right direction.
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