Question on connecting stove pipe sections

Generaly - use 3 screws at each connection (ss self tapping). Pre-drill a pilot hole first. Then use either a high temp caulk or gasket cement around the seam and you should be all set.

Is this pipe being used to vent a wood stove or coal stove? If so, please don't use silicone of any type. If you must use a sealant use furnace cement. Typically, sealing the joints is not needed. Use a drill to pre-drill three holes in a triangular position from one another and install sheet-metal screws with a screw driver. Or, as we do every day, use a power drill with a 1/4" driver and some self-drilling 1/2" screws, in either black or stainless steel.

Double or single wall? Usually double wall doesn't need to be sealed. Often single wall does because the seams create un-even spots and gaps. Use furnace cement to seal it.

Never had to seal the joints of the single wall. If theres smoke coming out there you have other draft issues.

Sorry to revive an old post.

Can someone give me a specific example of a brand for stove pipe joint compound / sealant? I just want to be sure I have the right stuff. I bought some stuff from Lowe's made by Imperial that came in a small plastic jar (like a wood putty type jar) that is heat resistant to 2000 degrees. I have seen some caulking tubes that are suppose to be high heat as well. I think they were made by DAP.

For those who don't seal their joints and only use sheet metal screws, how do you get a good seal? I have to use the snap lock type of stove pipe because that is the only thing available in my area. Personally, I don't like it. It tends to leave a pretty good gap near that snap lock seam. I am considering using a joint sealant just because I don't want to introduce outside air into the chimney. Is everyone in agreement that will be the best route?

Rutland furnace cement.

I've never sealed a stove pipe and never had a problem. I use self tapping screws on the stove downstairs cuz the pipe makes two turns, but upstairs it's straight up so I don't use any.
I agree, if there's a problem with the seams leaking, then you have a draft issue.

On single wall pipe, code REQUIRES three screws per joint, preferably spaced evenly around the pipe. It does NOT require sealing, but it is not a bad idea to do so. The other important point is that the ridge above the crimps on the male end should be inserted far enough to be touching the edge of the female socket If these two things are done, you should get a pretty tight seal, even without the sealant. Also remember that the male end should always point down / towards the stove, and the female point up. This seems counter intuitive in terms of smoke flow, but the idea is to funnel any liquid creosote that forms back down and into the stove.

Most joints this should not be a problem, except possibly on the stove connector - many manufacturers make the connector collar shorter than the length of the ribs on the pipe, so if you put it in to the stops the ribs are still showing - this is NOT acceptable, you should either use a special "starter section" of pipe with shorter ribs, or trim a standard peice so the ribs are about 1/16" shorter than the depth of the collar so that the rib touches the collar when you put the pipe into the stove.

If you do use sealant, look for refractory furnace cement, such as Rutland, or the various stove maker "private label" versions of the same stuff. Do NOT use high-temp silicone, it does not have a high enough temp rating, and will melt out of the joints, often with accompanying smoke, possible flame, and much stink...

The sealant isn't really required, because a properly fitted joint (even with snap locks - which I put together with the locks next to each other) will have minimal leakage, and that leakage will be letting air into the stack, not letting smoke out.

Gooserider