Transition from capped masonry chimney to class A

[Hogwildz]

I would much rather have stainless rivets than regular steel in this application. Maybe contact DuraVent if concerned?

"...when using a bare steel plate with a zinc rivet, the ratio of the cathode surface area to the anode surface area is large, and the rivet will fail rapidly because of accelerated corrosion. When combining a zinc plate with a stainless steel rivet, the area ratio between the cathode and anode is reversed, and although more surface area is affected, the depth of penetration is small; the fastener should not fail because of corrosion."
http://www.galvanizeit.org/hot-dip-galvanizing/how-long-does-hdg-last/in-contact-with-other-metals

I read the same page, and was going to post it, but nah....

 

[bkoltai9]

Thanks everyone for your input.

I like the idea of using angle iron or an independent steel plate to support the transition anchor plate although I was wondering if raising it off the masonry stack, even by a little, changes the seal and the way the flue operates.

I thought I read in a thread somewhere that someone specifically chose Selkirk because their transition anchor plates are 25x25. I couldn't find such an item and I had trouble figuring out what is what amongst their product lines. I've read people saying great stuff about metalbestos, but I found a whole array of sure temp, ultra temp, super vent, etc. Which of these product lines is the one I'd actually want?

Are there other options I should consider besides Selkirk, duravent, and Olympia?

 

[begreen]

The steel plate should be siliconed to the chimney, then the class A anchor plate siliconed to the steel plate. Use a good quality silicone like GE Silicone II and no water is getting through there. It will be a sealed unit. Even it it wasn't it wouldn't effect draft which is dependent on the seal of the liner to the class A. FWIW I didn't find an equivalent transition plate in the Selkirk catalog. Did you get a part number?