To install a block-off plate , or not?

[wood-fan-atic]

Hey all! I was thinking about installing a block-off plate this year. I'm not really sure it would have much effect, though. It is an interior chimney, right in the center of my house, between my kitchen and living room. It is open on both sides, so access is super easy. I'm just not sure it will have much positive effect,though. I have a 6" double-lined , stainless liner, and no creosote problems to speak of. Does anyone have any 'before and after' performance experience when installing a block-off plate in an interior chimney?

 

[pen]

To me, it doesn't hurt. Even though w/ an interior chimney it's not as big a deal, you are still sending heat up the chimney that will warm the portion that is sticking above your roof line. A block off plate is really nothing special, KOA wool stuffed around that liner would do just fine. It's not like it's a freestanding stove in there where you'd be able to peek around it and see what is blocking this area.

Some say straight fiberglass (w/ the kraft back removed of course) works fine also. Other's don't recommend it because of a possibility of out gassing at high temps.

For me, it would depend on how hard it would be to do it. If it were a real pain I'd leave it as is.

pen

 

[mhrischuk]

Personally I think if you stuff the cavity around the flex pipe well, including up inside the smoke chamber and then a couple of horizontal layers precisely cut for a good seal is all you need. If you ask me, the metal plate itself will suck heat from the stove and help radiate it up. I think all the metal plate does is stop any air movement. If you think about it, with the top blocked off and the bottom stuffed, there isn't going to be any convection possible inside that chimney's dead air space. I think after I stuff the smoke chamber with Roxul, I'll put a flat piece of it up there to act as a blockoff plate and secure it with stainless wire and masonry nails. Just wind the wire around the nail heads.

A better solid blockoff plate should be made out of a high heat insulation board not a conducting metal.

BTW, my Equinox has a damaged baffle. The baffle is made of a super high heat ceramic material. I think I'll use it for the blockoff plate!

Thanks! You all got me thinking!