blocker plate question.

[mainstation]

I have an Regency Insert and this season am considering "fabbing" and installing a Blocker plate. Have burned for years with inserts and have never had a Blocker plate. Couple of questions: Does it help with heat and stove efficiency ? And, Can I use regular roofing steel or is there specific steel, painted/nonpainted required. ?
Thanks

 

[begreen]

A block-off plate can make a nice difference, especially with an exterior chimney fireplace. Regular sheet steel is fine.

https://www.hearth.com/econtent/index.php/wiki/Why_damper_seal_is_needed/

 

[sandie]

My chimney sweep did it with a few pieces of metal, then screwed them together to form the blocking plate. took about an hour and half to get it all together but a good job. No silicone of furnace paste. Held in place with screws and strips of same metal sort of like L to hold to back wall of chimney. WORKS

 

[burleymike]

While I cannot tell you how well it works since I am still waiting to get my insert. I got some work done on my block off plate today. I just went to the local HVAC shop and asked for a 2x3 piece of 26ga sheet metal, 10 minuets and $3 later I had my block off plate. Today I made a cardboard template and will cut it out tomorrow. I will post some pictures when I get it done. I might just mount it and cut a 10" square hole in it and then put a 16" square plate with a hole in the center for the liner over the 10" hole. That way I don't have to have the insert here to take exact measurements.

I do believe the block off plate will keep a lot of heat from going into the masonry. Even on the coldest days we never had any snow stick to the top half of the chimney.