I installed my block-off plate for my quadrafire 3000I even with the lintel (6" above insert top) and used copper plate left from roofing job. Is there any problems going below the connection at my 22.5 deg ss elbow? Is copper plate(22 ga.?) acceptable code material? Is the flashing of the rain cap on top of the old ceramic liner considered a top block-off plate when caulked? Lastly, is the city of Livonia inspector (just west of Detroit) going to know these codes? I want this thing done right!! Thanks for any input, Choco. p.s. pics and more details of my new install coming shortly.
block-off plate(s) positioning
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I would have no problem using 22 gage copper. As for your inspector I can't say what his code knowledge is. The best way is to form two seals the damper and top plates
Requiring them both has been a heated discussion here and some what vague in code. There is enough language there, for me to require the damper block off plate
Requiring them both has been a heated discussion here and some what vague in code. There is enough language there, for me to require the damper block off plate
webbie
Seasoned Moderator
Yes, I think copper is fine and also the best place (in general) is so it contacts the read of the lintel.
We have discussed at length the advantages of a bottom plate, even though a top one will often pass code and meet the manufacturers specs. The bottom one will give you more heat, better draft and other advantages.
In my experience, most inspectors do not know all this stuff. Elk is a true-blue woodburner who goes out of his way to learn all that he can. This is not to critique inspectors, but if you saw the code books (thicker than telephone books), you would see why it is impossible for one person to ever know everything.
You may get lucky, you may not - but it sounds like you are making certain yourself to do a quality job, and that goes a long way.
We have discussed at length the advantages of a bottom plate, even though a top one will often pass code and meet the manufacturers specs. The bottom one will give you more heat, better draft and other advantages.
In my experience, most inspectors do not know all this stuff. Elk is a true-blue woodburner who goes out of his way to learn all that he can. This is not to critique inspectors, but if you saw the code books (thicker than telephone books), you would see why it is impossible for one person to ever know everything.
You may get lucky, you may not - but it sounds like you are making certain yourself to do a quality job, and that goes a long way.
ozarkjeep
New Member
- Nov 6, 2006
- 407
along the same lines here.
I did NOT install a blockoff plate back in November when I put in my insert, I do plan to put one in this spring though, mainly for the idea of more heat output of the stove.
without any need for argument, is my logic correct?
If there is an insulated plate above the insert, basically more heat will come out of the front of the insert?
it works fine as is, drafts well, and makes good heat, just looking for an improvement that can be had simply, and if it makes it even safer, then bonus!
I did NOT install a blockoff plate back in November when I put in my insert, I do plan to put one in this spring though, mainly for the idea of more heat output of the stove.
without any need for argument, is my logic correct?
If there is an insulated plate above the insert, basically more heat will come out of the front of the insert?
it works fine as is, drafts well, and makes good heat, just looking for an improvement that can be had simply, and if it makes it even safer, then bonus!
MrGriz
New Member
You are correct. One of the benefits to the block off plate is to keep heat from 'escaping' up into the chimney. I guess the safety factor is a bonus. ;-)
DriftWood
Minister of Fire
Yup, you are stopping the heat from going to the cold in the chimney. It will go some where, out the front would be best!
ozarkjeep said:
I'm in a similar position. In my case the vertical pieces of the surround (left and right of the stove) sometimes get warm, never HOT, and often cold, due to (I'm assuming) the air rushing between them and the brick wall that they're about 1/2" away from.
I figure that if heat from the surround is being lost due to the airflow, heat is being lost from the sleeve that the insert sits in (and that creates the air channel that the fan blows through) as well. Additionally, all this air flow is really air I've already warmed rushing out of the house.
To enforce what you've said, to be entirely effective, the blockoff plate should be insulated (with something that is rated to withstand the heat!) as well. Stopping the airflow is only part of the equation, reducing heat transfer is the other.
-Hal
Highbeam
Minister of Fire
All of this air"rushing" out of the house... just where do you think it's going? You do have a top seal at the chimney top don't you? I could understant rushing air if the top of the chimney wasn't sealed but it is. I expect the air temp between the SS liner and the clay chimney liner to be quite warm and certainly not rushing anywhere whether you have a bottom plate or not. I seem to be confused.
Highbeam said:
If your chimney were an interior situation what your thinking would be closer to that way But an exterior chimney totally outside the insulation envelope sucks the heat out readilly a the bricks never get warm enough exposed to cold warm air will rise also threw cold air ant that thin piece of metal top may stop most draft but it offers litt resistance to cold entering any warmth has long gone, before it gets near the top
Hogwildz
Minister of Fire
Highbeam said:
If the chimney is masonry, yes a top cap keeps the warm air in, but a block off plate wqouls stop much more warm air from filling that cavity, and the masonry conducting it to the outside. With a top plate & damper block off plate, the air is now dead air and acts as an insulator. Not to mention less heat going up, more going out into room. And Also less heat for the old chimney to conduct. The whole point in bottom plate is A. Safety, then B. keeping heat going forward & not up to be conducted out.
MrGriz
New Member
Elk and Hog did a much better job of explaining than I did.
Without a block off, it's not as if the heat is running out the door like a teenager with the keys to the car. The heat is still stopped by the top plate and is kept in the chimney. Unfortunately, unless you have an exposed interior chimney, this is of little use. With an exterior chimney, the heat is just transferred through the masonry to the elements. The block off plate helps to trap and radiate more heat back into the room, which is the ultimate goal.
I think Elk and Hog still did a better job, but at least I was able to throw my .02 in. ;-)
Without a block off, it's not as if the heat is running out the door like a teenager with the keys to the car. The heat is still stopped by the top plate and is kept in the chimney. Unfortunately, unless you have an exposed interior chimney, this is of little use. With an exterior chimney, the heat is just transferred through the masonry to the elements. The block off plate helps to trap and radiate more heat back into the room, which is the ultimate goal.
I think Elk and Hog still did a better job, but at least I was able to throw my .02 in. ;-)
Highbeam
Minister of Fire
Oh OK let me try collect and regurgitate. It is not a fan blowing type of heat loss, no actual flow of hot air but rather a conductive loss like holding an ice pack against your forehead. That air cavity in the chimney stays cold and since it is exposed to the room at the bottom it sucks heat out of the room. The heat rushing out is what confused me since I was imagining an actual air movement. It would appear that insulating the block off plate is just as important as sealing it since the ice pack will still steal heat through a metal block off plate alone perhaps just as fast as it would if the block off plate were missing.
Thank you guys for helping me with this. My LOPI is installed per the current stove manual with no lower block off plate, the installers thought I was nuts to suggest one. I might be nuts but I think they were just lazy.
Thank you guys for helping me with this. My LOPI is installed per the current stove manual with no lower block off plate, the installers thought I was nuts to suggest one. I might be nuts but I think they were just lazy.
GVA
Minister of Fire
It's Thermodynamics-------- Energy is transfered from a warm to a cold body....... and unfortunatly since heat want's to rise it's more apt to head up an open cold chimney than a room with a cold floor ;-P
Hogwildz
Minister of Fire
ozarkjeep said:
When making the block off plate. I recommend considering making it out of 2 or 3 pcs. I installed mine after liner & insert were in place and connected. I did 3 pieces.
one on each side overlapping where they were cut around the liner, then one piece in the rear of liner again overlapping the other 2 pcs. Sealed along the edges at the steel fireplace with 600° silicone. The plate overlaps & around the liner with furnace cement. Try and get as tight a cut around the liner as you can. A good suggestion for packing around the liner is rope gasket like around stove doors. B.B. gave that good advice, I had mine done prior to that though. I have a ton of furnace cement around mine. Hoping it won't crack and fall down LOL. I used self tapping sheet metal screws to attache the perimeter of my block off plate to the steel fireplace around the egdes.
If yours is masonry, you can use small tapcons. You could try masonry nails, but I think they would be more trouble & hassle.
Not to get into my usual tug of war over insert block-off plates but, safety aside, your insert already has a top heat retaining shield if the convection shroud surrounds not only the sides but the top of the firebox.
Insulation on top of it would help retain heat, but it is questionable just how much more heat another piece of tin six inches above it would retain.
Insulation on top of it would help retain heat, but it is questionable just how much more heat another piece of tin six inches above it would retain.
Hogwildz
Minister of Fire
Highbeam said:
I haven't examined the top seal that the installer put in, but based on the dust that collects in horizontal mortar joints that go behind the surround, I'm pretty sure there's quite a bit of air movement through there. I'll check the top seal when I clean my chimney in the spring, I suspect that will need some help as well
-Hal
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