Do I NEED a block-off plate for my insert?

[wood-fan-atic]

I have been seeing alot of you talking about installing block-off plates above your inserts and hearth-mount stoves. My insert (Flame 1.9-I made by SBI,similar to Osburn and Drolet models) is NOT on an outside wall. It is directly in the middle of the house. I have a Levit Ranch (in Levittown, duh), and every house in this town was built between 1947-50 on a concrete slab with a chimney smack-damn in the center. The house is two stories, with the stove on the ground floor. I have no problems with draft either in the stove, or cold air seeping down around the SS liner. I do have access to the back of my insert which most people do not (the original fireplace was open on both sides - kitchen and living room), so it would not be that difficult to install if I had to. If I did, could I just insulate a few feet above the plate with mineral wool or something similar( and affordable)? What would be the benefits of installing one, since I'm not experiencing any problems right now? I defer to you - my trusted gurus.

 

[btuser]

Because yours is an interior chinmey I doubt if it would help, but I don't have one on mine and have been fuddling with the idea of one. I'm on an exterior wall however.

 

[vvvv]

warm air migrates up & condenses when it hits cold brix unless it is blocked

 

[ROBM1093]

Hi, I also have a Levitt ranch Long Island, just wondering what insert do you have and does the heat get to the two back rooms? My fire place is 35 x 21 high is yours the same or did you make the opining higher to fit the insert?

 

[weatherguy]

I have a center chimney too and the first three years I didnt have a block off plate. I finally got around to doing one this year, I stuffed roxul around the liner and cut out a piece of sheet metal I got from Home Depot. It makes a pretty big difference, I immediately raised the temp 3 degrees in the house with the BO plate. A lot of the heat was rising up the flue and getting absorbed by the masonry, now most of it stays in the living area. For the cost (about $50) its worth it in my opinion, wish I would have done it the first year.

 

[dafattkidd]

Hi, I also have a Levitt ranch Long Island, just wondering what insert do you have and does the heat get to the two back rooms? My fire place is 35 x 21 high is yours the same or did you make the opining higher to fit the insert?

Rob, woodfanatic hasn't been around much as of late. That being said, i hope he replies it would be good to hear from him.

 

[Hogwildz]

Yes, heat kept in the room/house, is heat that is not going up the flue cavity.

 

[CheaperthanYou]

How do you like that insert in the ranch? i have a ranch and am looking for something to put in the brick

 

[AnalogKid]

An old thread that got bumped.....

So is a block-off plate all that much better than just filling the openings between the liner and chimney opening with insulation?

 

[dafattkidd]

How do you like that insert in the ranch? i have a ranch and am looking for something to put in the brick

You might have more success starting your own thread addressing the specifics of your situation. Generally you find the best gauge for heat output is firebox size. Once you determine a desired firebox size you can start looking at specific units that fit in your fireplace and fit the aesthetic you're looking for. Whatever insert you put in there will put out a lot more heat than an open fireplace. Good luck!

 

[Hogwildz]

An old thread that got bumped.....

So is a block-off plate all that much better than just filling the openings between the liner and chimney opening with insulation?

Insulation does not stop airflow.

 

[AnalogKid]

Insulation does not stop airflow.

Fair enough, but if the top plate is sealing off the top of the chimney, how much air flow is there really going to be?

 

[Hogwildz]

Fair enough, but if the top plate is sealing off the top of the chimney, how much air flow is there really going to be?

Not a ton of air, but what will happen, is heat will migrate up the old chimney cavity and be transferred to the great outdoors through the masonry.
A sealed lower block off plate will force a majority of that said heat back out into the room and home instead.
Just stuffing PROPER insulation into the cavity around the liner is done by some, and may work ok. Other use fiberglass insulation, which as far as I am concerned is not the right material for that job. Myself, I decided not to cut corners, and am happy with the results.
The other reason I installed the plate, is for an additional level of safety.

Stuffing insulation may work ok, but when it comes to burning and heating with fire in the home, I won't cut corners. That is just me in my home. Do as you feel fit for your home.