Insulating hearth to make insert radiate more heat?

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Amin1992

Feeling the Heat
Oct 9, 2019
334
PA, USA
Hey guys. I know I've posted a lot about using a semi-flush wood stove insert without blower on here. Hope youre not annoyed with me as I've really enjoyed the discussion and appreciate all the advice.

I'm not using the insert with a blower. Anyway, I had a thought. What if I insulated the brick hearth that the insert sits inside, behind the trim piece. Would that help keep heat from escaping through the brick, and help it to radiate to the trim and into the room? Or is that just asking for overheating issues?

Just an idea and was curious what you guys thought. Thanks!
 
Is the other side of the brick inside your house or outside? If it is inside, you won't really have any gain. If it is an outside wall, it will likely help, some.
 
Is the other side of the brick inside your house or outside? If it is inside, you won't really have any gain. If it is an outside wall, it will likely help, some.

The fireplace is on an exterior wall and chimney is on exterior, so I think it could help. I was just nervous about causing a fire hazard or potentially causing the stove to overheat.

Anyone have experience with this? Think I could just use ceramic fiber / ceramic wool?
 
Insulating behind the insert would probably help more, but as the temperature of the insert goes up, so might the need for a blower to moderate the stove temperature.

Are you burning in the insert now?
 
Insulating behind the insert would probably help more, but as the temperature of the insert goes up, so might the need for a blower to moderate the stove temperature.

Are you burning in the insert now?

Hi begreen, good to hear from you again. I don't want to create an issue by insulating as the blower is currently disconnected and not sure when/if I'll repair it. Wanted to try insulating to help push radiant heat out a bit more but if it's ineffective or dangerous, definitely dont want to do that!

I am not burning right now as I need a flue installed. Previous owner did not install correctly and attached insert to the terra cotta original chimney, so we are playing it safe and waiting to use it until our scheduled flue install in August.
 
I would wait until next fall before worrying about this stuff. Run for a season with the stove and see if it meets your needs. The room is small so it's really going to be about distributing the heat out of the room. Adding more is just going to compound the issue.
 
I would wait until next fall before worrying about this stuff. Run for a season with the stove and see if it meets your needs. The room is small so it's really going to be about distributing the heat out of the room. Adding more is just going to compound the issue.

Good point, can you tell I'm excited? haha. I suppose i was just trying to plan ahead and accomplish some things before next winter but youre right, I need to just wait and see. I was checking out your stickied post on burning a fire with the various temps, and it's great to see the stove top eventually hits the 600F range! Very cool post and I'll utilize that when I eventually start my first fire.

Anyway, thanks for the advice. We'll see how she does and if need be, I'll try insulating and see if it helps. Was just curious if that was a big mistake and didnt want the stove to glow red or burn the house down because that would be my bad luck ha.

Thanks again
 
Hi begreen, good to hear from you again. I don't want to create an issue by insulating as the blower is currently disconnected and not sure when/if I'll repair it. Wanted to try insulating to help push radiant heat out a bit more but if it's ineffective or dangerous, definitely dont want to do that!

I am not burning right now as I need a flue installed. Previous owner did not install correctly and attached insert to the terra cotta original chimney, so we are playing it safe and waiting to use it until our scheduled flue install in August.
They so booked up they can't get to until August? or is that just when you want it done?
 
They so booked up they can't get to until August? or is that just when you want it done?
Unfortunately it's a hefty job at around $2.5k and I need some time to save up... so I went with August which is before fall!
 
I can answer your question although it may not matter anyway.

Just this morning I was checking temperatures around my insert with the IR gun. Top of my princess insert was 423 deg with air just cut to low getting ready for my all day burn. I looked at the brick directly above the insert shroud, and got 123 deg. Brick on the right and left side just off the shroud was around 83, house was 72. I do have a block off plate and roxul around the rear of my exterior brick fireplace. Was 23 deg outside with light winds when I took this measurement.

If you ran your unit without the shroud and insulated behind, you may get some convection and that might make a small difference. Then you would have visual issues looking at the stove carcass. Probably not enough to swing room temperatures.
 
my flush insert would be worthless without a blower. You might be wasting money(wood) by burning without a blower, more than the cost of a new one. At least break even in a year or two, who knows. I know they are expensive, i just replaced my two blowers for $400.
 
Luckily my insert is a semi flush (sticks out 6-7") and it's in a small room, can't remember what I measured but i was something between 140 and 200 sq ft. Outlet is far and hate running an extension cord and using electricity kind of takes away from the simplicity of a fire for me. Going to try out with no blower and see how it goes. Thanks for the tip.