Heat Shields? Single wall or Double wall?

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tiber

Feeling the Heat
Hearth Supporter
Oct 4, 2009
453
Philadelphia
The plans are in with the township, but the building inspector keeps weird hours and they said it might "take up to two weeks" for a yay or nay. The plans consisted of submitting a drawing I drew myself with measurements and materials indicated.

I was tempted to submit in crayon.

After that I have to get the actual building permit and the scratch together to make this project happen. With the wife out of work, god knows when that's going to happen. If I hit the lottery this tax season, this'll come along quicker.

When I did the drawings, I did them with a single walled stovepipe in mind figuring I would get more heat into the room. This is OK. Then someone else suggested that I would want to revise these to put heat shields on the stove. People playing along at home will remember that I'm going to buy a jotul oslo when I stop being poor. It has optional heat shields. He suggested that the stove would put out more heat with the heat shields installed. He had suggested they act like radiators. This seems wildly counterintuitive so I figured I would ask the experts...
 
A rear heat shield on the stove will act as a deflector and radiate slightly more heat into the room. How much? Who knows.. Also, instead of using double wall pipe, you could use single wall pipe with pipe heat shields. This will give you the clearance reduction while at the same time letting some more radiant heat into the room off of the pipe.
 
tiber said:
The plans are in with the township, but the building inspector keeps weird hours and they said it might "take up to two weeks" for a yay or nay. The plans consisted of submitting a drawing I drew myself with measurements and materials indicated.

I was tempted to submit in crayon.

After that I have to get the actual building permit and the scratch together to make this project happen. With the wife out of work, god knows when that's going to happen. If I hit the lottery this tax season, this'll come along quicker.

When I did the drawings, I did them with a single walled stovepipe in mind figuring I would get more heat into the room. This is OK. Then someone else suggested that I would want to revise these to put heat shields on the stove. People playing along at home will remember that I'm going to buy a jotul oslo when I stop being poor. It has optional heat shields. He suggested that the stove would put out more heat with the heat shields installed. He had suggested they act like radiators. This seems wildly counterintuitive so I figured I would ask the experts...


I'm glad I don't live in that township. Hell, I don't even need a permit. My township didn't even care that I was installing a stove. The insurance company was pretty easy also.

I disagree with the heat shield. The one I have on the Intrepid does not hold heat and does not 'act as a radiator'. In fact, even when the stove is hanging out at 650 the heat shield is barely warm to the touch.
 
a heatshield REFLECTS Heat. Not a ton, but it does. Flat metal behind a hot thing reflects heat back at the hot thing
 
I'm with BB on this one for sure. No permit, no fee, no inspection. I am friends with the county inspector, and he has seen my ongoing install, and all he said was that I was way ahead of anything he had ever seen done for a stove install.
 
The plans aren't really a requirement, they're the township playing nice with me over the inspection. It's not the "minimum official process". The official process is you buy the codes book, apply for a work permit, do the work, and then the inspector comes out and makes sure this is kosher. The building inspector here doesn't do it full time (ugh) but he seems nice if he's not telling me to simply "hire someone with a license". Gordo lives in the next municipality over and he's more run and gun than me and simply opted to get a permit and argue with the guy after the fact if it didn't pass (it did).

I'm not worried about the insurance company. My mother in law worked for State Farm for 20 years and she said they can't really argue if it passes code. I need to notify them about the install when it's done.

So when I drew these puppies up, and hopefully I'll get a call today telling me this is a go, I opted not to use the heat shields and I opted for clearances for single walled pipe. I think I did the right thing, but possibly for the wrong reasons. Why would you want to put heat back into the stove? What effect will this have on the blower?
 
Wow man...

I would have built the thing to spec, installed the stove and THEN rang the building inspector (if your insurance company wants you to) and tell him "This was all here already, we just never used it. I just want it inspected." Scew those work permits, its your house. You dont need another mans permission to work on it. Paying for permits is nothing short of extortion. Be SAFE and build it to code and see what the insurance company wants. Sorry just my rant.

Anyway, as for heat shields. They heat up and the space between them draws a convection current. Basically cold air enters the bottom and goes between the stove and sheilds gets real warm then circulates around the room. It does have some real value. Thats why they dont get supper hot on the outside. Because they are being cooled through convection current. The shields do a good job of converting radiant heat (which heats objects in line of sight, but not much airspace) to convention heat (which heats the air essentially).
 
nojo said:
I would have built the thing to spec, installed the stove and THEN rang the building inspector (if your insurance company wants you to) and tell him "This was all here already, we just never used it. I just want it inspected." Scew those work permits, its your house. You dont need another mans permission to work on it. Paying for permits is nothing short of extortion. Be SAFE and build it to code and see what the insurance company wants. Sorry just my rant.

I would have, but the home was inspected at sale per PA law. Since the township is small and the inspector only works once or twice a week, you can be sure there's only one of them and I'm sure he's got a good memory. Just to argue the townships side of this - it's Valley Forge. There are buildings here from literally before we were a nation. The house up the road is this beautiful converted barn which I almost bought until I figured out I'd have no place to put the kids. Just in the townships defence, there's a lot of historical stuff around here which simply doesn't meet code. It's cool stuff, but we've got chimneys here with 200+ years of creosote and wiring done really badly. My house happened to be build in 1966, so I roll my eyes at some of the checks, but I understand the reasoning.

Anyway, as for heat shields. They heat up and the space between them draws a convection current. Basically cold air enters the bottom and goes between the stove and sheilds gets real warm then circulates around the room. It does have some real value. Thats why they dont get supper hot on the outside. Because they are being cooled through convection current. The shields do a good job of converting radiant heat (which heats objects in line of sight, but not much airspace) to convention heat (which heats the air essentially).

So two votes for yes shields and one vote for "they don't do much"? I still would like to know if the shields are a requirement for the blower.
 
On OUR stove, the heat shield is required for the blower. I didn't see where you said what stove you are installing, but in our owners manual it gave us the requirement, and once we recieved the blower and heat shield, I see why you have to use the heat shield with the blower.

edit: also, I doubt a heat shield does much to put more heat into the room by itself, but it for sure does "something", it reduces clearances. I believe that to be it's main function. In our case that was also good, but we wanted the blower too.

another edit: ok, after rereading your 1st post.. an Oslo.. here is quick link to the manual..

(broken link removed to http://tinyurl.com/oslomanual)

look in there and see what they say..
 
tiber said:
I would have, but the home was inspected at sale per PA law. Since the township is small and the inspector only works once or twice a week, you can be sure there's only one of them and I'm sure he's got a good memory. Just to argue the townships side of this - it's Valley Forge. There are buildings here from literally before we were a nation. The house up the road is this beautiful converted barn which I almost bought until I figured out I'd have no place to put the kids. Just in the townships defence, there's a lot of historical stuff around here which simply doesn't meet code. It's cool stuff, but we've got chimneys here with 200+ years of creosote and wiring done really badly. My house happened to be build in 1966, so I roll my eyes at some of the checks, but I understand the reasoning.


Safety is a good reason to have inspections and pay a reasonable price for them. Permits imply that you have no right to modify your home or property. Im completely against permits but think inspections are a good idea.

Plus why should the town be involved? It should be insurance companies that do the inspections. After all they are ones with the most to risk?

My insurance company told me to have the town inspect the stove, the town guy wont return ANY of my calls. So I'm going to call the insurance company and see if they will come in and check it out. The town guy has zero incentive, if he never shows up I can't fire him as my building inspector and higher another one. If my insurance company however fails to provide customer service I can drop them. Town inspectors are a joke.
 
Dakotas Dad said:
On OUR stove, the heat shield is required for the blower. I didn't see where you said what stove you are installing, but in our owners manual it gave us the requirement, and once we recieved the blower and heat shield, I see why you have to use the heat shield with the blower.

edit: also, I doubt a heat shield does much to put more heat into the room by itself, but it for sure does "something", it reduces clearances. I believe that to be it's main function. In our case that was also good, but we wanted the blower too.

Jotul Oslo. That basically settles it - if I can't use the blower sans shields, then I need to get the shields. I'm pretty firmly convinced the blower is a required part of the stove.
 
tiber said:
nojo said:
I would have built the thing to spec, installed the stove and THEN rang the building inspector (if your insurance company wants you to) and tell him "This was all here already, we just never used it. I just want it inspected." Scew those work permits, its your house. You dont need another mans permission to work on it. Paying for permits is nothing short of extortion. Be SAFE and build it to code and see what the insurance company wants. Sorry just my rant.

I would have, but the home was inspected at sale per PA law. Since the township is small and the inspector only works once or twice a week, you can be sure there's only one of them and I'm sure he's got a good memory. Just to argue the townships side of this - it's Valley Forge. There are buildings here from literally before we were a nation. The house up the road is this beautiful converted barn which I almost bought until I figured out I'd have no place to put the kids. Just in the townships defence, there's a lot of historical stuff around here which simply doesn't meet code. It's cool stuff, but we've got chimneys here with 200+ years of creosote and wiring done really badly. My house happened to be build in 1966, so I roll my eyes at some of the checks, but I understand the reasoning.

Anyway, as for heat shields. They heat up and the space between them draws a convection current. Basically cold air enters the bottom and goes between the stove and sheilds gets real warm then circulates around the room. It does have some real value. Thats why they dont get supper hot on the outside. Because they are being cooled through convection current. The shields do a good job of converting radiant heat (which heats objects in line of sight, but not much airspace) to convention heat (which heats the air essentially).

So two votes for yes shields and one vote for "they don't do much"? I still would like to know if the shields are a requirement for the blower.


You miss-understood my comment. The heat shield does a fine job of blocking heat in a certain direction and I was amazed as to how cool the heat shield was to the touch.
 
nojo said:
Safety is a good reason to have inspections and pay a reasonable price for them. Permits imply that you have no right to modify your home or property. Im completely against permits but think inspections are a good idea.

Because without a permit, there's no incentive to follow through and get the inspection. More on the point a permit gives you a chance to do what I did and touch base with the person who would be doing the inspection and find out what his opinion is of the work before you spend any money and rip up your house. Without a permit, inspections would be optional and When It Goes Bad would be reduced to fire code in the books. The books are $120/per ($99 when they go on sale), I happen to have access to them through the company I work for but the permit + inspection is cheaper, and BSing with the guy is currently free.

Permits work both ways also - the permit lets you contest your tax assessment where I live.

Plus why should the town be involved? It should be insurance companies that do the inspections. After all they are ones with the most to risk?

I'm sure there's people involved in the california wildfires who have a strong argument against your neighbor simply rigging up any old fire device.

I take that back, you're problably not allowed to burn wood in california but you get the point. There's significant risk to infrastructure and utilities. Plus we're on well water for the township, they're extremely anal about how you do things because poisoning the well is a significant problem. I agree that a mans home is his castle, but unless you're totally off the grid you have to accept the fact that there's assumed risk from who you live next to also.

My insurance company told me to have the town inspect the stove, the town guy wont return ANY of my calls. So I'm going to call the insurance company and see if they will come in and check it out. The town guy has zero incentive, if he never shows up I can't fire him as my building inspector and higher another one. If my insurance company however fails to provide customer service I can drop them. Town inspectors are a joke.

That's a process versus implimentation argument. Just because it's done badly doesn't mean it shouldn't be done. If everything ran like a Ford, it doesn't mean you shouldn't buy Chevies. ;)

For the record, I'm going through the same thing you are. I left the guy the drawings with my contact information and a note about what I'm doing because I couldn't get ahold of him. I'm doing this well before I have the capitol for this project because I expect the government foot dragging to get in the way. Hopefully I get my stuff done before it's go time.
 
Wow, a fellow Audubon resident. Nice to see you here!

btw, our township can be finicky at times, but they mean well. At least they haven't let the commercial developments in like Upper Providence.
 
LEAVE MY TOWNSHIP. THERE CAN BE ONLY ONE.

UHM ON YOUR WAY OUT PLEASE REMEMBER TO COVER YOUR WOOD, THANK YOU.

Yeah I'm still waiting for the building inspector to call me back. I realize with access to the codes books I could probably pull it off on my own but I want his blessing before commencing so I can request him when the project is done.
 
tiber said:
UHM ON YOUR WAY OUT PLEASE REMEMBER TO COVER YOUR WOOD, THANK YOU.

Well, if I had any wood to cover up, that'd be nice for a chance. I am still searching for a decent firewood dealer to sell me some. Burning through envi-blocks at the moment.
 
Oh and I got all flustered when I saw Audubon and forgot to answer your original question. We have an old VC Defiant from 1979 with single wall pipe and rear heat shield. The heat shield really makes a difference, in that one can be absolutely roasting in front (the Defiant has a giant firebox and can seriously crank), but the heat is barely noticable at the back.
 
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