Wall protectant heigth?

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Erich

Member
Hearth Supporter
Nov 8, 2008
28
Pennsylvania
New member, so far seems like great information here. Anyway, I am putting in a woodstove, and for space, I am building a heat resistant penel behind the stove so I can move the stove closer to the wall. I am using Durock with ceramic tile over it. My question is how high should the ceramic wall be? I know I need to space it away from the wall one inch, and also have a space under it, but I haven't found anywhere that says how high the wall needs to be. I would guess 4 feet high would be about right, and just because I tend to overbuild things, I was going to go 5 feet high. What do you guys think?
 
I'll assume you have single wall pipe coming up out of your stove.
The clearance, at 28" above the flue collar, from the single wall pipe to an unprotected surface is 14".
This is from my stove's manual. Your code may vary.
 
Erich said:
... Anyway, I am putting in a woodstove, and for space, I am building a heat resistant penel behind the stove so I can move the stove closer to the wall. I am using Durock with ceramic tile over it. My question is how high should the ceramic wall be? I know I need to space it away from the wall one inch, and also have a space under it, but I haven't found anywhere that says how high the wall needs to be. I would guess 4 feet high would be about right, and just because I tend to overbuild things, I was going to go 5 feet high. What do you guys think?

Depends, your stove pipe wall protection panel needs to extend to the top of the wall if the stove pipe goes out the ceiling.

If your extension of 5' takes the stove pipe protection panel to the ceiling then you have fulfilled the requirement for protection.

Look at figure #1 at

(broken link removed to http://www.cdc.gov/nasd/docs/d001001-d001100/d001052/d001052.html)

then figure #2 at

(broken link removed)

Good luck with it.
 
Thanks for the replies. I am using single layer stovepipe inside the house. The top of the stove is probably 4 feet tall. The stovepipe comes off the top of the stove, and I am going to go 45 degrees from that to the wall behind the stove about 6 feet high I would guess is where it would penatrate through the wall.
 
What kind of stove is this? Do you have manufacturer's documentation showing required clearances to combustibles for the stove? Do you know whether or not it's permissible to reduce those clearances by installing a heat shield? If it's an old stove and you don't have any information on it, then you need to default to the standards set forth in NFPA 211. We can help you with all this. Above all, you want to make sure from the outset that what you're doing will be safe, from the stove to the connector pipe, to the transition to Class A chimney pipe. Rick
 
Erich, welcome. We need to know the stove make and model first.

Single wall pipe requires 18" clearance from combustibles. Depending on the design, it may be helpful, safer and aesthetically nice to extend the wall shield above the exit thimble where you transition to class A pipe or the chimney thimble. As an alternative, double wall connector pipe often makes for a safer, better functioning stove with lower clearance issues. Something to consider.

If you can post a picture of the current location, it would help a lot.
 
It is an old Morso stove, and I have no documentation on it, and I have looked! The way I understood it, if you didn't have the manufacturers specs, that there were "default" specs to use. And I read that the default clearances for unknown stoves were 36" from the wall, or if a wall protectant was used you could reduce that to 12". I planned on keeping around 15" just to have some wiggle room.
Also, I have no problem going much higher on the wall protectant, I just don't know how I would penatrate through that, AND the combustable wall.
 
You've done your homework...good for you! (Lots of folks don't, then get all frustrated when they learn the truth). The numbers you're working with are correct. Don't forget about the fact that the stovepipe has clearance requirements too. The basic rule is that vertical single-wall pipe needs at least 18" from an unprotected combustible surface. You'll also have to provide hearth protection beneath the stove. How are you planning the transition from stovepipe to chimney pipe? Rick
 
Erich said:
Thanks for the replies. I am using single layer stovepipe inside the house. The top of the stove is probably 4 feet tall. The stovepipe comes off the top of the stove, and I am going to go 45 degrees from that to the wall behind the stove about 6 feet high I would guess is where it would penatrate through the wall.

Ok, that being the case then look at this stove set up at

http://204.84.39.7/Images/wdstove2003.pdf

Installation 3 - Through The Wall

(broken link removed to http://www.woodstove.com/pages/prefab_chimney.html)

The Clearance Table

(stove pipe can be within 12" of a protected wall)

(broken link removed to http://www.woodstove.com/pages/hearthplan.html)
 
Thanks for the links Dave, some great stuff there. The trouble I am seeing is pretty much ALL of the stovepipe info I have found, shows the pipe going pretty much straight up through the ceiling. I was hoping to go out the wall, then go 90 degrees up through the eves. (My eves stick out 48") Without getting into too much detail, it would be very difficult for me to go through the ceiling, but if I have to, I have to. I'm not very good with the makin' of the words, so I drew up a quick sketch of what I hoping to do. You can see the wall protectant, and why I am questioning how to set it up. I want to use a T outside, so I can pull the plug out of the bottom and clean it out without getting out a ladder.

Looking at that picture, I am now wondering if I would be better off just using one 90 degree bend instead of the 45, there would be less surface area near the combustable part of the wall.
 

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If you are using single wall pipe on the interior, the way you have shown it is better than a 90 into the tee (another 90), especially if the exterior class A pipe is short. Just be sure that the top of the single wall pipe at the elbow going through the wall thimble is at least 18" from the ceiling. Also, the diagonal surface of the single wall pipe has to be at least 18" from the wall, unless there are pipe shields on it or wall shielding.

All of this gets easier if you use double-wall connector pipe on the interior. The added benefit will be warmer flue gases and potentially less creosote condensation.

PS: Is that a Morso 1125? If so, contact Wrigley for some more info:
https://www.hearth.com/talk/threads/24987/
 
Yes it is a Morso 1125!! Thanks for that, I will get in touch with him. It's weird to actually see a picture of it, I have searched and not found anything. Now, 18" from the wall, measured from where? Close to the wall it is impossible to be that far away, because it is heading for the wall!
 
Not impossible if the class A branch coming from the exterior tee, through the thimble, projects deeper into the room. With double-wall, you only need 6" of class A projecting into the room.

I think you are the 3d 1125 we've seen this season. Search the forums for more posts. We've seen a couple beauties.
 
Erich said:
Yes it is a Morso 1125!! ...

Hi Erich,

We just got back from trying to keep the U.S. economy afloat.

Is this your stove? https://www.hearth.com/gallery/pics/woodcoal/source/1125.html

(That flue looks like it is 8" to me. Did Morso make two different models?)

For the best flue draw, & less creosote, it is best to go straight up thru your ceiling if that is possible.

(If your sketch is anywhere near scale then you are going to climb a ladder or else you are one long drink of water (7'-0" at least) & or be good at "flat footing it". :lol: Need to keep in mind that one day you might need to sell your house. What do you think the R.E.A. is going to say about your clean out needing an N.B.A. star?)

If not, then your next best choice is go out the wall somewhat lower (2'-0" or more) in order to be able to get a grip on the clean out, that is unless you "leap tall buildings at a single bound". :lol:

For reasons known only to the lizards of ID a "T" does not act like a 90* elbow. So if you punched into the wall at a lower elevation, that most normal people do not get a nose bleed at, you should be good to go. ;-)

Good luck with it.
 
Nice, it looks to be in great shape. They did have a lot of 70's colors like avocado green and mandarin orange back then.
 
Ok, assuming that Erich's Morso is out of the `70's,

1.) did Morso make internal cat back then?

2.) if not, would the 1125 be considered a "smoke Dragon"?

If so,

Erich, unless you live out in the sticks & don't need to worry about E.P.A. II rules, & your house is paid for, has anyone warned you that your Insurance Co., Town Hall, Fire Marshall, dog catcher, etc are not going to condone your Morso installation?

Best look into that matter before punching any holes in the house.
 
Be Green, great point, I didn't think of that. I will bring the class A deep into the room for that reason. That particular piece will be very short, so it shouldn't cost much to do that. If I use a 4 foot length, that will probably be about right. Going back to pictures, just so we're clear, according to the cartoon below, you are talking about increasing the dimension "A" right?

Dave, yes that stove is the same as mine, but not mine. The flue is 8", and I have an adapter to bring it down to the more normal 6", so all my stovepipe/chimney will be the standard size. And the sketch is not to scale, I drew it up quickly just to show what I had in mind. But, it would be about 5'5" high, maybe I should consider lowering where I wanted to go through the wall. Also Dave, this stove is temparary, I know that it's not the "best" stove due to it's age, but within a year or 2 I planned on upgrading to a new, more efficient stove. And yes I do live out in the sticks.


One more question regarding where the chimney penatrates the wall, I need to go through the wall AND the wall protectant. Should I do it like the left picture below, just leave a large hole in the wall protectant where the pipe goes through? In that picture the green represents unprotected sheetrock and the tan is the durock/ceramic tile protectant wall. The bottom of the square hole in the wall protectant will be high enough to meet spec from the stovetop, and remember I will carry the outside pipe into the room like dimension "A" I drew on the right side.
 

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I also want to thank you guys for putting in the time to help me on this.............I do not want to hire someone to install this.
 
Erich, not to worry about an old stove, mine turns 30 next year. ;-) Just check it out for weld damage by using a light bulb inside the stove. Burn wood as dry as you can get in the non creosote range, as indicated on a thermometer, & you will be fine.

HOW CAN I CONTROL CREOSOTE?

(broken link removed to http://www.cdc.gov/nasd/docs/d001001-d001100/d001052/d001052.html)

(broken link removed to http://www.northlineexpress.com/itemdesc.asp?ic=5CN-3-4&source=froogle&kw=5CN-3-4&source=froogle&kw=5CN-3-4&source=froogle&kw=5CN-3-4)

And though you live rural your insurance company needs to know about the stove as it can void your policy. Insurance companies do not like paying out claims despite their claims to the contrary.

As for:

One more question regarding where the chimney penatrates the wall, I need to go through the wall AND the wall protectant….”

Go back & see:

Installation 3 - Through The Wall

(broken link removed to http://www.woodstove.com/pages/prefab_chimney.html)

Next go to:

Class-A Chimney Typical Installations

(broken link removed to http://www.hartshearth.com/chimney/chimney_images.htm)

& look at their dwg for going thru the wall.

For info on insulated Wall Thimbles go to

(broken link removed to http://www.hartshearth.com/productcart/pc/viewcategories.asp?idCategory=40&pageStyle=M)

Once you have a good mental picture of this contact Hart at 800-924-0850 or

(broken link removed to http://www.hartshearth.com/Support_Request/Support-Form.html)

To confirm that your understanding is correct.

Good luck with it.
 
8" pipe all the way is what's required here. It's against code to downsize piping. See Craig's comments (#6) on pipe size in this thread: https://www.hearth.com/talk/threads/25498/

Also, keeping that horiz branch as short as possible is going to help draft. With a 4ft section of horiz. pipe on a choked down flue, it sounds like a smokey setup. Double-wall connector solves this issue.

If you're trying to save money, sell the stove for about $500 and apply that towards an Englander that can run with 6" all the way.
 
OK, So I can't go 8" down to 6", I'll believe that. But, if I install all 8" pipe, when the day comes that I want to upgrade to a new stove, is it up to code to go from a 6" outlet to a 8" chimney?
 
Yes, that is permissible.
 
You should, depending on the rec of your new stove maker, be able to go from 6" stovepipe into an 8" Class A chimney. That'll work in most situations. Downsizing from 8" to 6", as has already been pointed out, is a big no-no. Take it from somebody that's living with a Morso 1125, you want that 8" pipe all the way!
 
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