Legal to replace chimney (supported directly on) my Earth Stove 701/705 in old mobile home?

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Goldenvoice

New Member
Dec 28, 2021
2
NW Oregon
Hi everybody; new here, but not to heating with wood (been doing that since 1988). I have a dilemma, and will appreciate your thoughts.

My situation: when our old house decided it might slide into the creek, we bought a 1971 1350sq' double-wide "trailer house" for the property (cheap), which came with an Earth Stove 701ES / 705ES installed. That was 1998, and we're still here, and so is the stove. We've used it as our primary heat source through our NW Oregon winters. Last winter we had a couple flue fires after switching to Doug Fir, and so will, at minimum, go back to well seasoned oak & maple.

Anyway, we had the chimney inspected last spring, and were told it's seen too many flue fires, and is starting to come apart, so have not used it since. Sweep's recommendation was to drop to 6", but I've read that's not typically a good idea...

I guess the place to start is: is it legal to replace the chimney with the same set-up it's had since I don't know when? How might doing so affect our insurance?
*The install is class-A 8" from the stove's collar all the way up. I believe this was an approved method for these homes, as the ceiling/roof trusses are made of, well, basically 1x2 lumber, and I can't imagine it would like to support the weight of a chimney.

I called and spoke with someone at a local fireplace/stove shop, and was told flat out it's illegal to run class-A chimney directly off the stove (nowadays anyway)...

I will admit I've always been a little nervous about having a wood stove in a "trailer house", but as long as we've kept with hardwood, the flue has stayed relatively clean; only builds creosote (stage 3) at the cap and about 3" down the pipe. Also, the entire flue from stove to cap is, I believe, 9' - but she draws OK. It's twist-lock, like we've always called metalbestos. **Measures 10.25" inches OD** into a 10 5/16" collar (near as I can measure with the pipe in place)**

I'm not totally against purchasing a new stove, in part because it could move into a new home when it's time, but I'm guessing any "new" install would need the chimney support at the ceiling/roof level, in which case I'd have to do some real creative mojo to pull that off. It's also been a couple tough years for a working musician...

Thoughts? Joe
 
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I called and spoke with someone at a local fireplace/stove shop, and was told flat out it's illegal to run class-A chimney directly off the stove (nowadays anyway)...
That's the first time I've heard that. It's unusual, but done properly it should be safe. If money is tight then a new stove or more efficient stove with a 6" flue may be cost-effective. 6" chimney pipe is less costly and a more efficient stove will burn less wood. Most double-wides have at least 2x4 or 2x6 ceiling joists. Have you checked?

PS: It wasn't the doug fir that caused the chimney fire. Too cool flue temps are what did it. Often that is from burning poorly seasoned wood. Doug fir is good firewood, many of us have burned it for years. However, just like any other firewood, it needs to be fully seasoned and not smoldered.
 
Not sure of how your ceiling and roof are constructed, but one way of doing the roof install is to use a roof support bracket and trim collar below and run your chimney through that way. Can't imagine if your roof is designed for your snow load that it couldn't hold the insulated chimney. See video below:

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I would not install 6" on that stove. Some folks get lucky and the conditions are just right that it works. But I'd hate to buy all that material to find out it doesn't. Most of the mobile homes that I have seen are lucky if they can even get the minimum chimney heights. I agree with others that the roof should have no problem holding the chimney if properly installed. If it's a straight up install the stove will bear the weight whether it's double wall or class A. Most of the issues I have seen (especially in single wides) is folks skimp on proper clearances because of the space required. Does chimney replacement constitute requiring a permit and bringing everything up to code for inspection? Does Oregon require non-EPA stoves to be upgraded when work like this is performed? With the proper install I see no reason not to use double wall inside and class a from the ceiling up. Of course the price may not be much different than a new stove and 6" pipe. As for the wood, many of us burn lodgepole, for and tamarack without issue. The problem I see here in the NW is folks cut and sell wood in the fall. This is great if it's next year's wood but most are burning it fresh off the vine. Split stacked and covered, most soft woods will season properly in a year in our climate.
 
Concerning seasoned wood I'll add the caveat that I'm talking about wood that was cut dead. A lot of firewood in the west is cut off of some type of federal or state lands. In most cases the wood must be dead. In that case I have had good luck getting it to season in a year. I have cut green trees off of blow down areas and I leave it to season for 2 years.
 
Yes, I get my doug fir in spring, typically in March. It seasons well in our dry summers and by Nov. it is testing at around 17% internal moisture. I usually have wood left from the previous year to get me through a few chill chaser fires in Oct. I get less than a cup of soot a year when cleaning the flue.
 
Not sure of how your ceiling and roof are constructed, but one way of doing the roof install is to use a roof support bracket and trim collar below and run your chimney through that way. Can't imagine if your roof is designed for your snow load that it couldn't hold the insulated chimney. See video below:
Another option might be to use a cathedral ceiling support box supported by the roof.
 
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Thanks for the replies. Peering up through the peep holes around the shield, I'd say the trusses are made of 2x2 @ roof and ceiling, scabbed together with paneling left over from window and door cut-outs. And you're right: minimum chimney height probably wouldn't weigh all that much - the roof does support me walking around on it.

However, the distance from ceiling to roof is only 12", which doesn't give anything to combat horizontal forces (wind, etc). I'd want braces out onto the roof for that.

Permit: yes, it seems replacement of the chimney does require a mechanical permit by law, so to do it legally, I'd need to go that route. In this case, I actually like the fact it would need to pass inspection: I've always wondered if the current install was done "correctly"... It also seems an open-ended case of whether the permit issuer would let me move forward with a new chimney for this old stove. For that matter, perhaps they'd not let me put a new stove in this old trailer. I could not find anything truly definitive pouring through Google results for answers; maybe visit the courthouse?...

Local fireplace shop said they use an "installer" - perhaps that would be the person to talk to. The sweep I had out for inspection last spring, sadly, is out with health issues - I wish him the best.

Oh, and I've been suspicious about the Fir I was purchasing being a mixed bag (season-wise). I do now have a moisture meter, and will be more careful in the future.