Advice Needed: Our First Home Has a Zero Clearance Fireplace - Options?

[CJRages]

Hi all,

A newbie here...I have done some research here and on other websites, but I haven't found an explanation that exactly fits our situation... so here it goes...

My wife and I purchased our first home one month ago. The house is a split foyer built in 1979. Upstairs 1,350 square feet and basement 650 square feet + garage. Our zero clearance - prefab fireplace - is located in the basement and had a very large wood burning insert placed in it (earth stove brand - appears to be from the 80's?). The fireplace is vented through a chase running up outside the wall of the home containing an 8 inch single wall pipe. We had an inspector take a look. He greatly frowned upon the setup >:-( (not surprisingly after what I've read) exclaiming how dangerous this type of situation can be. The same inspection company had been hired in 2002 and failed the system then as well. From what he could tell the stove has hardly been used - gasket still in good shape - no warped metal door - hinges are not heavily worn. So hopefully the previous owners took some caution.

We would like to install a wood burning system that would heat at least 75% of the house (or approx 1500 sf). We plan to sell the monstrous Earth Stove insert. What are our options here? I have looked at various "zero clearance approved inserts" and have a short list of 4-5 stoves that would fit in the fireplace and still meet clearance requirements. How does that affect our liability for insurance purposes? I understand that zero clearance fireplaces are not tested for use with wood burning inserts.

I appreciate anyone willing to help shed some light on this. I know there are many experts here that have come across this many times.

Thanks in advance.
-Chris

 

[Pagey]

Is the basement finished and insulated?

 

[CJRages]

Yes. The basement is finished. It appears to be insulated as well. only 1/2 of the lower level is underground and has a walkout on one side of the home. There is definitely insulation on the above ground level of the basement. From measurements that I have taken it appears that the lower 1/2 of the walls are at least somewhat insulated as well. It has super nice wood paneling instead of drywall... lol.

 

[Pagey]

I think you're going to find one of the most interesting dichotomies I've ever witnessed in the wood burning world. Some installers and dealers will chime in, but it's my understanding that though there are "zero clearance approved" inserts, no ZC fireplace is actually approved for a wood burning insert.

Hopefully someone will correct me if I am wrong, but I recall a pretty lengthy thread on here where a guy was trying to find out what insert to use in his ZC fireplace. Seems that though there are several ZC approved inserts out there, no ZC fireplace is technically approved to accept inserts.

Assuming you go with an insert, you'll want to get rid of the single wall and go with a UL103 HT rated double wall pipe sized appropriately for the flue collar on the insert you choose. Or you may find yourself happier with a free standing stove upstairs on the main level of the home.

 

[CJRages]

Thanks Pagey.

Do you have any thoughts about installing an insulated ss liner to connect with a zero clearance approved wood burning insert? Is it safe or would it be much better to replace the existing pipe?

 

[LLigetfa]

I'm confused. I understand that "an 8 inch single wall pipe" is unsafe but what part of the insert is brought into question. First off, isn't zero clearance insert an oxymoron? I guess it is at least ambiguous. Most people call something that you slip into an existing masonry hearth an "insert". Obviously those need not be "zero clearance".

I have a real zero clearance insert meant to be inserted into an opening that can be framed with combustible material. I chose to use metal studs and cement board/drywall where appropriate I chased the chimney with radiation shield the length of the second story for additional peace of mind. There is nothing unsafe about it.

Replace the single wall pipe with a proper chimney. If there are clearance concerns, chase the length with radiation shield. If you cannot do this without disturbing the fireplace or you want a newer better wood burner then ja, replace it too.

 

[Pagey]

Many people with an existing masonry chimney use stainless steel liners and have great results. In order to reach the UL1777 listing, the SS liner requires insulation (again, if my memory is working). I don't think any/most of the ZC fireplaces use Class A pipe rated to UL103 HT. Some are rated for 1700F, but the HT rating gets you to 2100F.

 

[polaris]

Jotul freestanding stoves and inserts(most of them anyway) are rated for connection through a zero clerance fireplace. They do however need to be lined to bring the temp rating from 1700 to 2100 as was previously mentioned. There are other brands approved for ZC install as well but I don't remember which ones off the top of my head. I installed a Jotul Castine through a ZC and it is working well. I did reline the chimney and extend the hearth though. So it can be done safely and pass an inspection but it involves a bit more than just running the stove or insert through the ZC as it is in it's original form. What you end up with is a 2100 liner surrounded by an air cooled pipe wrapped by the 3rd or outer pipe.

 

[CJRages]

Very interesting Polaris....

I'm hoping the liner + air cooled pipe + outer pipe setup would work for us. How cost effective is that versus something such as what Pagey proposed earlier (tear out old pipe and install an UL103 HT double-wall pipe? Also why did you have to extend the hearth?

Just as a reminder, the current chimney is an 8 inch pipe enclosed within a wood framed, sided chase. There's really nothing masonary about the chimney allthough the hearth is brick.

 

[tickbitty]

I am by no means an expert, but I've been poring over a pdf of a Lopi insert manual for a little while and on the front page it reads "Masonry fireplace insert" AND "Zero Clearance (metal) fireplace insert"

I'd be willing to bet if this brand works a lot of the other current models do as well. Or are the zero clearance fireplaces different types?

 

[Pagey]

According to Lopi's site, the 1750 insert is approved for installation into a ZC/metal fireplace. (broken link removed to http://www.lopistoves.com/productuide/detail.aspx?id=303)

Is your existing chimney a masonry chimney?

 

[fredarm]

All 3 sizes of Pacific Energy inserts are approved for installation in ZC fireplaces.

 

[CJRages]

It is very exciting to see how many manufacturers there are that produce zero clearance rated wood burning inserts.

According to Lopi's site, the 1750 insert is approved for installation into a ZC/metal fireplace. (broken link removed to http://www.lopistoves.com/productuide/detail.aspx?id=303)

Is your existing chimney a masonry chimney?

No. Unfortunately it is not. See my last post above.


Anyone else have a take on an approved and safe way to vent one of these stoves through a prefab - zero clearance - fireplace and 8 in metal single wall flue/chimney?

 

[Pagey]

I'm sure an installer will chime in. Can you run 6" SS liners down an 8" ZC pipe and meet code/UL listings folks? I'm clueless there.

 

[CJRages]

Here's a bit of insight I was able to locate from a pacific energy insert installation manual for the for zero clearance/prefab requirements.

Into a Factory Built Fireplace
Your Pacific Insert may be installed into a factory built
fireplace with the following requirements:
1) Inspect your fireplace for damage or other physical
defects. The fireplace must be in good working condition.
If in doubt about its condition, seek professional advice.
Check for creosote build up or other obstructions inside
the chimney, especially if it has not been in use for some
time. Before installing, clean your chimney system
thoroughly.
2) A full stainless steel rigid or flexible flue liner meeting
type HT requirements (2100°F) per UL1777(U.S.) or
ULC S635 (Canada) must be used for both safety and
performance. The liner must be securely attached to
the insert flue collar and the chimney top.
3) The surround must be sealed to the fireplace front or the
damper area around the chimney liner must be sealed
to prevent room air entering the chimney cavity of the
fireplace.
4) The air flow within and around the fireplace must not be
altered by the installation of the Insert (i.e. no blockage of
louvers or cooling air inlet or outlet ports). This includes
the circulating air chambers in a steel fireplace or metal
heat circulator.
5) Alteration of the fireplace in any manner is not permitted
with the following exceptions:
a: external trim pieces which do not affect the operation
of the fireplace may be removed and stored on or within
the fireplace for re-assembly if the Insert is removed.
b: the chimney damper may be removed to install the
liner.

Is it that simple?
Let me know what you think.

 

[Pagey]

The question, for me, is not whether or not you can use an approved SS liner to vent the appliance you choose to install. You clearly can. My question, however, as I've never seen this done/answered, is can you run the liner down an existing ZC 8" pipe? Did I use enough commas?

 

[basswidow]

We looked into getting an insert for our zero clearance Heatilator fireplace. What we found was that (even though we had one of the largest heatilators) the inserts that would work in it (i think there was only 1)- we considered to be too small for what we wanted. We also were concerned that the flue would have to be lined anyway.

We then thought of using a insulated liner and placing a free standing stove on a hearth pad, but again the clearances and finding the right rear discharging stove that the pipe was low enough - was also difficult - even using heat shields and lower feet.

We opted for removing the heatilator and the double walled pipe - which was not rated for the heat of a stove, and installed a class A chimney / flue in the chase with a Kozyheat Z42 fireplace. Overall - it cost around $ 5000 to include the fireplace, chimney and install. We are very happy with it. We have a 3700 sf home and it heats all of it - (not including the basement) and the room over the garage. It has a quiet blower and is basically a woodstove fireplace. I highly recommend them or the RSV Opel?

These are a simple exchange for a zero clearance and if you are handy - it's easy to do alot of the work yourself. I did my tear out and framing, also the finishing after install to save money. A kozyheat z42 would easily hear your home - no problem.

Or you could tear it all out and install Class A chimney and make an alcove with wood stove - as long as the clearances are good.

You can use an insert - but you still have to use an approved liner and - the insert is gonna be small.

 

[3dogsrule]

I'm following this tread closely, I had a similar thread going. When I built my house it is my understanding that they installed triple wall pipe, but my problem has been getting something approved to go in my ZC, which I was shooting for a stove that butts up to or slightly receeds into my ZC, but have been having trouble finding something that'll put out some heat yet isn't too deep (shallow hearth). BTW, I looked in my install manual for my Heatilator ZC, and under Problems, "Not getting enough heat from fireplace", one of the the causes is "unrealistic expectations"...I thought that was funny. Yeah, I unrealistically expected a fireplace to produce heat! Duh!! Anyway, removing my Heatilator isn't an option ($$$), but I sure am growing inexplicably tired of searching for a solution.

Karen

 

[thechimneysweep]

My question, however, as I’ve never seen this done/answered, is can you run the liner down an existing ZC 8” pipe?

Yes, but only if the existing pipe is double-or triple-wall ZC chimney. I'd go pop the cap and double check before proceeding, because if the folks who have told you your fireplace is venting into single-wall pipe are correct, the existing installation is in violation of code, and dangerous to boot.

Here's what you've gotta do, step by step:

1) Determine that the manufacturer of your ZC doesn't forbid installation of an insert. To identify your manufacturer, look just inside the opening, on the right side (facing), up near the top. Google the owner's manual, and read all the fine print. If you've got an FMI, for example, you're out of luck. FMI does not allow installation of wood inserts.

2) Determine that you have ZC chimney, NOT single wall. If you have single wall, tear the whole installation out.

3) Choose an insert that is specifically approved for installation in ZC fireplaces. As mentioned above, PE and Lopi inserts are approved for this application. Hearthstone and Avalon inserts are also listed for ZC installations, as are several others.

4) When you install the insert, install a stainless liner to the top of the chimney, because even code-approved double or triple wall ZC chimney doesn't meet the HT standard (that's what the quote from PE's manual above is all about).

 

[Pagey]

My question, however, as I’ve never seen this done/answered, is can you run the liner down an existing ZC 8” pipe?

Yes! You not only can, but are required to by most insert manufacturers. That's what the quote from PE's manual above is all about.

Very good to know! Thanks, Tom!

 

[LLigetfa]

Thanks Pagey.

Do you have any thoughts about installing an insulated ss liner to connect with a zero clearance approved wood burning insert? Is it safe or would it be much better to replace the existing pipe?

I don't think the existing single wall pipe is UL approved or to code. A flue liner is meant to go into a chimney that in and of itself already meets some code, perhaps just not the 2100 degree rating. Putting a liner inside the single wall pipe would obviously be an improvement but it might not satisfy your insurance company.

I'm still confused about the insert. Are you intending on installing an insert into the existing zero clearance insert?

 

[Wet1]

I think if I were going to do it, I'd install the 6" SS liner inside the 8" existing pipe and fill the void with perlite or vermiculite.

 

[CJRages]

Thanks Pagey.

Do you have any thoughts about installing an insulated ss liner to connect with a zero clearance approved wood burning insert? Is it safe or would it be much better to replace the existing pipe?

I don't think the existing single wall pipe is UL approved or to code. A flue liner is meant to go into a chimney that in and of itself already meets some code, perhaps just not the 2100 degree rating. Putting a liner inside the single wall pipe would obviously be an improvement but it might not satisfy your insurance company.

I'm still confused about the insert. Are you intending on installing an insert into the existing zero clearance insert?

LLigetfa,

My hope is to install a wood burning insert that is rated to be used within an existing zero clearance (a.k.a. prefab) fireplace. My fireplace is large enough to accommodate several qualifying wood burning insert models. The current set-up is vented by a single 8 inch pipe which does not meet code requirements. Apparently the remedy here is a 1777 approved stainless steel liner.

Now, on to the next part? :coolsmile:

Should I insulate the ss liner? I would feel more comfortable doing this. And for a couple hundred bucks the peace of mind would be well worth it. Any thoughts?

 

[Pagey]

I think the confusion lies within your first post: from reading, it sounds as though you already have an old 80s model wood burning insert in the ZC fireplace. Is that the case? Are you removing this 80s model insert and getting a new one? Or are you saying "insert" meaning "fireplace"?

 

[3dogsrule]

A stove I'm looking at requires, for prefab chimneys, to be tested to UL103 high temp specs. Would one be reasonably safe to assume that with 8" double-wall and a 6" SS liner, that one would be able to achieve those high temp standards?? Or would it take more than that?

Karen