ZC and Prefab - Need advice

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bbauer

New Member
Sep 26, 2015
5
Maryland
Hello all,

New user here and I've been looking over the threads to try and get as much information as I possible can.

In May, my wife and two daughters (ages 2 and 4) moved out of our townhome and into a single family a little more in the country of Maryland. It was a bank foreclosure that needed a face lift. We currently have 3.5 acres of property and about 2.75 of it is woods. Already had 3 oak trees drop in the woods this summer so wood is available. I've probably got 2+ cords already cut and stacked. Our house heats with oil and is approximately 2500 sq ft (two stories with a basement that wont be used much in the winter). Anyways, onto the fireplace.

The house has a zero clearance (majestic) and prefab chimney. The previous owners put in a gas insert. In order for the gas insert to fit in, they had to cut the ZC box. Also, they switched the chimney cap. The propane tank was taken by whoever leased it to the previous owners and I don't want a gas fireplace. period. So it has to come out and replaced

My #1 goal is heating efficiency/length of burn time. I'm nervous about what its going to cost me to heat the house with oil (even though oil is relatively inexpensive compared to what it has been in the past). My #2 goal is looks. This fireplace is in our main floor living room so am trying to make it look good. I am still keeping in the back of my mind resale value. My #3 goal is not spending a fortune. I'm still young and money doesn't grow on trees yet.

I had a local, large chimney/hearth company come out and look at everything (after I put a deposit down of almost $3,000). At first I wanted to install a wood burning insert. I went there mid summer and got the ball rolling. Took them a while to finally come out and tell me their final decision but I finally got it a few weeks ago. Was told wood burning insert wasn't an option b/c the ZC box has been tampered with too much and the insert was too hot for this. Does this seem legit given the pictures? Should I get a second opinion?

So onto plan B (which I have basically moved onto as well). They suggested a new high efficiency fireplace. The limited research I have done on these things makes me think they can put out some serious heat and could really help me on my heating bill. I was originally thinking a wood burning insert was going to cost me around $5,000 - $5,500 installed. After talking with the sales rep and him giving me the numbers for the Quadrafire 7100, replacement of ZC box pipe, labor, etc....he was thinking north of $7,500 at a minimum. This really made me wonder if all of this was even worth it.

After doing some research on here, I started thinking about a self standing stove in an alcove. Could I remove some of the lick and stick stone and set a self standing stove into it? My first concern was that my chase has 2 chimney pipes.....one for the oil furnace and another for my fireplace. Are they too close together for me to build out an alcove? Not 100% sure since this is a new idea I just realized I should consider. Side note, I think my wife would love this idea if done right. But nervous what this might cost

Then......my HVAC guy (who I have known my entire life and is a great guy, so I trust him) suggested a wood/oil furnace in the basement. My main concern here is can the existing piping handle a wood furnace? It's currently only handling an oil furnace which I know doesn't burn hot. Further.....if I spend around $7,000 to put one in....I still have an ugly ZC firebox upstairs that is cut up. Would probably need to spend some money here to fix it up.

So what would you suggest?



Questions:

- Any idea what kind of chimney pipe is currently in my pre fab chase? Class B - double wall? Will this need to be completely replaced if I go with a self standing stove or a high efficient ZC? Do I need Class A pipe for wood, period?
- Scratch the wood burning insert idea?
- Will the stonework need to be re done in order to fit a high efficient ZC fireplace?
- What would you estimate labor to be to install a high efficient ZC fireplace and new chimney pipe (in other words, how much do you think I need to tack onto the cost of my fireplace to get to a rough idea of what it will ultimately cost?)
- If I start thinking about the alcove......where do I start? Fireplace store or a general contactor? After looking at the pictures.....anyone have a rough cost on what it would be start to finish? $10k? Just trying to gauge if I want to even consider a project like this.
- Anyone have experience with wood/oil furnaces? Should I really consider this option for peak heating efficiency?

Thank you for any help you can provide! It is much appreciated.

Bryce
 

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Any idea what kind of chimney pipe is currently in my pre fab chase? Class B - double wall? Will this need to be completely replaced if I go with a self standing stove or a high efficient ZC? Do I need Class A pipe for wood, period?

Almost certainly, yes. Prefab chimney pipe is not rated for a woodstove/high-efficiency ZC fireplace.
Scratch the wood burning insert idea?

For sure. It is often debated here if it is a good idea to put one into a prefab fireplace that has not been messed around with. Once the prefab has been modified it would be completely unsafe.
- Will the stonework need to be re done in order to fit a high efficient ZC fireplace?

Depends. Would the fireplace/chase be accessible from the back? And you would need to find one that matches your current dimensions pretty closely.
What would you estimate labor to be to install a high efficient ZC fireplace and new chimney pipe (in other words, how much do you think I need to tack onto the cost of my fireplace to get to a rough idea of what it will ultimately cost?)

Ballpark $6000 to >$10000 total depending on the unit, labor cost, difficulty of install, chimney pipe required, etc. The Flame Monaco is a budget ZC which is compatible with many different chimney pipes. However, it will be undersized for your home if you want it as primary heater.
If I start thinking about the alcove......where do I start? Fireplace store or a general contactor? After looking at the pictures.....anyone have a rough cost on what it would be start to finish? $10k? Just trying to gauge if I want to even consider a project like this.

I would consider doing most of that yourself or you won't save a whole lot compared with a ZC fireplace. This thread has lots of pics to show you what to expect: https://www.hearth.com/talk/threads...ncy-zc-wood-burning-fireplace-project.114875/ The alcove can be finished by any general contractor. Make sure to decide first on a stove to stay within its clearance requirements. Check also if your oil boiler needs that long of a chimney or could be vented out the side.

Another option, not mentioned yet: You could maybe place a rear-vented stove in front of the fireplace and run a liner up your current chimney. That will be the cheapest option (~$4500 as a ballpark). Critical will be the depth of your hearth and the height of your fireplace opening to determine which models may fit.

Btw. Take your time. The oak you split this summer won't be dry enough for burning before next year's winter at the very earliest. Without dry wood there is really no need to rush into this project.
 
I ripped my ZC/insert out and installed a Blaze KIng wood stove in its place. It was a job but doable, just follow advice on here as there are plenty of old threads and knowledgeable people on here. I bought a used stove off craigslist and saved thousands upon thousands of dollars and now have a great setup.

https://www.hearth.com/talk/threads/blaze-king-install-help.110550/



Things I see: the mantel is low and would need to be moved higher in order to run a new ZC fireplace (I have one of those too).
The two pipes in one chimney is a no-no (I believe) in most states when one of those pipes is a wood burner. But call the city engineer to be sure.....
 
Almost certainly, yes. Prefab chimney pipe is not rated for a woodstove/high-efficiency ZC fireplace.


For sure. It is often debated here if it is a good idea to put one into a prefab fireplace that has not been messed around with. Once the prefab has been modified it would be completely unsafe.


Depends. Would the fireplace/chase be accessible from the back? And you would need to find one that matches your current dimensions pretty closely.


Ballpark $6000 to >$10000 total depending on the unit, labor cost, difficulty of install, chimney pipe required, etc. The Flame Monaco is a budget ZC which is compatible with many different chimney pipes. However, it will be undersized for your home if you want it as primary heater.


I would consider doing most of that yourself or you won't save a whole lot compared with a ZC fireplace. This thread has lots of pics to show you what to expect: https://www.hearth.com/talk/threads...ncy-zc-wood-burning-fireplace-project.114875/ The alcove can be finished by any general contractor. Make sure to decide first on a stove to stay within its clearance requirements. Check also if your oil boiler needs that long of a chimney or could be vented out the side.

Another option, not mentioned yet: You could maybe place a rear-vented stove in front of the fireplace and run a liner up your current chimney. That will be the cheapest option (~$4500 as a ballpark). Critical will be the depth of your hearth and the height of your fireplace opening to determine which models may fit.

Btw. Take your time. The oak you split this summer won't be dry enough for burning before next year's winter at the very earliest. Without dry wood there is really no need to rush into this project.

Thanks for the response.....this was helpful! Couple answers:

- The fireplace/chase would be accessible if we cut into the siding of the chimney. So I think I get what your saying....if we wanted to keep the stone in tact, we'd need to access the ZC fireplace from the back. Otherwise, demo stone work, put in the fireplace and then rebuild the lick and stick.
- I think I could do a lot of demo work on the alcove....not sure I'm ready to do the framing/finishing work. But I see how this could be expensive bringing in a contractor.
- Will try and figure out if my oil flue needs to run to the top of the chase. Would prefer to just have it piped out right at the base of my house (basement is underground on that side of the house).
- I'm not sure I could put a self standing stove right in front of the fireplace b/c there is only 28 inches from the lick and stick stone to the end of the hearth. Then the ZC fireplace is 6 inches further back. So I've only got 34 inches and I believe there is code about the front door of the fireplace must be 18 (?) inches from the end of the hearth, correct?

Thanks for the be patient comment.....I feel like I'm trying to rush this b/c I want to burn wood this winter. I split a lot of the wood in May and have left it stacked and uncovered in the sun....was hoping it would season quicker and I'd be able to burn it come December. Bad idea?

Thanks again,
Bryce
 
I ripped my ZC/insert out and installed a Blaze KIng wood stove in its place. It was a job but doable, just follow advice on here as there are plenty of old threads and knowledgeable people on here. I bought a used stove off craigslist and saved thousands upon thousands of dollars and now have a great setup.

https://www.hearth.com/talk/threads/blaze-king-install-help.110550/



Things I see: the mantel is low and would need to be moved higher in order to run a new ZC fireplace (I have one of those too).
The two pipes in one chimney is a no-no (I believe) in most states when one of those pipes is a wood burner. But call the city engineer to be sure.....

Thanks....I had thought about the mantle but the inspector didn't say anything when he came out originally. I will look into that. Definitely going to try and research about the two pipes issue. That could be a big issue if that is the case.

Bryce
 
- The fireplace/chase would be accessible if we cut into the siding of the chimney. So I think I get what your saying....if we wanted to keep the stone in tact, we'd need to access the ZC fireplace from the back. Otherwise, demo stone work, put in the fireplace and then rebuild the lick and stick.

Exactly.
- Will try and figure out if my oil flue needs to run to the top of the chase. Would prefer to just have it piped out right at the base of my house (basement is underground on that side of the house).

Moving the oil flue out will give you more room for a stove or a ZC fireplace. However, as long as oil burner and fireplace are vented in different flues it should be no problem having the two pipes in the same chase.
- I'm not sure I could put a self standing stove right in front of the fireplace b/c there is only 28 inches from the lick and stick stone to the end of the hearth. Then the ZC fireplace is 6 inches further back. So I've only got 34 inches and I believe there is code about the front door of the fireplace must be 18 (?) inches from the end of the hearth, correct?

Code is 18" in Canada and 16" in US unless the manual says something different. Your current hearth is pretty deep; a simple hearth extension may be enough to give you enough hearth clearance. http://www.woodlanddirect.com/Wood-Stove-and-Accessories/Hearth-Extensions (If your local building inspector and your home insurance agree with that solution.)
I split a lot of the wood in May and have left it stacked and uncovered in the sun....was hoping it would season quicker and I'd be able to burn it come December.

It depends on the wood species and your drying conditions if the wood is dry enough although 6 months is usually not enough. Buy a cheap moisture meter, take some random splits from different spots of your stack, split those in half and push the pins of the MM in the center of the fresh surface. The wood is ok with a moisture content below 20%.
 
So I'm really trying to figure out about (1) if I could put a self standing (rear vented) stove in front of ZC or (2) ideas for an alcove.

Couple questions:

1) Do clearance issues go away when you use stone as your siding in an alcove? So for example, if I created something like the link below with stone siding vs fire board/dry wall, would my clearance concerns go away or be significantly reduced? The reason I ask is b/c I'm not sure I can knock out all of my lick and stick given that I have another flue to right hand side of my current ZC box (for my oil furnace in the basement). So I'm thinking I'm going to have to keep it similar dimensions as my ZC box, but push it back a few inches. So basically exactly what you see in the link below, but not as wide (I think).
http://www.bowdensfireside.com/fireside-blog/fireplace-installation-millstone-nj

2) I was wrong about my hearth size....it's 20.5 inches plus about 7 inches back to the ZC. So call it 27 inches. So might be difficult to put a self standing stove there unless I did a hearth extension. Which that leads me to my next question. I have a raised hearth as you can see in the pics. Do people still put "hearth extensions" on the floor in front of a raised hearth? Is that what is in the link above? I was thinking something directly in front of the hearth (and not the entire length of it....maybe just two, 12x12 pieces of tile). I guess If I was able to put a 12 inch hearth extension, that would give me about 23 inches for a stove (assuming I can back it up straight up to the ZC box).
 
1) IF the manual says you can reduce clearance with a wall shield THEN you can get away with a smaller alcove. Look for example at the manual of the Jotul F45. In Fig. 12 (page 12) it shows the stove with ventilated wall shields in an alcove reducing side clearances to 6" each. However, just putting some stone over drywall is not a proper wall shield. For a ventilated wall shield you need something non-combustible (like cementboard with tile on top) spaced 1" from the wall with a 1" opening at the bottom and also open on the top. That way air can flow behind the wall shield and out the top and thereby cool the combustible wall. https://www.hearth.com/econtent/index.php/articles/stove_wall_clear

2) (Removable) Hearth extensions in front of the stove are usually fine as long as your local building inspector and your home insurance agree. What is your lintel height measured from the hearth? The rear flue outlet of the stove needs to clear the lintel or that solution won't work. The Quadrafire Explorer 2 ((broken link removed to http://www.quadrafire.com/Products/Explorer-II-Wood-Stove.aspx?page=Specifications)) has a leg span of less than 20" and a flue height of 29". If the height works that may fit. (Although I am not quite sure what you mean with 20.5" plus 7"; where are those 7" coming from?)
 
2) (Removable) Hearth extensions in front of the stove are usually fine as long as your local building inspector and your home insurance agree. What is your lintel height measured from the hearth? The rear flue outlet of the stove needs to clear the lintel or that solution won't work. The Quadrafire Explorer 2 ((broken link removed to http://www.quadrafire.com/Products/Explorer-II-Wood-Stove.aspx?page=Specifications)) has a leg span of less than 20" and a flue height of 29". If the height works that may fit. (Although I am not quite sure what you mean with 20.5" plus 7"; where are those 7" coming from?)

Sorry, that was probably confusing. If you look at the pictures above, you'll notice that my zero clearance box is set back a little bit. So I've got 20.5 inches from the end of the my hearth to the closest point of lick and stick. Then the lick and stick turns in and goes back another ~7 inches until it hits my ZC box. It's kind of hard to see in the pics. I think if you look at the one showing the cut in the ZC box, you can see on the sides of the pictures that it's set back a little. But now I'm worried b/c if I understand this correctly, I can't just shove a self standing stove into that existing cut out and run the pipe out.
 
Then the lick and stick turns in and goes back another ~7 inches until it hits my ZC box.

Just took a look again at teh 2nd pic and got it know. It depends how big that opening is to say whether a stove would fit or not. We will need all dimensions. This chart may help:
(broken link removed to http://www.woodheat.com/how-to-measure) Especially A and E will be important to know.

However, when you don't know what is behind the stone then you will have a hard time with clearances. Even double-wall pipe may not give you enough clearance to put a stove there. An alcove would certainly be the cleaner and safer installation.
 
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