I’ve got a house with no chimney, and I’m considering installing one made of fieldstone. The house had one (it was brick, with a fireplace, hearth, etc.), but I removed it so that the house could be raised while I installed a foundation. During the foundation work we installed a 12″ thick chimney footing with a #5 mat in it, which is what the engineer said was needed for a typical brick or stone chimney. The old brick chimney was built on a huge mound of fieldstone resting in the dirt, as was the house itself. Total height would be in the neighborhood of 18 feet. The goals are (1) aesthetics–there is a huge blank space on the side of the house where the brick chimney was, and (2) function–we want to install a freestanding propane stove where the hearth was and vent it through the new chimney (although yes, it could direct-vent or go into B-vent, etc., but I’m not doing exposed mechanical without a gun to my head). I’d like the thing to taper gently on all three sides along it’s entire height.
So, I’ve got the footing, I’ve got a huge pile of fieldstone (it’s mostly granite, mostly round river-rock in shape), and I’ve got more time than money. Everyone up and down the road has a stone pile too, so there’s stone to be had, and there are plenty of chimneys and walls around out of this exact stone. I spoke with one mason who suggested $10K as a price, and as much as I’d like to cut him loose on this thing I can’t justify parting with that kind of dough right now to have it done. I understand vaguely that a chimney in this situation would consist of a core of concrete block of some type (w/ rebar) and a veneer of stone. I do not know more than that, except to say that I would have the engineer detail the structure of this for the county permit department before proceeding. Bottom line question is, can a project like this be done hands-on by someone who is otherwise a seasoned remodeling contractor and journeyman carpenter but never done stone or masonry? Are there sufficient resources out there in print to back up such an adventure?
I’m also interested in aesthetic input from others and can post photos of the house (w/ brick and without) if there’s interest.
Replies
Maybe you could have a pro do the lining and block to get a safe, functioning chimney and do the decorative stone veneer at your leisure. I imagine most of the money in a job like that is the time required to work with the irregular shapes of the natural stone.
Al Mollitor, Sharon MA
Stonework is all about hard labor and persistence, particularly with hard stones that cannot be trimmed easily. Obviously, you will need really good staging. Depending upon the size of the stones, you may need some method of hoisting them into place up high.
Not the budget way, but renting some sort of mechanical lift, like a scissors or boom lift would be the low-exertion way to go. Heavy duty pump jacks might be a feasible slower/cheaper option. Some are rated for 2000lbs. They also have those 'ladder lifts', which are limited to the capacity of the ladder, I presume.
The trickiest thing with an exposed stone chimney has to be the flashing between chimney and house. Many historic homes around here have terrible problems when the lead eventually gives out. Brutal to repair with the irregular shapes of the stone.
Consider a heavy continuous membrane on the house top to bottom, perhaps with a drainage plane that you could butt the stones right up to. Membrane could be somewhat wider than chimney, then siding could extend over membrane. If you can avoid step flashing each stone, it will go at least twice as fast.
If you were to define the chimney edge with some sort of angle material, your siding end cuts could be straight, instead of scribed to fit. This would also give you something to mortar up to.
For efficiency, you could consider slip forming. Some slipforming links.
http://www.hollowtop.com/cls_html/stone_home.htm
http://www.hollowtop.com/cls_html/masonry.htm
Edited 11/10/2003 12:58:04 PM ET by csnow
David,
I am so glad you asked this question. I too would like to build a stone fireplace. I have heard estimates as high as $30,000 for what I am interested in.
I too think I could do it myself. You know strong back weak mind. I am not insulting masons here, just saying that my mind might be too dense to appreacite the extent of the job.
In your case it could be a simpler job in that you are only venting a gas unit. I think that is a simpler flue issue. On the other hand, you would want the flue to last since replacing it inside a 16 foot chimmney would be impossible, so you might still want to go clay.
Don't take any of the above as if it came from anyone who knows much of such things, just thinking out load and hoping others who do know will comment.
I really would like a source for the how to of stone laying. I would like to build a . . . probably 25 foot river rock fireplace in the middle of new construction. No stone cutting as it would be round river rock. It seems to me that the tricks would be, the art and patience of fitting the rocks togather, mixing mortar to the RIGHT dryness, and the knowledge of any underlaying steel or wire mess. And of course the details of flashing which an generous poster already mentioned.
Good Luck with your project and hope we get some responses here.
"I really would like a source for the how to of stone laying. I would like to build a . . . probably 25 foot river rock fireplace in the middle of new construction. No stone cutting as it would be round river rock. It seems to me that the tricks would be, the art and patience of fitting the rocks togather, mixing mortar to the RIGHT dryness, and the knowledge of any underlaying steel or wire mess. And of course the details of flashing which an generous poster already mentioned."
JR,
Much more to it in your case. Fireboxes, throats, and smoke shelves are tricky business. You may want to consider using a precast rumford throat and let someone else take care of the engineering for you.
Also, consider whether a "real" fireplace is what you really want. Let's face it- 'fake' inserts are much more efficent for woodburning, can be sealed tight when not in use, and consume outside air for combustion. SS flues heat up quickly, and draw better than massive masonry flues. One study showed ordinary wood fireplaces as having negative net efficiency. This is primarily because the flue cannot be closed until the fire is completely out. During that period, more heat is lost than the preceeding fire generated.
A sealed unit with glass doors that can be opened when you want to get 'primal' is the best of all worlds, IMHO. Then you can close the doors, go to bed, and forget about it...
If you really do want a 'real' fireplace, check out these links:
http://www.rumford.com/superiorclay/Todd.html
http://www.rumford.com/prod.html
Edited 11/10/2003 4:04:27 PM ET by csnow
csnow, all excellent points. I was considering using a totally prefabed firebox chimney deal, Isokern is the product. All pre-engineered, can be set up with outside air intakes for combustion, and the material is a pumise product which has a high insulation value and therefore the flue heats more rapidly.
My bigger concern, therefore, is the stone laying. Am I stupid for even thinking about doing it myself?
Nah. Go for it. Not technically demanding, just really hard work. Bet most of the old stone chimneys around here were put up by farmers, not stonemasons. Of course, they felled the trees, hand hewed the posts and beams, and everything else. They had much less technology available to them. No fancy staging, no Portland Cement, no concrete, no reinforcing mesh, no electric mixers, no hammer drills, no carbide, no dump trucks...
Probably did have some sort of draft animal for the hoisting part, from what I have read.
Do your own cost/benefit analysis. Perhaps a time/money analysis as well...
Edited 11/11/2003 9:01:53 AM ET by csnow
Like you I am a carpenter that has done some masonry work. Have you ever tried to stack some bowling balls? River rock ain't easy.
You would at least need a good mason to get you started, or maybe you could be the helper and save some money. The firebox is tricky, as are a good few other parts. The brick or rock is a veneer. The part that holds smoke is special clay blocks or stainless snap-lock pipe sections. The core is only lightly supported sideways by the veneer and there is an air gap between them. The core expands from the heat and the veneer does not. There's a ton of work erecting scafolding, mixing mortar and carying stone. The firebox and hearth are special firebrick, not regular brick. If you did all the grunt work, maybe you could find a mason who would be willing to do the part that takes more skill. I've seen it done many times. $10K is very cheap for a fieldstone job. A couple weeks work if it looks decent.
On the other hand, if you bought a prefab steel firebox and used stainless chimney pipe, all you have to do is the veneer part. Still not easy, but you might have a fighting chance as a DIY project. The downside is that the firebox and pipe is easy a couple or 3 thousand. The plus side is that it lasts well and is safe. Even for fieldstone, you'll have a good thousand or two for mortar, firebrick, chimney block, mantle, etc.
The more masonary I do, the more respect I have for real masons. The first three walls I did are within sight of each other (at my folks') and it is very clear which was my first, my second and my third. The third one is pretty straight, plumb and even. Not so, the first.
Those little retrospective epiphanies that you have during a project? That you are used to fixing the Sawsall? With masonary, you will have memorialized them forever "in stone", literally.
I would strongly suggest you do a "retaining" wall of no great height, a planter bed and/or a BBQ as a trial run. Compare the cubic yards and tons involved to the proposed chimney and assess if you want to invest that much time, Advil and discs in your back into the project. You will then be going into the project with your eyes open and definitely with a better set of basic masonary skills.
I second David Thomas's suggestion. Build something small first. You can experiment with different styles and techniques and will find out whether this is for you. I veneered a 4'x60' retaining wall last year and am pretty happy with the result. Possibly my next project will be a chimney. I will have a mason lay the firebox and block core.
BTW- 10k is a pretty good price if the work is what you want.
This may not be appropriate; but, I've seen a number of fake chimneys (i.e. ply structure with veneer of stone/brick on them) that hide modern gas venting.
Phill Giles
The Unionville Woodwright
Unionville, Ontario
for a free standing propane stove you would not necesarily have the same fire and heat associated with a wood stove. I think you could build a masonry chimney. You could get Chimney block w/ a clay tile flue liner. The Chimney blocks are easy to lay if your careful and have scaffolding. The flue liner uses a special ready mix mortar available from Masonry outlets.
You could lay in wall ties to the joints that will help attach your stones. I like stacked stone work, as apposed to veneer. I've been using small flat creek stones, around 1/2 to 2 inch think, 4-5 inches wide, and the longer the better. Occaisionally I throw in a big rock, than work around it. I hide all the mortar, as best I can, in the back of the rocks. You get this dry stack look, which I like.
If your a carpenter and remodeler and you have some block laying skills I'd say do it.
Laying stones is ancient, everyone I ever know to do it has some kind of reverence for the space it puts you in.
The house I grew up in had a large river rock fireplace. Most of the rocks were nearly round or oval. The problem was that it didn't take that much to disloge some of the rocks. (I think the house was probably about 30 years old when we moved in). I have always wanted such a fireplace, but figured if I did, I would have to figure out a better way to anchor rocks than just sticking smooth round rocks into traditional mortar. What's the solution? Epoxy a tab on the back, drill and insert a small rebar into the back of each one, rough up the surface on the back for better adhesion?
A couple of good books to take a look at. The Art and Craft of Stonework by David Reed and Building With Stone by Charles McRaven (has an entire chapter devoted to building a stone chimney)
Casey, I have had the same question or concern about river rock.
I hope someone can address it. However, it does not appear that this forum has many stone masons in attendance.
Sounds tough,
Round smooth surface veneered to a vertical surface. I've seen the look and it is very impressive. I'm sure there are lots of ways to do it, mostly labor intensive as you have described.
Nevertheless it sort of goes against the laws of gravity. And in the end gravity wins.
I would personally try to stick with a stacked rock approach, I like the look and it is self supportive. It holds itself up and so needs less tension to hold itself to the vertical surface.
What's the solution? Epoxy a tab on the back, drill and insert a small rebar into the back of each one, rough up the surface on the back for better adhesion?
Yikes. Drill or grind every stone? That would take forever and a day. Modern mortar mixed properly is strong stuff. I suppose it depends upon how much of the stone is embedded, and how well it is supported. Corners tend to be vulnerable. Choice of stone is very important in corners. There is a tendency to rely completely upon mortar now, but an inherently more durable design has the stones supporting each other. You can use a bonding agent to improve adhesion.
No doubt that thin flat stones are much easier to work with. They stack easily, and can be cut.
Fieldstone is generally rough enough for the mortar to get good bite. I suppose it depends somewhat upon where you live. In New England, fieldstone tends to be hard igneous stuff. Traditionally, small stone wedges were used to support the larger stones. I was told that in my region, the stone broken up for small wedges was often brought in for that purpose, since they needed something that fractured easily to make the wedges from. Probably a sedimentary rock. These structures were quite stable when dry. The mortar was only there to keep things from shifting. Also to keep out drafts and pests for walls...
Laying the stone veneer is easily in your range. I started out hoddying/laying brick for a guy who was really good and we did stone jobs occasionally. It's more of an art than a craft and much more forgiving of mistakes than brick.
Buy a used concrete mixer. You'll kill yourself mixing that much mortar in a wheelbarrow. Look at some good stone work. To me, the less mortar the better a job that was done. Anybody can lay stone on 3" mortar beds.
remodeler
remodler, does your "go for it" advice include smooth river rock. On the one hand, it would seem that it would be easier since there is no cutting and trimming involved. On the other hand the issue of adhesion has been raised.
The actual placing of the stone to get uniform spacing would be all eye and art. I think I have the eye and patience for that.
If one wanted to build a floor to ceiling fireplace in a greatroom with 18 foot ceilings and perhaps another 4 or 5 feet through the roof, are there reinforcing issues? Any books on the subject?
The one-on-two two-on-one comment is a great one, as well as using reinforcing wire. I disagree with the hire-a-professional mason comments down the line, though.
Only if you find a good one. I have been around masons a lot of my life. Many know s**t about good firebox design. They are accustomed to the builder-style inefficient and smoky fireplaces all of the production builders put in. You mention being competent in other trades and IMHO you can probably do a better job with time & patience on the firebox than someone you hire.
The guy I started laying brick for when I was young did a 5th grade book report on Rumford fireplaces. He lived and breathed masony and did wonderful quions, arches, built-ins, etc. Many masons these days - from visual observation - have trouble laying even head & bed joints, and the only guys I see lining head joints up are the union masons in my town on commercial projects.
Masonry is based on gravity. That's about the only thing holding it together, low coefficient of adhesion between stone/brick/etc and mortar. So it doesn't matter the stones are round, you might find a limit to courses you can lay between setting the mortar up to keep the weight from deforming previous courses. River rock makes beautiful fireplaces.
remodeler - good luck
Thanks for all of the very thoughtful replies on this one. Quite a bit of discussion has been on firebox and smoke chamber stuff, which I do not believe applies to my project. All I need to do mechanically is to vent a propane stove. This isn't a woodburning fireplace project, in fact, from the inside there will be no evidence of the chimney.
I definitely agree with the build-a-wall-or-planter-box-first advice, because a test run is always good. The problem is that I've got nowhere to do that--no soil to retain on the property, and the wife doesn't want a stone planter. I'm in the process of identifying the few masons there are here, and if I find one amenable to using me as a helper, that may be the way to do it.
I agree with a couple of the others, here. Find a mason who is easy going and hire him to build the most technically demanding parts. Mainly the core of the chimney, meaning the firebox, smoke chamber and at very least, the lower section of flue. You should be there with him and watch, possibly even help as a laborer. Then have him start the stone laying process to show you the basics. Ask if he would be available to return when you need to install the flashings where roof connections occur. Then have at it. Without a doubt, the most expensive part of the project is the stonework. More importantly, without a doubt, the part you as an amateur are most likely to goof is the firebox and smoke chamber.
carpenter in transition
David,
Wrap your substructure with some 4" or 6" welded mesh.
Soak the stones in water for 5 or more mins before laying them.
Get a P/U load of 1 1/2" and down crushed rock.
Use the CR as shims to dry set each stone so the stone is stable, then remove the stone and set your mortar and replace the stone the same as it was dryset.
Use heavy tie wire tied to the welded mesh ran into the mortar wherever possible. Kink or loop the tie wire to provide a good bond to the mortar.
Oh, before I forget, pick up a couple bottles of Aleve or something (|;>)
SamT
I'm not a stonemason, but I've built two river rock/fieldstone (i.e., round cobblestone) fireplaces, faced several others, and have repaired lots of old stonework. I'm about to begin construction of my third, for which I'm using the Buckley/Rumford/Superior Clay pre=case throat and smoke chamber. Check the Buckley web-site for tons of useful information, including references to the operative codes for masonry fireplaces/chimneys.
Several suggestions: first, establish your corners with framing lumber (outside the edges, obviously), which you can then use to screw/nail furring strips across to support the stones as you go up. This will give you straight edges and a way to support the stone until the mortar sets. Use a mortar that's got a substantial portland cement component. I've previously just made my mix 1 Portland, 1 Mortar, six sand. Believe me, concrete is sticky stuff, and will hold your chimney together just fine after it sets. The problem is keeping it all in place until it sets. I built my first fireplace with a concrete block core, covering a firebrick rumford box, common brick/ refractory cement parged smoke chamber, and 12x12 refractory flues. The next time I didn't bother with the concrete block: stone is a real building material, it doesn't need an artificial one to lean against. Once the edges are established its easier to fit the stone without the further obstacle of a concrete block inside leaving only a limited, fixed distance to work. Obviously the flue liner (and the required expansion space around it) are a fixed limit; but you'll have alot more breathing space if you just build with stone.
Always remember the golden rule of stone laying, even with round stone: one on two, two on one. Minimize the amount of concrete sticking out: you want a stone chimney held together with mortar, not a concrete chimney with some rocks swimming around in it. Mostly its a weight lifting project You can do it, it ain't magic. Good luck.