DIYing a masonry heater in a circa 1880s home

[DIYMasonryHeater25]

I have known about masonry heaters for years, since I went to a B&B in Canada that had a large one in a main living area with a vaulted ceiling. I always thought it would be a good idea to have one in a home someday.

We purchased an older home (circa 1880s) in NE Connecticut , and have been renovating it, room by room, system by system. The oil tank and 50+ year old boiler were replaced by a heat pump (air to water...so the old radiators were taken out, and new ones were put in.) It works great....unless we lose power, or we fall below 10-15F.

There were a few woodstoves left in the house (it was an estate sale), and the only one that was fully installed was taken out due to the home insurance being iffy about having woodstoves. Now we need a backup heater...and instead of going through the woodstove process, I would like to DIY a masonry heater.

I already spoke to the building inspector, and he okayed me DIYing it instead of hiring a professional, but he would like to see the final design first (We don't have the 10-15k+ that they would cost, installed.) So, I am watching videos multiple times a week to understand the ins and outs of them, things to avoid, what is necessary, etc. Most are DIY videos, but I have seen a few pros and others utilizing a kit purchased from a pro. And I won't be able to start this until the kitchen is done...so I will probably start in May or June. I will be doing this after work and on weekends. (Probably on my own...my husband isn't enthralled by this idea. And he hasn't heard most of the plan yet.)

The house is in a rural area and has 2 floors (approximately 2,400 sf) plus a full basement, with fieldstone walls and poured cement floors. Since these are heavy, I would need to figure out how to support a 1000-1500 lb brick masonry heater on an old wood floor.....or build the masonry heater in the basement, and open up the living/dining room floor between joists, so the heater's bricks continue going up, totaling approximately 15-16 feet. There is an opening in the chimney on the first floor (about 5' off of the floor), but I think the design which sends the heat up the center with channels made of extra bricks to add mass, and the cooled air is returned on the outside's left and right sides, or on the back (downdraft design) may work better for us, and we can utilize the opening for the previous oil boiler on the same chimney in the basement. (I know the chimney liner would need to be changed.) This would hopefully heat up both the basement and the first floor. (The second floor's stairwell is off of the living room, so some heat would rise to the second floor as well, unless we do a redesign to close that off a bit.) And the firebox and any clean out points would be in the basement. I might need to add something on the second floor for cleaning out or bringing in air.

I know the firebox needs to be lined with, if not made from, fire bricks, and there are certain types of bricks to purchase for the rest of the design. I haven't thought about whether we would cover the exposed bricks on the first floor, as there is already a bricked section where the unconnected woodstove sits, next to the bricked chimney. The only issue is how much would have to be exposed 'on' the first floor to generate heat there. I would like to utilize that for us and the animals to curl up next to it, and if it gets hot enough, space to lay a tea kettle for tea or shallow pan filled with water for humidification on top. I am only 5'2", so I am thinking the top could be set around eye level. But if that isn't the best design or feasible, I would be willing to have a height of 6-7' above the living/dining room floor.

The biggest hurdle (other than considering going through the first floor) is making sure the floor (whichever it is) is reinforced enough for the total weight. I think the basement floor is only 2" of concrete, as it has cracked in some areas. Is there a calculator for how much of a concrete base we would need to add in the basement for a certain weight? I know it could raise it a few inches at least. And if I opt for putting the masonry heater only on the first floor, I would need to get steel supports for under that space, as it floods slightly (no more than an inch or so) a few times a year during the spring and early summer. Guessing I would still have to create a concrete base in the basement. But I just saw a video by Temp cast that used cinder blocks (3-5 rows) to support the masonry heater

If anyone has done this before, I'd love to know. See if there was anything I missed, design tips, etc?

 

[Todd]

If your looking for a smaller masonry heater just to help out these guys have some 1000 lb units you can easily put together yourself.

Kube - Norskkleber AS ENG

The Kube stove has classic clean lines, with a number of elegant features, such as the side windows that fit neatly in the stones without a steel frame.

www.norskkleber.no

If your looking into something that will heat the whole house your going to have to go bigger and it would probably be best to consult an engineer to address that 2” concrete in your basement. That may have to be beefed up then cement blocks all the way to your main floor then cutting the floor and pouring a slab. I don’t think you can just brace the main floor up with beams to support so much weight.

 

[bholler]

I have known about masonry heaters for years, since I went to a B&B in Canada that had a large one in a main living area with a vaulted ceiling. I always thought it would be a good idea to have one in a home someday.

We purchased an older home (circa 1880s) in NE Connecticut , and have been renovating it, room by room, system by system. The oil tank and 50+ year old boiler were replaced by a heat pump (air to water...so the old radiators were taken out, and new ones were put in.) It works great....unless we lose power, or we fall below 10-15F.

There were a few woodstoves left in the house (it was an estate sale), and the only one that was fully installed was taken out due to the home insurance being iffy about having woodstoves. Now we need a backup heater...and instead of going through the woodstove process, I would like to DIY a masonry heater.

I already spoke to the building inspector, and he okayed me DIYing it instead of hiring a professional, but he would like to see the final design first (We don't have the 10-15k+ that they would cost, installed.) So, I am watching videos multiple times a week to understand the ins and outs of them, things to avoid, what is necessary, etc. Most are DIY videos, but I have seen a few pros and others utilizing a kit purchased from a pro. And I won't be able to start this until the kitchen is done...so I will probably start in May or June. I will be doing this after work and on weekends. (Probably on my own...my husband isn't enthralled by this idea. And he hasn't heard most of the plan yet.)

The house is in a rural area and has 2 floors (approximately 2,400 sf) plus a full basement, with fieldstone walls and poured cement floors. Since these are heavy, I would need to figure out how to support a 1000-1500 lb brick masonry heater on an old wood floor.....or build the masonry heater in the basement, and open up the living/dining room floor between joists, so the heater's bricks continue going up, totaling approximately 15-16 feet. There is an opening in the chimney on the first floor (about 5' off of the floor), but I think the design which sends the heat up the center with channels made of extra bricks to add mass, and the cooled air is returned on the outside's left and right sides, or on the back (downdraft design) may work better for us, and we can utilize the opening for the previous oil boiler on the same chimney in the basement. (I know the chimney liner would need to be changed.) This would hopefully heat up both the basement and the first floor. (The second floor's stairwell is off of the living room, so some heat would rise to the second floor as well, unless we do a redesign to close that off a bit.) And the firebox and any clean out points would be in the basement. I might need to add something on the second floor for cleaning out or bringing in air.

I know the firebox needs to be lined with, if not made from, fire bricks, and there are certain types of bricks to purchase for the rest of the design. I haven't thought about whether we would cover the exposed bricks on the first floor, as there is already a bricked section where the unconnected woodstove sits, next to the bricked chimney. The only issue is how much would have to be exposed 'on' the first floor to generate heat there. I would like to utilize that for us and the animals to curl up next to it, and if it gets hot enough, space to lay a tea kettle for tea or shallow pan filled with water for humidification on top. I am only 5'2", so I am thinking the top could be set around eye level. But if that isn't the best design or feasible, I would be willing to have a height of 6-7' above the living/dining room floor.

The biggest hurdle (other than considering going through the first floor) is making sure the floor (whichever it is) is reinforced enough for the total weight. I think the basement floor is only 2" of concrete, as it has cracked in some areas. Is there a calculator for how much of a concrete base we would need to add in the basement for a certain weight? I know it could raise it a few inches at least. And if I opt for putting the masonry heater only on the first floor, I would need to get steel supports for under that space, as it floods slightly (no more than an inch or so) a few times a year during the spring and early summer. Guessing I would still have to create a concrete base in the basement. But I just saw a video by Temp cast that used cinder blocks (3-5 rows) to support the masonry heater

If anyone has done this before, I'd love to know. See if there was anything I missed, design tips, etc?

Have you ever done any masonry work before? What level of diy skill do you have? 2" is definitely not enough you will need to remove it and pour a proper foundation for this

 

[EbS-P]

1000-1500 lb brick masonry heater

First off this is really light. Only 2x3 times heavier than a big stove.

Have you found plans? I would never attempt to engineer a fire inside my house on my own.

There are really nice stoves. A Blaze King almost as good as a masonry heater IMO.

 

[qwee]

It just so happens the Masonry Heater Association (MHA) is having their yearly get together, Wildacres, in April at Little Switzerland, NC https://members.mha-net.org/news/13426468. I don't know if there are any spots open. I've never been to one of these. They have a lot of workshops going on over several day period. Different types of masonry heaters are built. They use clay so they can take them apart later. Looks festive with beer and pizza on hand. MHA sells an instruction manual. It is very basic.

And there is a masonry brick laying certification course, too. Usually, they have some masonry heater builders from Europe or Japan on hand doing their thing. Looks like a great place to learn. I built a masonry heater. I'm too far West so didn't attend Wildacres. Instead, I tagged along with some masons in Las Vegas to learn the craft. I did the dirty work - cleanup, mixing cement, hauling materials, etc.. but I observed and asked questions, too.

 

[qwee]

Building a Masonry Heater isn't that hard or complicated. Getting and carrying around all of the materials is the hardest part. It need not be expensive, either. I could build one for in the $1000 to $2000 range right now (not counting the pipe). So, let's build one in theory. First thing is to gather needed materials. There are two parts to a MH, the inner part called the core and the outer part. Let's start with the core.

We need fire brick, hardware, and a bonding agent. I would probably snoop around looking for used fire brick from a kiln teardown. I see $1/brick used fire brick 450 miles away from me.... But new brick is probably what most people want. Here are a couple of new brick sellers that I know masons use, https://www.wgpaver.com/ & https://www.alsey.com/. Hardware can be had at a reasonable cost from this company, https://www.firespeaking.com/. And there are other companies with more expensive but better hardware. Oops, the hardware should be with the outer part of the MH.

Now let's move onto the outer part of the masonry heater. If you are flexible here you can get this mass material fairly cheap. Say you want to go with conventional brick for your outer material. Brick masons always have left over bricks from their jobs (partial pallets). You could get 2 or 3 different brick colors at a discount (the masons will be happy to get rid of these taking up space bricks). The good thing is - you don't need that many bricks, so these partial pallets are made for your job. If not brick,

You could use natural stone or river rock for the outer part. Stucco or flagstone work good, too. I found someone selling 4" x 4" cubes of red and gray granite pavers - perfect for a MH outer part (not too thin or thick). Granite isn't as good as soapstone but it is good. They were cheap. The man-made jigsaw puzzle stone is becoming popular nowadays, but I don't like it, but some do. Nice thing is it fits together easily. I'm in Idaho - the rock capital state of the US (sorry Montana). Rock companies have discards that work good for a MH but are weeded out for wall sales due to some trivial reason like too short, off-color, etc.... Good luck.

 

[qwee]

Wildacres 2010 & general video,

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[DIYMasonryHeater25]

Have you ever done any masonry work before? What level of diy skill do you have? 2" is definitely not enough you will need to remove it and pour a proper foundation for this

I have done a lot of DIY projects, but this would be my first masonry project. (I've stripped multiple plaster rooms down to studs, insulated them, and put up drywall. I finished a walk up attic for a room , including the soffit vents, and designed and built a 'built in' bookshelf along one wall of my home office. The only things I want to avoid is electrical, plumbing and any gas lines.) I plan to see if anyone in my area is offering masonry classes, just in case it isn't as doable as I think it is. I would need to redo the basement floor just in the area the masonry heater would go. I don't want to redo the entire 1200 sf, considering the water heater, multiple tanks for the well, and the wall panel for the air to water heat pump system would be affected.

 

[DIYMasonryHeater25]

Wildacres 2010 & general video,

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Thanks...looks like something I would do, but will need to see if it is possible. The cost, knowing the basics and theory classes are already full, may not make sense. (I need the hands-on basics....without that, not sure if I would be better off finding someone teaching basics locally first. )

 

[begreen]

One of the basics is doing a soil compaction test first to make sure the big chunk of stone's foundation will not subside over time.

 

[DIYMasonryHeater25]

Building a Masonry Heater isn't that hard or complicated. Getting and carrying around all of the materials is the hardest part. It need not be expensive, either. I could build one for in the $1000 to $2000 range right now (not counting the pipe). So, let's build one in theory. First thing is to gather needed materials. There are two parts to a MH, the inner part called the core and the outer part. Let's start with the core.

We need fire brick, hardware, and a bonding agent. I would probably snoop around looking for used fire brick from a kiln teardown. I see $1/brick used fire brick 450 miles away from me.... But new brick is probably what most people want. Here are a couple of new brick sellers that I know masons use, https://www.wgpaver.com/ & https://www.alsey.com/. Hardware can be had at a reasonable cost from this company, https://www.firespeaking.com/. And there are other companies with more expensive but better hardware. Oops, the hardware should be with the outer part of the MH.

Now let's move onto the outer part of the masonry heater. If you are flexible here you can get this mass material fairly cheap. Say you want to go with conventional brick for your outer material. Brick masons always have left over bricks from their jobs (partial pallets). You could get 2 or 3 different brick colors at a discount (the masons will be happy to get rid of these taking up space bricks). The good thing is - you don't need that many bricks, so these partial pallets are made for your job. If not brick,

You could use natural stone or river rock for the outer part. Stucco or flagstone work good, too. I found someone selling 4" x 4" cubes of red and gray granite pavers - perfect for a MH outer part (not too thin or thick). Granite isn't as good as soapstone but it is good. They were cheap. The man-made jigsaw puzzle stone is becoming popular nowadays, but I don't like it, but some do. Nice thing is it fits together easily. I'm in Idaho - the rock capital state of the US. Rock companies have discards that work good for a MH but are weeded out for wall sales due to some trivial reason like too short, off-color, etc.... Good luck.

Thanks for taking the time to detail all of that out, and for the links. : ) Since it will probably be footed in the basement, I will likely use the brick outer wall as the exterior, instead of adding a different facing on the first floor. This weekend, I am taking measurements...of the basement floor to ceiling, the space between the joists that will limit the depth of the top of the masonry heater, and make sure there aren't any obstacles in the basement within the footprint of the space we have upstairs. ***what kind of clearance will i need from the chimney and the brick-faced wall in the living / dining room? Or from the joists/surrounding wood floor? That will definitely affect the design, and possibly affect the safety of it, as we currently have cats, and will have dogs after we retire. The existing chimney is against the wall in the dining room, and I planned to go from the chimney to the corner of that wall...it may only be 2.5-3 feet total.

 

[DIYMasonryHeater25]

One of the basics is doing a soil compaction test first to make sure the big chunk of stone's foundation will not subside over time.

I assume that can be done outside? I don't have to destroy the basement floor first, correct?

 

[bholler]

I have done a lot of DIY projects, but this would be my first masonry project. (I've stripped multiple plaster rooms down to studs, insulated them, and put up drywall. I finished a walk up attic for a room , including the soffit vents, and designed and built a 'built in' bookshelf along one wall of my home office. The only things I want to avoid is electrical, plumbing and any gas lines.) I plan to see if anyone in my area is offering masonry classes, just in case it isn't as doable as I think it is. I would need to redo the basement floor just in the area the masonry heater would go. I don't want to redo the entire 1200 sf, considering the water heater, multiple tanks for the well, and the wall panel for the air to water heat pump system would be affected.

Yeah just the area of the masonry heater. Masonry heaters are pretty involved and intricate constructions. Definitely would not be something I think a person should be learning masonry on

 

[DIYMasonryHeater25]

First off this is really light. Only 2x3 times heavier than a big stove.

Have you found plans? I would never attempt to engineer a fire inside my house on my own.

There are really nice stoves. A Blaze King almost as good as a masonry heater IMO.

My concern is that I am looking for a functional heater that isn't electrical. We are both in our mid 50s (this is our 'forever home'), and I would rather know that we need to load the masonry heater 1-2 times a day, and it would emanate the heat for hours. If we used the new(?) woodstove that is currently sitting in that space, my understanding is that it would constantly need to be fed, and would only heat a portion of the living/dining room.

 

[bholler]

My concern is that I am looking for a functional heater that isn't electrical. We are both in our mid 50s (this is our 'forever home'), and I would rather know that we need to load the masonry heater 1-2 times a day, and it would emanate the heat for hours. If we used the new(?) woodstove that is currently sitting in that space, my understanding is that it would constantly need to be fed, and would only heat a portion of the living/dining room.

Masonry heaters can work fantastic. But modern woodstoves can work as well. They can easily be loaded one two or three times a day depending on heat needs

 

[begreen]

My concern is that I am looking for a functional heater that isn't electrical. We are both in our mid 50s (this is our 'forever home'), and I would rather know that we need to load the masonry heater 1-2 times a day, and it would emanate the heat for hours. If we used the new(?) woodstove that is currently sitting in that space, my understanding is that it would constantly need to be fed, and would only heat a portion of the living/dining room.

A good castiron clad, freestanding wood stove can do this job and have more flexibility in operation with a much less complicated installation. Take a look at the Blaze King Ashford 30.2 as an alternative, or in non-cat, the Pacific Energy Alderlea T6 or the Jotul F55.

FWIW, friends have a Tulikivi soapstone stove in their forever home they built about 7 yrs ago. They like the Tulikivi, but said they wouldn't go with a masonry heater if they had to do it over. It can be a challenge in milder weather when daytime temps and sun warm up the house and an impact on livestyle when they want to go into the city for a show, meal, etc. and no one is there to stoke the beast.

Thread 'Tulikivi in action'

Feb 14, 2025

I got to see a friend's Tulikivi getting fired up today. It gets two daily firings @ 30# of wood per firing. Rather than loading the firebox full, they run a hot fire fed about every 30 minutes over a 2hr period. The stove is heating about a 2,000 sq ft portion of the house. Outdoors it was 38º and indoors a cozy 70º. The stone at the time of this feeding was around 105º. They also have a cook oven that they use throughout the winter when it's convenient.

• begreen
• Replies: 41
• Forum: All Other Wood Stove Brands

• 
• 

 

[qwee]

For clearances every area/county may be different. You will have to contact your specific code department. Where I'm at, the code department wanted at least 2 or 3 inches of clearance. I opted for 6" but made a mistake and ended up with about 4".

 

[EatenByLimestone]

Why don’t you think a masonry heater will act like a space heater? A house built to be heated by a masonry heater will often have it incorporated into multiple rooms so that its heat is put into those rooms directly. Heat is going to travel where it wants to travel. Some house layouts are better than others for this.

Theres also the issue of square footage, btu needs of the house, and the amount of energy available in the load of wood that you stuff into the burn chamber. If the thermal mass only releases 10,000 btu into your house an hour, and your house needs 40k, you’re going to be cold. 2400sq ft is a lot of space to heat, especially in an older home. If your btu needs are high, you may find yourself disappointed.

 

[stoveliker]

Just for comparison, I loaded my stove yesterday at a 9.30 pm.
This is a 2.9 cu ft firebox in the basement.
It was 26 outside then, the low was 17, and it just got above freezing here.

I will have to reload within the hour. So that's 16 hrs at least, heating a 825 sq ft basement and 1700 sq ft above that.

The point is that you can make a load last long if the stove has the technology to release BTUs at a low rate (a masonry stove can do that, and some wood stoves too), but this only makes sense if your home can remain comfortable with that low BTU input. Do that in an uninsulated shed and you'd still be chilly.

So, what BTU needs do you have? What is the fuel consumption of your conventional heating system?

 

[DIYMasonryHeater25]

Why don’t you think a masonry heater will act like a space heater? A house built to be heated by a masonry heater will often have it incorporated into multiple rooms so that its heat is put into those rooms directly. Heat is going to travel where it wants to travel. Some house layouts are better than others for this.

Theres also the issue of square footage, btu needs of the house, and the amount of energy available in the load of wood that you stuff into the burn chamber. If the thermal mass only releases 10,000 btu into your house an hour, and your house needs 40k, you’re going to be cold. 2400sq ft is a lot of space to heat, especially in an older home. If your btu needs are high, you may find yourself disappointed.

True. I am mainly concerned with the first floor, a bit less than 1000 sf....where the kitchen, laundry room and one full bath are, as well as the open living spaces. (We keep the doors for the rooms upstairs closed as well as the downstairs' sunroom and den, but I may keep the upstairs bathroom open if we have no power/no other source of heat to protect the plumbing there.)
We currently feel the cold air from the basement seeping up through the floor, so having the masonry heater in the basement and extending to the living/dining room would take care of 2 issues. And if I backpedal to a woodstove in the living/dining room, we need to have something in the basement as well. (We've talked of putting the other woodstove down there, and even getting a pellet stove, just to protect the water lines for plumbing and the heat pump.)

 

[qwee]

Two masonry heaters can be stacked on top of each other - so 2 fireboxes, one firebox in the basement and one on the main floor. It is only like 50% more work since they are on the same footing. But each MH needs its own chimney. Or if you just wanted a MH on the main floor, an 8 foot (or whatever the height) support structure could be made of masonry material (cynder blocks, rebar, & concrete probably). The ashes from the main floor could fall down to the basement support structure. Of course you would need to figure out how much under support you needed for all of this mass.

I guess you could do the reverse, too. That is put a masonry heater in the basement and a wood stove insert on the main floor. An insert with a good burn view for watching the fire. So many possibilities.

Heat-wise the insert above MH below would be interesting. The heat in the mass below would rise up (heat rises) into the mass on the main floor. So, you would have 2 sources of heat on the main floor - the mass and the insert. I've never seen that setup but it would work. It all depends on insulation and heat needs of each floor. You would have to figure out how to burn with this 2-headed burner. But for an old not well insulated house this might work well.

A MH on main floor and just a masonry mass in basement wouldn't heat the basement too well. Sometimes masons cheat and use common bricks below the firebox (they should be using fire brick) because they know heat doesn't travel down too much so they can get away with this cost saver (and no one will be the wiser!).

 

[DIYMasonryHeater25]

Just for comparison, I loaded my stove yesterday at a 9.30 pm.
This is a 2.9 cu ft firebox in the basement.
It was 26 outside then, the low was 17, and it just got above freezing here.

I will have to reload within the hour. So that's 16 hrs at least, heating a 825 sq ft basement and 1700 sq ft above that.

The point is that you can make a load last long if the stove has the technology to release BTUs at a low rate (a masonry stove can do that, and some wood stoves too), but this only makes sense if your home can remain comfortable with that low BTU input. Do that in an uninsulated shed and you'd still be chilly.

So, what BTU needs do you have? What is the fuel consumption of your conventional heating system?

I honestly don't know. We've insulated or built in a few rooms that have helped to keep those rooms warmer (like the kitchen and bathroom, which were made 'interior rooms' by enclosing the patio as a laundry room.) A few rooms didn't have radiators in them, like the sunroom, the bathrooms, and the new laundry room (and the upstairs studio, which is just storage right now.) So those will only have plug in electric heaters, since the quote to add another radiator to the laundry room was 4k! If I can DIY a masonry heater to add heat to the space (when we have the heat pumps working), it will allow us to not use electric heaters for some of those spaces. We've replaced all of the doors to the outside (3 of them) with energystar doors plus a similarly rated storm door. And the windows, which were replaced by the previous owner, still have gas in them. (There is only one room with the old windows...the sunroom. And we have no plans to do anything in there in the next few years, since there isn't any plumbing there.) And we replaced the roof. So the biggest loss of heat is literally the exterior uninsulated walls in the rooms we haven't stripped and insulated. I have no idea when we plan to strip the outer plaster walls in the living room, dining room, or our bedroom...or if we ever will. So, those are a known long-term issue.
I can easily deal with rooms being 60-65F in the winter...my husband, on the other hand, starts getting vocal when it drops below 72-75. Groan. We have a solar array (one of my lifelong plans), and we used up all of last year's solar credit by December/January. We just got the electric bill...it's over $1800 for the month. I plan to add more solar (we have the solar cells that were taken off the roof...just need to do all of that) and/or turn off/down electric heaters and other appliances. But that is a whole other issue. I just need to add more heat to the house when it gets really cold outside / replace the heat when we lose power, which has happened a few times already since we've been here. (It's been below 32F for the past few weeks, not just at night, but during the day, too.) Heaters will probably be running through March, into early April.
Sorry for all dumping all of that info, but the whole house has been a project for the last 2-3 years...after we moved here and the NJ house was sold.

Update: Our electric consumption ranged between 500 Kw and 1.2 Mw in April through June (includes some AC.) However, it was 5.4 Mw 12/17/24-1/18/25, and 6.1 Mw 1/18-2/18/25. Heating the old house (with little/no insulation in some walls) is beyond expensive.

 

[DIYMasonryHeater25]

Two masonry heaters can be stacked on top of each other - so 2 fireboxes, one firebox in the basement and one on the main floor. It is only like 50% more work since they are on the same footing. But each MH needs its own chimney. Or if you just wanted a MH on the main floor, an 8 foot (or whatever the height) support structure could be made of masonry material (cynder blocks, rebar, & concrete probably). The ashes from the main floor could fall down to the basement support structure. Of course you would need to figure out how much under support you needed for all of this mass.

I guess you could do the reverse, too. That is put a masonry heater in the basement and a wood stove insert on the main floor. An insert with a good burn view for watching the fire. So many possibilities.

Heat-wise the insert above MH below would be interesting. The heat in the mass below would rise up (heat rises) into the mass on the main floor. So, you would have 2 sources of heat on the main floor - the mass and the insert. I've never seen that setup but it would work. It all depends on insulation and heat needs of each floor. You would have to figure out how to burn with this 2-headed burner. But for an old not well insulated house this might work well.

Yes, I had that idea bouncing around in my head...but the 2 chimneys nixes two fireboxes. So, it's either support a DIY MH on the first floor from below, or DIY a 15-16' MH starting in the basement and extend the heated mass into the living areas above. (My husband basically said today that he doesn't want this (or any other interior projects) started until the other renovations are done....so there is a chance I won't start this until late summer....and I may not have enough time to DIY it before October/early November. (Maybe it could be finished in time for the worst part of the winter...December into January.)

 

[qwee]

Albie Barden is in Maine so not too far. Once you figure out what you might want to do you could run it by him and see what he thinks. He designed a MH for a member here who used it in a Yurt.
https://www.albiebarden.com/about

 

[DIYMasonryHeater25]

Albie Barden is in Maine so not too far. Once you figure out what you might want to do you could run it by him and see what he thinks. He designed a MH for a member here who used it in a Yurt.
https://www.albiebarden.com/about

I saw him in a panel on MH as a green option for heat in the past few weeks. I will reach out to him. Thanks.