Most Efficient In Home Heating

Zack,
Welcome to the forum.
My thoughts: the best thing you can do is minimize heating requirements. Its surprising how little heat it takes to warm a tight and well insulated house.
Consider incorporating passive solar. This is relatively easy and inexpensive to do when you're building new.
What you choose for heat as far a fuel whether cord wood, pellets, corn, gas, "electricity" etc. depends upon fuel availability and costs in your area as well as how much work you're willing to invest in heating.
Natural gas is cheap and getting cheaper most places. Its hard to beat for something that you "set and forget".
If you have ample nearby cord wood sources that's an option but it takes some physical investment of labor to heat that way.
Electricity is great and lends well to later PV conversion. There are some really efficient mini-split heat pump systems out there now.
You'll get some good advice as others chime in.
Good luck and have fun with the planning.

Edit; consider a single story open floor plan. This tends to lend itself to flexibility for heating. Also, high ceilings are pretty but its lower ceilings that keep the hot air where its needed.

Edit2: landscaping can impact energy efficiency. Evergreens to block winter winds and deciduous trees to the south can help with heating and cooling loads tremendously.

Edit3: with 2x6 construction you may need to add some foam panels on the exterior to get insulation values up.

If I were in your place, I would read up on the 'Pretty Good House' or PGH concept at GBA.
Start here...there are more: http://www.greenbuildingadvisor.com/blogs/dept/guest-blogs/pretty-good-house
Many guidelines from knowledgeable folks, re insulation levels, they rec this:

"Have 10-20-40-60 insulation. Hopefully these numbers are obvious: they represent a “pretty good” level of insulation in a cold climate for sub-slab, foundation walls, framed walls, and roof or ceiling, respectively."

You will not be able to get to this level with 2x6 conventional framing and spray foam (I assume you mean in the cavity). In conventional framing, 25% of the wall area is wood, at R-6, and the thermal bridging defeats all that expensive sprayfoam (which also might outgas nasties more than many would like). For less cash, you can go with densepack cellulose in the cavity and 4" of foam sheet outside, to avoid the thermal bridging. Detailing openings in the thicker wall is a small pain, but amounts to a bunch of plywood boxes anchored to the framing openings, and protruding through the foam. The siding gets hung off furring strips outside the foam, anchored to the framing by long (and slightly spendy) screws.

BTW, this insulation level is LESS than passive house, but it represents the current best tradeoff between energy costs and construction costs. Passive house is way more complex and expensive than this.

Aside form this PGH insulation level, you need to find a builder to build airtight, and willing to put a blowerdoor spec in the contract, (i.e. has done it before). Don't worry about fresh air....it will be supplied by an HRV, just as in millions of homes in Canada.

As for heat source....it will be small. In a Wisconsin climate, I would probably do either geo (if money were not an object) or a small propane-fired hot air furnace if it was (the usual case). The cost of the geo will pay your propane bills for many years to come. If you want AC, a small 1.5 to 2 ton central unit would be plenty. If not, a single window unit in an unused bedroom would prob keep the place cool and dry.

Of course, a small cat wood stove with an OAK would probably heat the whole place, and keep the propane man away.

IIRC solar in Wisconsin is not well incentivized. Site and orient the house to be 'PV-ready', with a large steep roof plane facing south, etc. Then have solar put in in 3-7 years when the cost makes it a no-brainer. Consider a metal roof on the south plane, or the whole roof.

What was the question again?

Slab on grade introduces some extra challenges. Plan on burying lots of foam. I was working on a project with an engineer that is building a passive house in Portland Maine on a slab. Slabs in Maine are rare but they are on ledge. Here is a link http://portlandpassiveproject.blogspot.com/.

They are going to a lot of work to get certified as a passive haus, a lot of the materials have to be shipped in as the local similar products don't have the right paperwork. That's why the Pretty Good House movement has sprung up, get 90% of the benefits of a passiv haus with far lower cost.

You should search on "Frost Protected Shallow Foundations". Basically a large skirt of buried sheet foam around the house perimeter, to keep the earth under the slab from freezing. What do you have against basements?

The Swedes routinely build insulated slab construction, in cold climates.
It is starting to catch on here as well.
I am intrigued by the integrated foam form poured concrete construction, they are getting common in my area.
Another approach I have seen is a double-wall 2"x4" framing, with the frame elements offset to break the thermal bridging.
Aside from ideas above, building smaller is a good way to go. Maybe shave off some sq. ft. and think about an unconditioned woodshed or garage loft for storage.

Double stud wall construction works too to get to high R-values....you can make a very deep wall cavity and fill it with the cheapest and greenest insulation—cellulose. Even if you build two 2x4 walls with the studs lined up (easy to build) if there is a few inch space between (for a 12" or thicker wall) then there is still no bridging, and it is easy to brace between the two walls. You still need to connect at top and bottom plates, usually falling back to 1/2" plywood which does have some thermal bridging. A more modern variation, is to use engineered wood I-joists in lieu of 2x12 studs. Again, easier for a builder to understand or mod existing plans...but the I-joists are expensive. Otherwise, you are still spending almost double on your framing lumber.

All the above seems to be rare in the US, expensive, understood by few builders, etc, and reserved for passive house projects. And depending on the air barrier methods, may still need foam on the exterior to keep the sheathing from rotting....so it is technically risky for durability.

The PGH approach IS conventional 2x6 framing, and the only thing weird is the window+door detailing, exterior foam wrap, air sealing details, and siding install....much simpler and cheaper to add than teaching the builder a whole new framing style and trying to find plans for it.

I am an open book as far as concept design goes and the house is looking to be 1750 sqft or slab on grade with 2x6 walls and closed cell spray foam insulation if this helps.

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Central WI puts you pretty close to the same temperature climate I have in central MN (47N latitude), at least as to seeing those -40'sF. Our house is 1500 sqft, single story, but with basement (you won't), pretty close to yours. If I had a do-over, these things (plus most of the other suggestions that complement) would be high on my list.

Heating/AC: not forced air, but hydronic in slab with a pellet boiler (and buffer tank) or a wood gasification boiler with substantial storage, plus mini-split heat pump(s) for summer AC as needed (probably minimal) and shoulder season heating, and also with a wood stove installed in a open, central area of the house.

Reasons: In slab hydronic is highly efficient, even heat. The wood stove would provide the supplemental heat over the slab temperature as needed, as slabs respond very slowly to warm up or cool down. Pellet or wood gasification boilers are substantially carbon neutral, wood more so than pellets (due to extra processing costs for pellets). Mini-splits use electricity very efficiently for cooling and shoulder season heating. Wood gasification with substantial storage (2000 gallons would be my recommendation) can provide hydronic heat between boiler firings, depending on temperature, from every second to third day to longer than a week. Pellet boilers can modulate output roughly between 30-100%, and a buffer tank increases their efficient operation. My bias is strongly anti-fossil fuel, thus no propane or even NG. Propane prices went out of sight last year. Wood and pellets both should be in plentiful supply in central WI with a pretty even market into the foreseeable future, and both are sustainable.

Site and build for passive solar: A southerly to SW facing houses with suitable windows and open floor plan can heat your house during the daytime on sunny days on just about the coldest days winter can offer, as it does for us right now. And with appropriate eaves your house will not be overheated during the summer. Extra building cost, if any, is minimal. A moderate landscape plan with some deciduous trees is OK on the south and SW, but not pines blocking the sun during the winter. Put pines on the north and NW to help block the cold winter winds.

Site for active solar PV: Large southerly roof exposure with pitch that maximizes solar potential for roof mount PV. Here there is a conflict with trees and shading. You need a large open expanse (site on a hill?) which provides essentially no shading from the south and as far to the east and west as you can manage. Where I live in MN the only incentives for PV were the federal 30% tax credit plus net metering at the retail rate. We installed ground mount solar last October (no suitable roof location due to shading), and I believe we now have eliminated our electric bills forever. A change in net metering can adversely affect that, but I believe technology on PV distributed systems, battery storage and other advances will make RE the game changer it quickly is becoming.

Consider adding active solar PV now: I understand the argument for waiting, but the fallacy is considering solar a cost (focus is on short terms economic payback) and not a value. And if you have net metering, the argument also fails on cost. Who buys a car for economic payback, furniture, or even a house? or who has children for an economic payback, or goes on vacation, or does a myriad of other things for economic payback? Life is lived for things we value, not for what they cost. Active solar has high value, IMO, and I also believe it pays back. Active solar just sits there and pays you for that privilege.

Some other ideas: 1) keep your roof lines simple, complexity adds building and future maintenance cost; 2) build as maintenance free as you can afford, not only future cost savings but also time savings; 3) build with good slopes and drainage, be careful about a high ground water table and runoff from neighbors; 4) the more square a structure, the more efficient it is and also, I believe, the more usable space it has; 5) open floor plans ease heating, cooling and comfort demands; 6) small special purpose rooms can be very wasteful of everything and not very usable, build spaces for multiple purposes; 7) highly efficient windows allow more glass and really open a house up to the outside, if that is important to you (our windows are R-8, U-0.12 and more energy efficient than some of our 1956 house walls, lots of glass, light, and perception of open space in every direction); 8) locate ideally close to work, school, shopping, etc., saves lots of time and expense related to driving, all of which translates to more time for everything else.

Living in a very old house I dont have as much experience with super efficient modern methods to offer as some of the very knowledgeable folks who posted above.

But I do have an idea for you... Why not combine these ideas /techniques along with some of the knowledge our forefathers had but got lost along the way in the era of cheap energy.

What do I mean?

#1 - Site for full southern exposure. Just having the house face the sun makes a surprising difference in winter even if you dont have dedicated passive solar elements.

#2 - Trees! Don't be like modern developments and cut them all down. Leave a lot of trees (deciduous) around the house - In summer they will provide valuable shade that reduces cooling load and then in winter they drop their leaves and let in important sun to give you solar heating.

#3 - Don't rule out multistory construction. The singe story open plan with 87 roof lines may be all the rage today, but the old New Englanders built boring two story boxes for a reason! Other than a dome, the box shape has the most efficient ratio of exterior surface area to usable floorspace of any building shape and has a big bonus of much lower roof area than a single story. This give s you a big advantage in lower heat loss in winter.

#4 - A variation of #3. Open concept is great for even heat distribution especially with a point source like a stove. But if you have central heat and want to save even more by only heating the space you are using, more rooms gives you the choice to close off spaces that are not being heated. This one is probably not such a big deal today but I point it out to illustrate there was a method to the colonials madness with lots of small rooms with low ceilings and narrow doors. The other variation on this is the late Victorian approach with a number of rooms connected by large double pocket doors that could be opened to make it all one big space or close off sections as desired.

#5 Ceiling height. As was mentioned cathedral ceilings are a nice design element, i too love the open feeling. But they suck if heating efficiency is your goal. OTOH for cooling high ceilings are a large benefit. Put together high ceilings, lots of windows with cross ventilation and high thermal mass masonry construction and you can achieve passive cooling in quite hot climates - something they knew back in the 1800s and the reason why Victorian age homes have high ceilings and tall windows.

#6 Windows. I always cringe when I drive through a McMansion development and see a house with a bunch of windows facing the road and then none on the side walls and few in back. You know these homes where all built with 24/365 mechanical climate control and artificial lighting in mind. Again there is a reason that all homes of the 1800s and earlier had a lot of windows and few or no rooms that did not have exterior walls (the only variation being that the hotter the climate the larger the windows where relative to the room). The obvious one is it decreases your need for electric or other means of lighting in daytime hours, but even more important:

• In winter - Having a lot of windows, especially if they are double hung and have good thermal blinds allows you to open all the southern window blinds up in daytime and let light in for solar gain, then close the blinds at night to hold that heat in.
• In summer - If you have a two story with a lot of double hung you open all the bottom sash on the first floor and open all the top sash on the second floor and let the stack effect drive a nice natural ventilation in the house. The colonials did this with the added benefit of functional exterior blinds (often mistakenly called shutters today) that where closed with the slats opened to block sunlight but let in air). You would be surprised how effective this can be without mechanical AC.

I dont live in any super insulated house.. in fact I live in a barely insulated house. But with full southern exposure and intelligent use of a lot of windows on sunny days in this joint we often dont need the heat until it dips into the 30s or low 40s. In the shoulder season when its in the high 60s in the daytime and dipping to the 40s at night I open the windows in the day and let solar gain get us up to 75ish, then close the windows and shades at dinner and can usually ride out the night without the house cooling that much. This time of year particularly I often have my windows open on days I'm reading that some members are already lighting their stoves.


If you put just a few of the above ideas together with these advanced building and heating technologies I think you can have an amazing house. Good luck!

OK, I"m gonna disagree with Jim (@jebatty) a bit.

IF you built it to PGH standards, that would be a specific heating index = 2 BTU/sqft.HDD. If you had 1800 sq ft and 8000 HDD in a season (for central wisc), that would be 2*1800*8000 = 29 MMBTU, about 400 gal of propane, OR 1.5 cords of wood, assuming no other heat source. In practice, a little passive solar, body and appliance heat would supply up to half of that, dropping you safely to <300 gal propane OR <1 cord of wood per season.

At these heating loads, the problem is getting a small enough furnace or wood stove to not overheat the place. That's why I would lean towards a small/cheap propane furnace, with ducts inside the envelope. At these low heating loads, the blower would easily distribute heat (unlike in conventional constructions) so 'comfort' does not require hydronics or extra thermal mass. Who would buy a wood boiler and storage to burn 1 cord per season? Rather, you would just need a small catalytic wood stove that you can throttle down, even in winter, or do one burn a day in the shoulder seasons, and use the furnace recirc to redistribute the heat (which works great in a PGH).

I am anti-fossil fuel. But for cost of a gasifier and storage, you could get a very small geo put in, and source its juice from a PV array. At COP=3 (conservative) it would require 29 MMBTU/3.414 MBTU = 8500/3 = 2800 kWh of electricity....only about a 2 or 2.5 kW PV panel to go 'net zero' for heating.

If budget was tight, you could build PV ready....buy your juice from a green utility for now, and then put in PV in a few years when it is even cheaper, and your bank acct has recovered. IF you have the cash now, roll it into the build and or mortgage loan.

I also think active solar space heating is a loser in the Midwest and Northeast US. These locations have a great annual resource (hours of sun per year) but a terrible winter resource (hours of sun in the winter) due to their weather patterns. With PV, it makes you the most juice and money spring, summer and fall. With active solar heating, it is DOA when you need the most heat. PV based approaches pay better in these locations.

woodgeek said:

That's why I would lean towards a small/cheap propane furnace, with ducts inside the envelope.

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I'm curious, why propane over electric heat pump? Concerns over using resistance heating when temps drop? Cost of propane heat is cheaper than electricity where OP lives?
Electric would allow easier eventual PV conversion with no need for a 2nd fuel (propane).

I'm assuming even the best minis will not hack it at Upper MIdWest winter temps, and so would only provide a shoulder season solution. Elec resistance would require 9000 kWh. IF minis covered 60% at COP=2 and the other 40% was resistance (a wild guess), that is still over 6000 kWh/year.

I also thought propane was 'cheap' in the midwest, when it wasn't spiking. And demand would be low enough that 1 tank would cover a season, so no buying in the winter.

It kills me to rec a fossil-fuel, but the OP would need to pencil out the numbers on geo/minisplit/propane to see what worked best, I can't rule out propane on its face.

woodgeek said:

OK, I"m gonna disagree with Jim (@jebatty) a bit.

IF you built it to PGH standards, that would be a specific heating index = 2 BTU/sqft.HDD. If you had 1800 sq ft and 8000 HDD in a season (for central wisc), that would be 2*1800*8000 = 29 MMBTU, about 400 gal of propane, OR 1.5 cords of wood, assuming no other heat source. In practice, a little passive solar, body and appliance heat would supply up to half of that, dropping you safely to <300 gal propane OR <1 cord of wood per season.

At these heating loads, the problem is getting a small enough furnace or wood stove to not overheat the place. That's why I would lean towards a small/cheap propane furnace, with ducts inside the envelope. At these low heating loads, the blower would easily distribute heat (unlike in conventional constructions) so 'comfort' does not require hydronics or extra thermal mass. Who would buy a wood boiler and storage to burn 1 cord per season? Rather, you would just need a small cat that you can throttle down, even in winter, or do one burn a day in the shoulder seasons, and use the furnace recirc to redistribute the heat (which works great in a PGH).

I am anti-fossil fuel. But for cost of a gasifier and storage, you could get a very small geo put in, and source its juice from a PV array. At COP=3 (conservative) it would require 29 MMBTU/3.414 MBTU = 8500/3 = 2800 kWh of electricity....only about a 2 or 2.5 kW PV panel to go 'net zero' for heating.

If budget was tight, you could build PV ready....buy your juice from a green utility for now, and then put in PV in a few years when it is even cheaper, and your bank acct has recovered. IF you have the cash now, roll it into the build and or mortgage loan.

I also think active solar space heating is a loser in the Midwest and Northeast US. These locations have a great annual resource (hours of sun per year) but a terrible winter resource (hours of sun in the winter) due to their weather patterns. With PV, it makes you the most juice and money spring, summer and fall. With active solar heating, it is DOA when you need the most heat. PV based approaches pay better in these locations.

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A wood boiler gives you hot domestic water, and propane is a fossil fuel.

brewerfan22 said:

Hey all,
I was very happy to find this website as I am in between heating options for my future home. My significant other and I are looking to build a home within the next two years and are trying to be as efficient as possible and use as little "on the grid" resources as possible. We are looking to build in Central Wisconsin and as I'm sure most of you know it can get pretty cold up here (last year we had solid -40 weather during the winter). So I figured before I put the pen to the paper designing rooms and features I would take suggestions from those experienced with the different heating methods and their efficiency to help me with this build. I am an open book as far as concept design goes and the house is looking to be 1750 sqft or slab on grade with 2x6 walls and closed cell spray foam insulation if this helps. Thanks for any input ahead of time!


Zack

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Look into straw bail construction, do as much solar as possible, consider a co-gen system using waste heat to heat your house and water. With a large enough co-gen electric vehicles pay dividends.

It may have been mentioned so forgive the repetition: for a tight house, plentiful fresh air year round and humidity removal during the heating season are very important. You need to plan for excellent HRV.

OWB for in slab heating?

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Makes me cringe.

A couple ponts of clarification....

'Active solar' usually means solar thermal panels, not solar electricity, which is photovoltaic or 'PV'. I think most of us are very positive on PV-grid tie, many members in here have PV systems, but you didn't say if you were open to it in your first post. @jebatty was recommending PV AND active solar thermal panels to heat water, which would be stored in a large tank as a 'heat battery' to allow you to store that solar heat and release it in a controlled way as needed. 'Passive solar' is of course just sunlight coming in windows, and dumping heat into the space.

Sounds like you are interested in self-sufficiency, and wood heat with 40 acres is def a great way to go. Insurers will usually require a non-wood heating system to be installed also, and that will be nice to have if you have to travel away from the house in winter. Since you won't be running it much, for the backup system you care more about low up front cost than you do about fuel cost. This brings you back to a cheap propane furnace with a tank of propane that gets refilled very rarely, or an electric baseboard system. The first one is easier to integrate with central AC.

For wood heat questions you came to the right place. Bottom line: a single wood stove is great for delivering a certain amount of heat, depending on the size 20,000 BTU/h to 40,000 BTU/h. If your house is poorly insulated (like many existing houses) then you need a lot of heat, and you need to go through many cords of wood a season. The result is not great...you are stacking, storing and hauling a LOT of wood, you need a huge stove or multiple stoves, and the far end of the house away from the stove can get cold....distributing all that heat is hard. Conversely, if you are well insulated, your wood consumption and work gets reduced a lot, you can buy a smaller stove, you can reload/burn less often, and distributing the heat gets a lot easier so temps are a lot more even, even with a single heat source in one room.

**From a self-sufficiency POV, I would build a 'super-insulated' house with above code insulation and airsealing levels, the most cost-effective route being the PGH, pretty good house. The resulting house would use far less heat than any house you have ever been in (probably only 1/4 to a 1/3 as much), so you would have to adjust your thinking re heating bills and fuel consumption downward. HRVs are still still expensive, the cheapest ones recover 50-60% of the heat from the air streams. Ones that do 80-90% are available from European sources, but cost many thousands of $. You will likely get one of the cheaper ones, which as I said, are standard in new houses in Canada.

**I still think you would get ducts inside the structure, and the smallest propane furnace and central AC unit they sell, and both would still be a bit too large. You would get most of your heat from a simple wood stove, a point source of heat, and it would mostly circulate naturally due to an 'open plan' layout. IF you wanted to boost the distribution, your furnace blower would help with that (get an ECM blower motor for efficiency).

**You would get your electricity from a PV grid tie arrangement, and would design the house with a good roof for solar...having one roof plane facing South or nearly so, and not making it too shallow of a pitch, and design out any penetrations (vents, chimneys, etc.) from that plane. The steeper pitch will get you more power and better natural snow shedding. Having the roof under your panels fail and leak is a real PITA, so, you might want to get a metal roof at least on that plane, rather than shingles, and the panels and roof could last together for decades.

Your plan is doable with current building science and technology, but many things that folks figured out decades ago will not apply. While you will get some passive solar heat, you will not be building huge south facing windows and huge amounts of thermal mass....that approach is very tricky and seldom resulted in a comfortable house. You will be super-insulated, and design a more normal looking amount of south-facing glass, with overhangs so the sun doesn't cook your house in the Summer.

This is obviously a wood-burning board, and this and the other rooms will tell you everything you want to know about wood heating. In a super-insulated house a lot of the challenges of wood heat will fall away, and you will just be left with the many pleasures of it.

But for building a house, you need to read up about that somewhere else....I rec Green Building Advisor. They have a huge amount of info and blogs about all the tradeoffs and options we have discussed above, and invented the PGH concept. You will be unlikely to find a builder who knows this stuff...you will find conventional builders who will talk you out of any 'more than code insulation' options, or will happily upinsulate some areas of the house he can do easily, e.g. the attic, but not others, resulting in bad thermal performance. IF you hunt around, you might find a passive house builder who can deliver you a 'passive house' that can be heated by your body heat, for an eye-popping construction cost. You need to find someone who is experienced building energy efficient super-insulated houses, but who isn't seeing you as a bottomless pit of money. You need to be knowledgable enough only to find the right person, so they don't sell you a bill of goods. And that will be the hard part.

My lack of clarity. I considered solar PV as active solar. I was not recommending solar PV to heat water and I was not recommending solar thermal to heat water. I was recommending a wood gasification boiler to heat water and with substantial storage to allow long periods between required firings.

My recommendation was solar PV for electricity in a grid-tie installation. Solar PV and mini-splits can work very well during much of a winter in the northern US. In my area of MN, only January typically is the really cold period. Much of winter is in the +10F and higher temperatures. The low point of solar PV occurs in January, and even then solar PV is 63% of maximum solar PV, which occurs in July. While winter days are short, solar intensity (low humidity, low atmospheric dust) combined with low temperatures results in very high solar potential. And even at current prices, if more electricity is needed in winter, it makes sense to add panels to provide needed winter electricity, which also may fit well for higher summer demand due to air conditioning.

I agree with everything Jim @jebatty is recommending solar-wise, and misunderstood his earlier post. He has great experience with PV not far from you. He also recommends 'minisplits' for heating....I like that approach for heating, but I had assumed would be a no-go in your climate. I'm happy to be wrong. You should look into them, they would provide cheap heat and AC.

I still think a wood boiler and storage is overkill for a super-insulated house.

... a wood boiler and storage is overkill for a super-insulated house.

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This may be true. My gasification boiler/storage recommendation was influenced by that use to heat my shop, 1500 sq feet, in-floor heat (constant 61F). During a typical winter I burn wood with btu content of about 56 million. That's equivalent to,16,500 kwh of electricity. At my general electric rate of $0.108/kwh, that is $1,780 annually for heat. That's also about 725 gallons of propane in an 85% efficient heating appliance, and use whatever per gallon cost might be reasonable ($2/gal = $1,450). I also have my own wood supply and c/s/s all of my own wood. At truckload rates for logs, purchase of this wood is about $250, or if purchased c/s and delivered, about $600 in my area.

Depending upon applicable rates in the OP's area, gasification boiler/storage may not be reasonable.

Mini-splits + good wood stove, heat pump water heater for DHW.

Next?

brewerfan22 said:

I have always loved the smell of a wood burner I am just not aware of exactly how well thermo-regulation would be from something like that? Also another consideration I would have is if I am burning wood within the home is there any potential for ash, carbon or the like to be in the air as a pollutant in such an air tight house?

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You might consider a masonry heater with a dedicated outside air source then. This combined with a backup system, especially something like a mini-split would seem to be ideal for your. You may even be able to incorporate some of the hydronic features you like into such a unit. though I've not seen it done. That might also be overkill.
If you like the idea of masonry heater now is the time to plan it in to your house. They are big honking stacks of rock that need to be centrally located.

OWB for in slab heating?
This was my second ideal option for home heating but not in slab. I was thinking more along the lines of running radiators in the homes and using the OWB like a traditional hydronic boiler. My only concern with this is maintenance and longevity. I will be on well water and it will be iron/sulfur rich and I am not sure what this would do to a closed loop system of heating. I know that the lines that are run are pex and would not rust but over time the water would become more and more like sludge or that's how it makes sense in my head. Would someone care to take a stab at this as well?

In slab pex if installed and used properly will use 1/3 less energy than radiators and is all around more comfortable.
In a better than average home (such as a pretty good house) a decent water heater could run your floor heat, and having excess thermal mass is critical to a passive solar design.

The ultimate therefore is a passive solar orientation and design, with in floor radiant tubes, solar hot water combined with a wood boiler with massive storage and for backup heat electric baseboard (it is cheapest and you should seldom if ever need it).

Oh, and I would set up your heat loops so you can drain and flush them every year and filter the inlet water.

Have you had a geothermal provider come out and quote? You probably could get by with close to the smallest system out there. With the tax credit it would cost about the same as a conventional system.