Thanks Boiler Room! My Tarm is up and running

Congratulations Thomas! Great Blog too!

Really nice blog. Best to you and yours. Off the grid too! Sweeeeettt!

Congrats! That is a nice blog and a beautiful home. You do nice work.

congratulations on getting yet another project finished in your home. The blog is really pretty amazing!!

Hi Thomas: I'm sure your happy you have your Tarm assembled and working. Mine has exceeded my expectations. Your house blog is my house blog of 25 years ago! alas no blogs in the 80's. You have written it for me. Not quite the same but I do love my warm timber frame home and my Stanley wood cook-stove. I stayed on the grid because of cheap power then and a large assortment of woodworking power machinery. My daughter and son-in-law are on my same road and off the grid completely. They are building their house as they go also. A Stanley wood cook-stove is going to be installed in their home too. As soon as more stone chimney veneer gets lay-ed up. Sweetheat

Congratulations Thomas. You know I have been following your blog for a few years now. Great work, as always. :coolsmile:

Hello Thomas,

I am SO happy for you. Very interesting....I just found this. I have some questions for you. It appears that you did not put insulation under the basement slab. Is this correct?
Is this because you insulated the walls of poured concrete?
Did this insulation of the walls make it unnecessary to insulate under the slab?
- I did a quick scan of your blog and did not find where you addressed this, if it is there just direct me to month/year for me to read.
I ask because we have a barn (in SW Wisconsin) which we will convert into our home. 36'x104' footprint. Hay mow is 25 feet from hay mow floor to barn roof peak.
First floor of the barn is the former milking parlor - 12" thick concrete walls up 8 feet, footings go down nearly 5 feet below level of the milking parlor floor.
We will use 3" of Sprayed Polyurethane Foam on the OUTside of the barn, from peak to ~4 feet below grade. Will this be sufficient to allow the entire structure to function as a huge heat sink (as it appears to me you have done) if I put in-floor radiant heat tubing into the newly poured concrete of the new First floor of the barn/home?
And then I will NOT need foam under the slab?

Sincerely,

Hankovitch in SW Wisconsin

Hello Thomas,

Thank you for your nice reply.
Some of what you mentioned I have seen....for instance, I have seen it mentioned that when you pour a slab one possibility is to insulate in from the walls several feet, and leave the remainder (center) of the slab area un-insulated. With the apparent wisdom of using the earth in the center as a huge heat sink. I imagine someone out there must have done the experiments to determine if it is wise(r) to insulate under the entire slab or leave the center uninsulated.
I imagine that if one can insulate the walls-and-outer-foundation with a few inches of water-impermeable insulation (your Blue Board), insulation going below frost line, then what you've done could be excellent.
Whereas if your walls-and-outer-foundation are uninsulated and therefore in communication with the sometimes frozen ground, then one could lose a lot of heat by conduction from heated slab to unheated concrete to frozen ground.
In this case of uninsulated outer foundation/wall it would likely be wise(st) to make sort of huge tray of water-impermeable (foam) insulation (foam over compacted gravel/sand, AND foam up the inside foundation wall to where the level of the floor will be --- now I need to draw a picture!)..... then add rebar over the foam, the add the in-floor radiant tubing, and pour the floor slab into this huge foam-insulated tray.
It will be very interesting to read what you find out a few weeks from now.
I sent links to this thread and your blog to my wonderful wife - I am certain she will find what you have done as interesting and educationally worthwhile as I have.
We will soon be having our in-floor radiant heat designed for us. I hope to be able to get well-reasoned answers to these questions from the people who will be doing the design. Apparently the people we have enlisted are quite knowledgeable. I will keep you informed as I get replies.

All 4 now,

Hankenstein in SW Wisconsin

Did you put blue foam under your footings?
Thanks

From what I've read, two big variables in deciding whether or not to insulate the slab are soil type and the water table level. If you have clay type soil and/or a high water table, the heat losses could go way up. Here's one thread I remember reading. In my opinion NRTRob knows his stuff. I ended up getting them to design our radiant system.

http://www.greenbuildingtalk.com/Forums/tabid/53/forumid/12/postid/23503/view/topic/Default.aspx

"Whether you need slab insulation or not depends. You most definitely need insulation on the vertical outside edges of your slab. That is a significant source of heat loss. You also need to insulate the outer 5' perimeter of the slab, where it is still seeing higher loads from the surrounding ground surface.

As for the center of the slab, if your ground is clay, rock, or wet, you definitely want to insulate fully. Those conditions can make for a heck of a heat sink. I saw a slab up here in maine (built on ledge, which is everywhere up here) that literally could not maintain temperature in the spring when the ground was wet. wicked all that heat right out.

If you have good natural drainage, no standing water, no high water table, and good loose or sandy soil, then you could get away with less or no insulation in the center of the slab. If you're in doubt though, you should insulate. That's not an easy mistake to fix later. You can replace windows.

Even in that case though, you do lose heat to the ground unless you are maintaining ground temperature or lower for a slab temp. Perhaps not enough to pay for the added insulation quickly.. but something, yes.

We generally go with a reduced center insulation or none only on very large slabs (where it's mostly center area), or in mild areas with the above noted soil conditions. In a normal residential slab, I don't think it's worth trying to "play the dice" there unless you are very sure of your soil conditions year-round and your water table. And even then, you're not going to save that much since the perimeter and edges still need to insulated, no matter who or where you are.
"

Hello Thomas, Oldmilwaukee and Jackpine Savage,

Thank to all of you for your inputs, and for the link to another thread on insulating a slab.
Very worthwhile information in what you've written.
Our farm is in a wide, low, level valley. There is a small river running through our property, and on part of the property this river forms part of our property line. I recently used the Bobcat 'pallet fork attachment' with only one fork on it, and dug down at a random location adjacent to the foundation. The clay soil was wet all the way down. Looks as if the wisest thing to do will be to make that insulated tray, add rebar, add radiant tubing, and pour concrete. I WILL first remove the existing floor - once I've done that I will level things off with a Compacter, and put down a layer of 2" thick blue board. I will likely have them apply ~1 inch of SPF over the Blue Board and up the concrete at footings and up the concrete at the perimeter to make that 'tray' mentioned in an above email. Then add the rebar, tubing, concrete.
I believe I will go with your idea Thomas, and err on the side of structural caution - and not insulate under the footings for the newly located posts which will be placed every 8 feet or so down the 104 foot length of the barn, and will be holding up the 5 sistered 2x12s, making the 'beam' which runs the full 104 foot length of the barn, and holds up the Hay Mow (the future living space of the barn/home). I believe this should give me good strength and sacrifice only marginal heat loss. And, since it is an existing structure I will just have the backhoe operator dig down about 4 feet (footings for the 12" thick concrete barn wall go down at least 4.5 feet below barn's 'ground level' floor), clean off the concrete, and apply 3" of SPF, then back-fill. I won't have the awesome 7 feet below grade insulation you have Thomas (how GRAND), but at 4 feet is IS right at the agreed-upon frost line for where we live in Wisconsin.
Thomas, I see you mention you have 4,000 feet of Radiant Pex...we will have something similar. Did you put radiant floor heat in all levels of the home?
I am thinking of having the Pex in all levels - what do you think?
What did you do?
And why?
First floor (former milking parlor) will have 3 zones - ~20 to 25% at each 'end', and 50-60% in the middle.
One end will be garage bays, other end will be horse tack and horse grooming area (no stall), middle will be workshop and access to the attached structure where we will house the GARN WHS2000.
Second floor - main entry, kitchen, dining, great room....all open, bath, study, game, office.
Third floor - loft; bedroom 1, bath 2, bedroom 2, master bedroom with bath 3.
I am unsure how to do the zoning on 2nd and 3rd floors....but our radiant heat design guy will educate us. He has been doing this for systems using a GARN for 20+ years, and has (in his words) people 'bordering on brilliant' when it comes to designing radiant floor heat systems with the GARN..... as backup for when he is stumped.

Sincerely,

Hankovitch in SW Wisconsin

If you are going down to the joists and installing subfloor for your remodel, one product to look at is Warmboard . I think it stands head and shoulders over the other alternatives, but it isn't cheap. I ended up going with aluminum extrusion plates under our existing subfloor.

Hello again all…....
I am posting this in a second thread, please accept my apology if you are reading it twice.
I hope you will see its value.
Hankovitch here to report on what we’ve done so far on our Barn-to-Home conversion project. We decided to “go” with the 3” of Close Cell Polyurethane Foam on the outside of our barn….from 3’ below grade (wanted to go 4', but couldn't) all the way up to the peak of the barn, and back down the other side once again to 3’ below grade. A monolithic application of 3” thick foam on the barn, outside, covered with a polyurea paint as final coat to protect from UV light and the weather. Essentially as they re-did the Superdome roof after Katrina destroyed the EPDM roofing. We are doing this in stages, and I report here the current state of the project and what I will call the results.
We have dug out around the foundation of the 36’ x 104’ barn, 4 feet down…..pressure-washed the dirt from the foundation/footing……then applied 3” of SPF to the foundation (down 3’ below grade), and applied 3” of SPF up the 8’ high, 12” thick concrete wall of the milking parlor and up another foot……then sprayed a polyurea paint over the foam…..drain tile was put in around the foundation and runs to one of our ditches 300 feet from the barn……then we back-filled where they dug out around the foundation………then we also applied 2” of SPF inside the barn, to the milking parlor ceiling (underside of hay mow floor)………..we put 14 new windows, 3 new doors, and a new 7’x9’ garage door in each end..………
In this 3,500 sq foot area (the former milking parlor) the only source of heat is passively from mother earth…down 4 feet the temp of the earth is approximately 50 degrees F…..
Bottom line on how well the insulation is working.
Since Jan 1, 2010 outside temp has ranged from +39 F to -14 F.
During that same time period the inside temp of the former milking parlor has ranged from +33 F to +37F.
The important thing to note is that, even though the outside temp dropped to 14 below zero, the inside temp always stayed above freezing….on some days inside the milking parlor has been as much as 47 degrees warmer than outside!
Note, this is with PASSIVE geothermal heating…..we do not have a heat pump, there is NO source of ‘heat’ for the barn other than what mother earth supplies by heat passively (and continually) coming up through the concrete slab of the milking parlor floor!
Furthermore, there is no ‘earth berm’ of the barn, the entire milking parlor is above ground.
Pretty awesome, I’d say…..

And, it will only get better as we…
- put on storm doors (for the three doors we put in),
- complete the back-filling (in some places the back-fill is over a foot low), and
- close off the openings of the two stairways (at ceiling of the milking parlor) with something better-insulating than the 3/4 OSB we now have covering the openings.

By the way, I’d love to hear how things went for the fellow who started this thread. What do you have to report, now about a year since the thread started?!

Sincerely,

Hankovitch in SW Wisconsin.

Hello Tom,
Interesting real-world experience you describe with unseasoned (not dry, aka 'wet') wood.
First, I am wondering...is the Tarm you are using is a gassifier? If yes, you should be burning the creosote in the secondary burn chamber, and you should not have what you describe as the soot (creosote?) buildup in your chimney nearly plugging it. If that is the case it argues VERY strongly about not burning wet wood....as I imagine there may have been sufficient water vapor with the creosote to preclude efficient burning in the secondary chamber, much of the creosote made it to the chimney where it condensed on the inside, dried out, and caused the 90% wood burner creosotic plaque. I'd call Tarm and ask them.
Now something additional on burning wet wood.
I posted this about a year ago on another thread, thought it would fit well here...
When purchasing wood for burning you needn’t ask if it is dry (the seller will always tell you it is dry!). Just look at the ends of the wood pieces where the chain saw cut through the tree. If you see what appear to be a number of slits, cracks or gaps where the wood fibers have separated, then it is at least somewhat dry. If the wood appears to be tight (no slits, gaps or cracks), then the wood is NOT dry, and you will use a lot of energy just to drive off the water before you can burn the ‘wood’.
Late this Spring or early Summer cut some wood of your own, split it, weigh it immediately, and record the weight on the ends of several pieces. Dry it for a while - 1 week, 3 weeks, 2 months, 4 months - and record the weight of the pieces through the Summer. It will be an interesting and revealing experiment. Let's look at a cord of wood (4'x4'x8'= 1 cord).
Let us assume the cord of wood you purchased is wet enough that it still has 400 pounds of water in it. (probably a VERY conservative number for an entire cord of freshly cut wood….freshly cut wood can be up to 80% water, and ‘seasoned’ or ‘dry’ wood will typically still contain 15-20% water).
See the link http://www.i4at.org/surv/woodburn.htm
(Note: this link has information confirming that burning wet wood can be a cause of creosote buildup in chimneys)
Thought I’d try a fun calculation here to determine how much energy you will use just to drive off the water, and thereafter allow the wood to burn..
To heat water requires 1 BTU per degree per pound of water. Thus to heat one pound of water in the wood from 32 degrees F to 212 degrees F (to the temperature where the water can begin to boil away) will require 180 BTU per pound of water.
This means that you will use 72,000 BTU for the 400 pounds of water in the wood just to get the water to 212 degrees F.
But the water is still there, as a liquid - it is just a liquid at 212 degrees F!..........so read on.........
To convert 1 pound of liquid water at 212 degrees F to one pound of steam at 212 degrees F (where it will then have all 'boiled away') will require 970.4 BTU per pound of water….really.
For the 400 pounds of water, you will need to use 388,000 BTU to complete driving off the water.
Or, starting at 32 degrees F, for a cord of wood which still has 400 pounds of water in it, you will utilize 72,000 BTU + 388,000 BTU = 460,000 BTU jsut to drive off the water.....now you can use the BTUs in the wood to heat your home. This is 460,000 BTU which is NOT available to heat your home!............this is why it is best to dry the wood.

Also, you can purchase a unit to test the moisture content of the wood you purchase, (or the wood you cut and are drying) if you want to get high-tech.
See the below link…...and there are many other sources.
http://www.drillspot.com/products/437287/Extech_MO210_Digital_Moisture_Meter

Personally, I purchase scrap pallet wood. It runs about $12.00 per cord. Yes, it has nails in it, but I now just shovel them out from my OWB....and get paid by the ton to recycle them in the Spring at a local metal recycling facility. In my Garn (to be up and running for the 2010/2011 heating season in our Barn/Home) I will simply remove the nails with a magnet on a pole. One reason for burning pallet wood --- it is kiln-dried, and as such has a moisture content around 6-10%!! With the kiln-dried wood I waste very little of the BTUs in the wood to 'drive off water'.

Sincerely,

Hankovitch in SW Wisconsin