Some facts are at http://www.aaepassivesolar.com/index.htm
A superinsulated house with 2 layers of 2″ polyisocyanurate rigid foam on all six sides, carefully sited with most all its windows facing south, built atop a 70 to 100 ton mass of gravel, ‘crete, and foam with an embedded ductwork system inside, the small fan driving air down the central shaft into the heat sink, then out through the ducts and up back into the living spaces through floor grilles.
One is being built nearby.
Engineered materials and vacuum-press laminations prevent warping and keep a tall, flush-panel door from being excessively heavy.
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Replies
A good friend is building his house with that
heat sink system.
He is basing it on an old Hippy friend of his
house.
supposedly- 1500sf He lights a fire once a week
that heats water circulated throughout the heat sink.
If that works, he's doing very well for central New York!
I am skeptical of the viability of the package when built . . .
in this far north upstate NY latitude, . . .
at an altitude of 2000 feet, . . .
in a locale where the mountains hold in the cloud masses, . . .
and we typically get at least one week each winter where the high temp might reach plus 2.
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"A stripe is just as real as a dadgummed flower."
Gene Davis 1920-1985
Gene,
There is an architect inNova Scotia who has been designing and building houses in a similar fashion for over 20 years, His designs work here, but it doesn't get as cold here as in mid New York and, away from the coast, we do seem to get quite a bit of winter sunsine.
For a heat sink, he specs a slab on grade, 8" in thickness poured on 2" of polystyrene XPS with embedded 5" air tubes.
A few years ago, I built one designed by one of his fans, but it had a hill of a lotof surface area and far too many north facing windows and has been a lot of trouble for the owners. They have spent a lot of time and money refining systems that were not thought out very well and learning how to live with the house. It takes work and attention to live with a house like that.
Even before finishing that one, I started building my own house. Same ICF product, same usable square footage, but half the surface area, half the interior volume and relatively small windows. It costs very little to heat and is pretty much trouble free. Mine has a conventional oil-burning heating system. My telephone bill costs more than the heating does.
On another matter, did you know that Integra Spec now has a chamfered window and door buck insert block? I put some in last month. Easy installation, good and strong, but you end up wasting a lot of form material. They work on the sides of an opening. The top you still have to figure out yourself.
Ron
I have my doubts too.
He should be heating it this year, I'll report back.
Well lets see.
2000-2500 sf. ( can't exactly remember now)
In 1979 I built an earth bermed house based on exactly that concept.
North wall was 8" concrete, west wall was 10" cinder block poured full , eats and south wood frame.
Everything (including footings, stem walls) was thermally isolated from the ground with 2" of Dow blue. No west or north windows. All Glazing "state of the art" thermo pane for the day .Minimal east windows (kitchen area).
2x 6 walls, high dense Fiberglass insulation, Arkansas Framing so wiring and plumbing laid right on the sole plate for the walls, , 3-stud corners, single 2 x 12 headers without trimmers, (notched into the king studs). r-30 to r-50 roof/ceiling insulation.
20' by 12' solarium facing south with solar shade and active vents for summer that also was separated by 16' sliding glass wall from main building and was enclosed by the main building on the east and west sides.
High return air duct pulled warm air from the cathedral ceiling areas down and pumped it into a tunnel running the length of the house under the 6" slab.
Off the tunnel at 4' intervals were 4" dim ads pipes that came up into false walls and grills on the south and north walls of the house.
Toe kick electric heaters in master bath and kitchen sink area.
Main heat by the smallest high efficiency wood heater we could find.
Certainly not your climate , but the owners kept it to 70+ deg. all of the first winter on 1 1/2 cord of oak wood, including the first 2 months when they didn't live there so were adding no ancillary heat from cooking, body heat , lights etc.
IMO yes it should work.
Isn't this what Passive Annual Heat Storage is all about?
I will be the first to admit that VAToms houses are not as good looking from the outside, but the theory of building a concrete bunker with a south window wall and having the mass of the earth it is buried under keep it a constant year round temperature makes a lot of sense.
I would imagine someone could build some sort of hybrid that would look like a normal house but stay at a constant temp just because of construction.
Now if I can just get a giant solar water heater/storage system hooked to a stirling generator to power all of the lights and appliances and put that together with PAHS construction it could be off the grid and energy free with very little maintenance.
I know there are tons of bugs in a system like this, but I think it could work. What say you?
Here is some more detail. There are no footings, nor is there a concrete foundation. Instead, as is done when doing a precast foundation, a thick bed of gravel is carefully laid and tamped and leveled, after first doing a double perimeter drain using rigid PVC.
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Atop that bed goes a 2" concrete slab, then a membrane of the type used as a swimming pool liner is laid atop the slab. Then two inches of rigid foilfaced foam, joints alternated and all taped, then this arrangement shown here of ducting. The boxed mains distribute to the branches. Atop the center of the boxed main sits the downcomer tower that will run up the house center to the collection inlets up in the top of the house.
A fan setup inside the stack will draw air from the up top inlets and down the stack into the heat mass. This arrangement of ducts will be completely encased in a thick slab pour.
A woodframe foundation wall sits atop this slab, and that foundation will get the same two layers (4 inches) of foam wrap, then the membrane.
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"A stripe is just as real as a dadgummed flower."
Gene Davis 1920-1985
I am wondering how it will work also. Please report back and let us know, if you can.
Looks familiar!
House I did was (from sub-grade up) "moist-stop", 6 mil plastic, 2" Dow blue board, 12" 3/4" unscreened gravel with 4" ADS pipes embedded in it connecting to the same sort of main trunk line then 6" concrete.
Part of the concept in the house was that the slab would pick up solar gain when possible due to window orientation.
They can't get your Goat if you don't tell them where it is hidden.
"Atop that bed goes a 2" concrete slab, then a membrane of the type used as a swimming pool liner is laid atop the slab. Then two inches of rigid foilfaced foam, joints alternated and all taped, then this arrangement shown here of ducting."
Why is there insulation between the mass and the ducts? Would the heat or cool come out too fast without it?
This system is passive solar heating the way the Romans did it. As the designer/architect/developer explained it to me, the ducts in the 12" thick concrete storage mass slab are "concrete ducts with a galvanized lining, and the steel ducts are really just used for a form, a stay-in-place form."
Return air is taken from all the spaces in the house from as high up in the rooms as possible, and channeled in some way to the inlets near the top of the central return air shaft. Inside that shaft is a fan that is driving the air, quite slowly, down and through the plenum and finally out through those ducts in the mass.
From inside the mass, the "now-supply" air is distributed via the ducts to outlets near the floor, in the outside-perimeter walls of the rooms of the house. I am told that the airflow is very low, and not anything like that you experience in a house with a ducted forced-air system.
Here is the plenum being built. Look at the center of the central run, and you can gage where the shaft will sit over. All this ducting sits directly atop a "rat slab" of 2" of concrete, atop the two layers of foilfaced Thermax (foil up), that sit atop the waterproofing membrane, that sits atop the 12" bed of tamped crushed stone. #30 building felt was placed atop the tamped gravel bed as a "cushion" between the membrane and the gravel.
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The rectangular ducting of the central plenums will be top-sheeted in 3/4" PT plywood, really just to allow it to keep its shape and not deform when the concrete is placed on it.
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"A stripe is just as real as a dadgummed flower."
Gene Davis 1920-1985
Most systems will include the ability to draw outside air through the heat sink at night (exhausting outside), then circulate air through the heat sink and through the house during the day, to provide for cooling.
Too much sanity may be madness. And maddest of all, to see life as it is and not as it should be! --Miguel de Cervantes
Gene,
Is this right in Lake Placid area? I'm heading to Blue Mountain in a few weeks for the Rustic Show, might try and check it out. We did a passive solar earth bermed home back in the early eighties that used some of these concepts. Also had an area of angled Trombe walls for additional mass beyond floor and walls. No heat source other than a masonry heater in center of the house. It worked quite well, but was pretty expensive.
From the pictures and description it does seem like this would be pretty expensive construction unless an owner built project.
Mass is much too small for annual heat storage. Unlikely passive.
Gene's neighbor's design will work if the heat loss is balanced by gain. Minimizing loss, always important. Mass tempers termperature swings. Moving the heat is the innovation here.
PAHS can look like about anything you could image. My place, designed as a future furniture shop, is a bent box. Has more to do with getting it built (cheaply), using common commercial construction, than PAHS. Whose originator buried a dome.
Which Cloud was designing for a Kansas project. Total different appearance from my place, same function.
PAHS works. Bury it.
thank you, i was looking through old posts and came across a link with pictures of your place, very nice.
This concept has been around for 30 years at least. The FIL of my SIL had a house built this way, but it got flooded out and torn down, so I never found out how well it worked.
Anyway, after 30 years there should be enough examples spread around the country to give it a track record.
I think it might be a little longer than 30 years, didn't Thomas Jefferson's house use a system of underground air ducts to condition the living space?
The design that Gene is posting is an update that someone is currently building, and I am glad to see this subject being pursued.
It would be nice to see the other examples that have been around for years, and explore that track record. Do you have any hints where we might find some info on FIL,SIL,BIL, or DIL?
Yeah, the basic technique probably goes back to Roman times, at least. But the posted design (fans, gravel in the basement, etc) has been around virtually unchanged for at least 30 years, probably 40 -- I remember reading about it in Popular Science et al.FWIW, my SIL's (ex) FIL is Carlo DiCicco, a (retired) NDSU architecture prof. 701-280-9443.But I have to believe there's an online forum somewhere where the passive solar folks get together, and where you could find several folks with this setup.
Too much sanity may be madness. And maddest of all, to see life as it is and not as it should be! --Miguel de Cervantes
For all you folks hungry for data, go here http://www.cdhenergy.com/ and click on "Adirondack Alternative Energy," then use adirondack for user name and solar for password.
What you get is data from two test homes that were built per these specs and which have been set up with monitoring equipment.
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"A stripe is just as real as a dadgummed flower."
Gene Davis 1920-1985
I had a 75 minute one-on-one with the designer and one-man force behind this house design today, on site of the home in the photograph shown in the post above.
Here is a link to many more of the photographs of the project http://www.picasaweb.google.com/carolnevulis
Carol is the owner/builder, and is excited to be building her second one of these, having done one in about 1980 when she lived in Johnstown, NY. The same man was the source back then.
Here are some better facts, some of which correct some statements made by me in an earlier post.
The house must be sited with its "long wall" facing south
While I asked about whether there was a fixed ratio of glass area to cubic feet of inside volume, or square feet of inside space, I was told no.
But when I showed the designer a few examples of Sarah Susanka "Not So Big" house designs, he quickly said that they had too much glass on the "view" side. I guess there are limits. The house I am seeing built here has maybe 1/3 of its wall areas on the south elevation glazed, and it will have a couple skylights on the roof on that side.
In a nutshell, this design relies upon correct siting, a six-side exterior foam wrap on its outside, south-facing glass, and a massive heat storage sink in the ground under its main floor, with the embedded ducting and vertical intake "air return" shaft.
I was told that a cabinetmaker's precision must apply in doing the details of the exterior foam wrap. There are no discontinuities or voids allowed. Two 2" layers instead of one 4" layers, the product is Thermax, and foil faced, with a specified foil tape used on all joints.
Fee for the designer? $15K to $20K, which will include all drawings, specs, and periodic site inspections to ensure things are being done right.
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"A stripe is just as real as a dadgummed flower."
Gene Davis 1920-1985
Are you thinking of building one?
If I lived somewhere else where electric rates were "normal," I would consider it. Our rates are ridiculously low, in the 4-cents-per range, and our costs for heating run around $2,200 per year.
Heating costs don't go to zero with one of these houses. The one being built here will have two forms of supplemental heat, one being a wood stove, the other being electric. An electric water heater, oversized, will have a loop going to a coil in the air shaft.
If I was 35 and building my first house, and planned to live in it for a long time, the system would certainly make sense, provided my local energy costs were "normal." Even here, with our artificially low electric costs, it would make sense.
But at our age and house life-expectancy, it would just be crazy to undergo the cost of a build, a sale, and a move, just to save $2,200 per year. There is no payback for me, period. Just a cost.
Here is what you DON'T have to spend $ on when you build one of these: 1.) conventional insulation in wall cavities, roof, or attic, 2.) more windows than you need, 3.) a conventional heating system, 4.) concrete foundation walls.
Here is what you ADD to conventional costs when building one, versus "normal" construction: 1.) the designer's fat fee, 2.) the 4-inch Thermax foilfaced wrap on all six sides of the exterior, 3.) 8 inches more of concrete slab under the basement floor than normally, 4.) a whole lotta cost in caulking and sealing you wouldn't do otherwise, 5.) the cost of the air return shaft and fan and control, 6.) the cost of the ducting in the storage mass and the ducting to distribute to rooms above, 7.) the P.T. 2x4 sleepers and wood subfloor that goes atop the storage mass concrete "floor" under the basement, and 8.) the supplemental heating system.
Another cost element that can be big when doing one of these is that for the land. The south, east, and west sides of the house need to have 120 feet of clearance to any treelines, and that 120 can go up a lot if the south side goes uphill. All of this is to ensure that at the low angle of sun during winter heating months, there is sufficient exposure. What this means is that you will need a large building lot.
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"A stripe is just as real as a dadgummed flower."
Gene Davis 1920-1985
All good points in your summation. Well said.
They can't get your Goat if you don't tell them where it is hidden.