PDA

View Full Version : I have a design idea/question (house)



Phillip Allen
02-11-2007, 08:57 AM
It is about heating. Thinking about the heated floors, what about using masonry walls as well (think of masonry mass)?

Paul Pless
02-11-2007, 09:10 AM
I'd be concerned that unless the exterior of the masonry walls were insulated on the outside you'd be expended some of the heat energy outside of the living space. Plus, part of the efficiency of heated floors is that heat rises.

note: I'm not an architect, i just play one on the WBF.

Phillip Allen
02-11-2007, 09:26 AM
Yes...all exterior walls must be well insulated. This house is ALL masonry in as far as its walls are concerned. All partitions are structural tile and plaster. The outside walls are the same tile with brick outside of that (about 10 inch walls). Even with the air temp up after I raise the thermostat in the mornings, it takes a while to re-heat the walls to stop the chilling effect of the (relatively) cold masonry.

rbgarr
02-11-2007, 09:45 AM
Are you aware of masonry stoves or 'Russian' fireplaces?

http://www.hollowtop.com/cls_html/do-it-yourself/masonry_stoves.htm

Phillip Allen
02-11-2007, 09:51 AM
Are you aware of masonry stoves or 'Russian' fireplaces?

http://www.hollowtop.com/cls_html/do-it-yourself/masonry_stoves.htm


Only "just". I've been a commercial mason my whole life and these things are residential in their nature. Still, the idea comes naturally. I was thinking of a way to heat heavy masonry interior walls effecently.

StevenBauer
02-11-2007, 09:52 AM
I'm in the final stages of building just such a house for a client. We used Durisol Block to build the walls. These blocks look like concrete block but are made from recycled wood and portland cement. They have some rock wool insulation in them, also. After they are stacked up and rebar inserted and electrical wiring placed inside (in conduit) you pump them full of concrete. The cross web of the block is cut out at the top and bottom so there are steel reinforced concrete beams all through the wall hoizontally and vertically.
Like this:

http://www.durisol.com/graphics/wf%20photo%20023.jpg

These walls are rated for R 20 but with their thermal mass they will perform like an R 40 wall. The roof system has 24" of dense-pack blown in cellulose insulation for R 80.

Here is a video I took back in October before the concrete was pumped in to the first floor walls.

www.youtube.com/watch?v=GxYcUhTiJM4

Our "plumber" screwed up the heating system last week by making some changes to the system. So the house had no heat on from Friday night until we got there Wednesday morning. (Monday and Tuesday I worked at a different job) Temperatures over the 5 day period were in the single digits (f) in the day and down to minus 10 f) at night. I know a conventionally framed house would have frozen up solid, with all the pipes burst, etc., but when we got there Wednesday morning the inside temp was still 37 degrees. And our "plumber" was off snowmobiling in Canada for the week! (I got the heat going with the help of the furnace manufacturer).
I've got lots more pics, maybe I'll take some more movies next week.

Steven

Phillip Allen
02-11-2007, 09:57 AM
vapor barrier?

StevenBauer
02-11-2007, 10:05 AM
vapor barrier?

Good question Phillip. :) The sections of the house that are wood framed, the gable ends (double 2 x 4 walls 12" thick), the roof (trusses 24" thick) and the bay window area (2 x 6 walls with 2" of styrofoam on the inside) have a very well sealed 10 mil vapor barrior. The sections of the house that are Durisol Block have no vapor barrior as they actually "breath" They let water vapor migrate through the wall helping to keep the air inside healtier.
The main heat system is a small wall mounted unit that heats water circulating through the slab through hepex tubing.

Steven

Phillip Allen
02-11-2007, 10:08 AM
Doesn't the "breathing" wall insulating abilities degrade with the progress of a cold wet winter as the outside freezes up and loads up with moisture?

StevenBauer
02-11-2007, 10:16 AM
I think the moisture comes through so slowly that it isn't a problem. It's also very dry here in the winter.
On the outside of the house we wrapped Typar then nailed on verticle strapping and we will have pine log siding over that. So from the outside it will look like a log cabin. Inside we nailed on horizontal strapping then nailed on v-match t&g pine.

Steven

Phillip Allen
02-11-2007, 10:19 AM
How would you modify it for a winter with alternating wet, snow, wet, never dry but often below freezing and violent spring weather (tornados)? Heavy tree cover (hardwood).

Phillip Allen
02-11-2007, 10:22 AM
also, how would one go about attaching wall ties to the blocks (for brick)? On regular lightweight blocks, I prefer a stud gun with 3/4 or 1 inch nails driven into the webs of the blocks and not the joints. (On commercial work, the practice is to use hook and eye (pentil and gudgeon) wire in the block)

StevenBauer
02-11-2007, 10:25 AM
No modification neccesary. Once you pump these walls full of concrete they are stronger than the proverbial brick S***house. Metal roof, roof overhangs all around. We were in the house the other day with 40 -50 mph gusts whipping up the field, 12' long 1 x 6 boards left outside were blowing off into the woods but inside the house you'd never know it was windy if you didn't look out the window.

I'm off to help my dad move for the rest of the day but I'll check in here tonight and answer any questions you can think of and I'll post some pictures, too.

Steven

StevenBauer
02-11-2007, 10:27 AM
also, how would one go about attaching wall ties to the blocks (for brick)? On regular lightweight blocks, I prefer a stud gun with 3/4 or 1 inch nails driven into the webs of the blocks and not the joints. (On commercial work, the practice is to use hook and eye (pentil and gudgeon) wire in the block)

These blocks are like 90% wood. You can just nail or screw into them with deck screws or galvanized ring shank gun nails.

Steven

Phillip Allen
02-11-2007, 10:30 AM
I see...sounds good. Can you get a brochure from the manufacturer for me? (or maybe a website)

Phillip Allen
02-11-2007, 10:31 AM
BTW...if so much wood is involved, what about termite coverage? Insurance rates for fire protection?

Phillip Allen
02-11-2007, 10:33 AM
Oh yeah...load bearing abilities? (bond beams all around?)

Mrleft8
02-11-2007, 10:54 AM
Trom (b?) walls I think they are called. A thermal mass within the structure. Quite often a thick masonary floor on the southern exposure, with a lot of glass.... But also can be made of simple things like water filled barrels painted black and set in a sunny location.

merlinron
02-11-2007, 12:04 PM
not really sure what they are called, but there is a system similar to the durisol sytem that is made of styrofome. i'm sure you guys have seen them, they're sold at HD now. they have wood backing for interior and exterior finish cast into them. assembled like big building blocks and them concrete is poured in thier core.

Paul Girouard
02-11-2007, 12:21 PM
There's a few outfit's making foam block forms , that look to be like Steve's project.




http://www.toolbase.org/TechInventory/techDetails.aspx?ContentDetailID=602


http://www.pathnet.org/sp.asp?id=14138&f=2


I have yet to use any , here in the PNW most homes are on concrete foundations , some slab on grade , most with crawl spaces (which tend to be unheated spaces , in fact vented to outside air type spaces , so insulation is not needed. A few on sloped site have full on multi stepped basements / some daylight basement, few are the full basements folks in the mid west and east coast are used to.

The only down side I've heard , other than cost which if you decide that they are "for you" / you want to use them , is when it's warm / hot out (rare here in PNW) the forms get a little wimpy / wavy-ie / more bracing than normal needs to be used , sort of sooner, like as you assemble , to keep everything straight. Once a twist / bend gets introduced and the form cools down at night that twist / bend / bow is hard / impossible to get out.

Other than those down sides it all seems to be good news !

paladin
02-11-2007, 12:47 PM
If you have concrete poured floors, and consider running some form of heat system through them, you might give it some second thought.
In Iceland they do not heat their water....they pump superheated steam from beneath the glacier (volcano down there) and pump the superhot water into large storage tanks. (the Germans bombed them during WWII thinking they were fuel).....that hot water in turn is pumped through below ground piping under all the roads from Keflavik to Reykjavik to Akreness.....never any ice or snow on the roads....
They also pump hot water to all the homes. It's mixed with ice cold water for drinking and general household use....it's also pumped through the heating system on cold days and through the floor of Icelandic homes. Icelandic homes are normally built of cinder block with cement slab floors and tile over.
There is a small scale problem showing itself after almost a generation of this. It seems that the heated floors, in combination with the hard concrete is taking it's toll on the legs and joints of Icelanders.....and they have determined that much of the problem lies with the heated floors...

Paul Girouard
02-11-2007, 01:02 PM
Sort of a low tec "ingenuis idea "using natural steam , turns to water as it cools down and gets to point of use:cool:

I wonder if it's more the concrete floor not so much the heated part :confused:

People do come up with some cool ideas :cool: That use of steam is almost to simple in a way.

Sort of like insurgents using common garage door openers to set off IED's simple , but effective. Well it was till the Prowler's and com. caught on to it.

StevenBauer
02-11-2007, 03:39 PM
Phillip, the site is: www.durisolbuild.com (http://www.durisolbuild.com)

You asked about load bearing. After you pour concrete into the stacked up blocks you end up with steel reinforced columns and beams. The horizontal beams are about 4" x 6" one foot on center. The verticle columns are about 6" square on one foot centers. These intersect every foot and the rebar is tied together. These walls are amazingly strong. They build 10 storey apartment buildings out of these blocks. They are really just insulated forms.
And the wood is mineralized, bugs wont eat it and they are fireproof, too.

From the FAQ's:

"This means the wood is chipped to specific gradation, the fine particles are removed, and the wood is mineralized. Mineralization is the proprietary process by which we remove the sugars from the wood and render the material completely inert, and no longer susceptible to rot or termite damage. The wood then becomes an inorganic aggregate similar to stone aggregate in concrete. Durisol is also known as “wood-concrete”. It is the mineralization process that allows the cement to hydrate or “strengthen” in the presence of wood particles.

The mineralization process is an interim process only and all Durisol products, once made, are comprised of cement and wood fiber only. There are no residual chemical properties whatsoever from the wood processing."

Ron, the generic term is ICF: insulated concrete forms. My client chose Durisol since it's made up of recycled wood and cement, not petroleum byproducts. And the fire scenerio. Do you know what happens when styrofoam burns? Yikes!

Steven

Phillip Allen
02-11-2007, 03:59 PM
(Do you know what happens when styrofoam burns? Yikes!"

Ask any fireman's widow

merlinron
02-11-2007, 05:56 PM
hey steven.. yup that's the name. i should have known it, but the recall is getting weak these days.....i believe the flamability problem is addressed with a retardent when they make the polystyrene. IIRC, polystyrene is the least toxic of the commercial foam insulations also.
the cost is a consideration, but it is something like 30% moer expensive than conventional poured walls, so it is off set by no need to insulate the wall. there are a few houses up here that have been built with it and the owners are satisfied. this area is awfully oldschool yet and new ideas don't catch-on easily. my own house, a raised ranch, i built a wood foundation.... people thought i was nuts, even my friends.... now ten years later they are amazed how comfy my lower level is and how there is never any damp feeling or smell....

StevenBauer
02-11-2007, 08:42 PM
Cool site Few. Type Durisol into their search engine and you get some links to some projects very similar to mine.

Steven

Phillip Allen
02-11-2007, 08:54 PM
ya know...we got away from my original thought...which was how best to heat walls

StevenBauer
02-11-2007, 11:04 PM
Do you want to heat interior walls? Or heat the interior surface of the exterior walls? Thermal mass is important. But most important is a high efficiency building envelope.

Steven

Phillip Allen
02-12-2007, 03:41 AM
don't know...just kicking around the idea of heating the vertical surfaces (beyond any other heating)

ishmael
02-12-2007, 07:22 AM
I've never worked much with masonry, or built a super-tight house. I'd like to try my hand at masonry work. Done a little tiling, and too much plastering.

With really tight houses what about the concern over indoor pollution, particularly if you heat with wood? I've never lived in one, but when I've been in them I felt a little claustrophobic.

I'll be curious to see how this discussion develops. I've been considering replacing this place with a small solar cabin. Maybe 800 square foot, frame. I've got a perfect exposure, and this loose place basically heats itself on even the coldest sunny winter day. With a proper design I think you'd be looking at a chord of wood for a winter.

Phillip Allen
02-12-2007, 03:11 PM
I have thought about the effect of adobie (I've actually layed the stuff) but It wouldn't work here of course. but what about two masonry walls with a large space between...they would need to be tied together but then pouring sand with a little portland in it so it wont move later and give it a huge thickness...

paladin
02-12-2007, 06:42 PM
My house in Chaing Mai, Thailand was up in the mountains, and it got really cool up there, especially at night.....the house was built of two layers of cinder block with air space between them, then they filled the space with glass bottles which they melted the end shut, then poured loose sand between them. In the middle of the living room floor was the equivalent of a stone hibachi for heat or cooking, with a vent at the top......about a half dozen times during the "winter" did we make a fire at night....and it may be coincidence...but it seemed like the days when I would come home from 2-3 week work run...cause...I usually brought home marshmellos.....

merlinron
02-12-2007, 06:53 PM
i can recall reading some articles about hydronic heat in the walls being fairly common in europe....italy specificly. this was about 25 yrs. ago when i was researching the cost/meathods of hydronic heat for my first house.

with the form system

Figment
02-12-2007, 07:19 PM
Oh yeah...load bearing abilities? (bond beams all around?)

THANK YOU!!! The last three times I've said "bond beam" to a mason I've gotten blank stares. I was beginning to think they had become some kind of antiquated specialty like portland terrazzo or something.

Phillip Allen
02-12-2007, 08:59 PM
THANK YOU!!! The last three times I've said "bond beam" to a mason I've gotten blank stares. I was beginning to think they had become some kind of antiquated specialty like portland terrazzo or something.


Maybe it is the difference between commercial and house bilders

oldsub86
02-12-2007, 11:26 PM
I have just been reading some books on passive solar heating and super insulated houses. The one on passive solar provides an example of a home with an interior masonry wall and an exterior wall of glass about 2 feet apart. There needs to be enough room between them for a person to go in and clean the glass periodically and remove the spider webs etc. Essentially the sunlight coming through the glass heats the masonry wall during the day and then the wall radiates heat into the house through the night as it cools. There are some variations with holes top and bottom to get a convection current going etc but basically it is a fairly simple idea. If you already have masonry exterior walls, it could be retrofitted to the outside of the house - especially the southern side.

A cold winter and the prospect of higher heating costs in the future makes me think of these things these days so I am hauling out the material I have acquired in the past. Probably would make more sense to build a new house rather than consider retrofits but my wife is not interested in moving.

Randy

Figment
02-13-2007, 09:33 AM
Maybe it is the difference between commercial and house bilders

I've gotten the blank stares on commercial and residential jobs. I think it's more likely to be a regional thing. Midwest standard practice is concrete and masonry structure (or, so I'm told), vs here in the northeast it's steel frames with masonry as simple infill or veneer.

Randy, you're right, you'll get more bang for the buck in a new structure. In order for that trombe wall to be effective, it needs to be oriented to the proper exposure, the rest of the house has to be set up to take advantage of the convection, and to avoid bleeding all that heat back out to the night sky, those windows need to be absolutely top-shelf stuff. Then you need some elegant means of keeping the sun out in the summer, etc. It'll be tough to get your nickel back on a retrofit.

I think that sometimes in these discussions of the virtues of thermal mass we lose sight of what thermal mass actually does. It resists rapid change in temperature. It doesn't generate heat, or hold heat, or distribute heat, all it does is slow the rate of change. The BTUs still have to come from somewhere, and you still need to keep them in the building.