[Strawbale] re re. Re: PEX, Concrete Slab, Fear of Death (by contractor)(Speireag Alden) (Speireag Alden)(Speireag Alden)(Speireag Alden)

[Michael K. Lough]

∆ Speireag said

a layer of 8-inch block (Kachadorian-type floor, later
 
sealed up; bad decision)

∆ OK Youve done it again. I just looked up
Kachadorian and had a Eureka moment It seems like a
winner but you say you followed his example and
installed his floor system but now its sealed up and
you regret it? PLEASE a little more detail?
     
     
     
 The PEX is two to four inches down in the earthen
layer, laid on  
top of the blocks.

∆ Initial reaction to this configuration might
be that the blocks wicked heat from the pex which was
then diluted too much by the air flow or that the air
flow was not in NH sufficiently reliable to move the
heat around and the blocks were too massive and
absorbed too much heat?


 
     Probably.  But remember that I'm experimenting in
this phase  
with an earth-coupled house, 
so I expect to be using solar heat to  
warm the earth under that R-20. 

 ∆I think earth coupling means nothing
insulative between the planet and the floor of the
building ?  R20 would effectively insulate the earth
from the interior? Any rise in temp of the earth under
the building as a result of installing fan insulation
around the outside perimeter of the building and
berming perhaps would not appreciably change the
interior temp above the R20 then??
I really hope I have this wrong
 

 
 
 So if things work, the temperature  
differential across that R-20 will be less than it is
in most  
situations. 

∆Did you ever find any  data to support  this
speculation?




     If I weren't going to do this earth-coupling
experiment, I think  
I'd go to R-30 as a minimum.  After all, I've probably
got about R-35  
in the walls, and I've got R-56 to R-60 in the roof.

∆ Right. Prudence I agree with. I take it the
blocks would be history but I must confess the idea of
harvesting heat from a hollow south facing block wall
in a sunspace during winter and blowing through
channels under the floor to the North wall somehow
seems to make sense as does blowing heated attic air
into the main house or into the sunspace. Perhaps this
far North its not worth bothering with? It certainly
seems like fiddling about too much on a day like this.
Wednesday 11th Jan 


∆what evac tubes did you buy and why?
 
Apricus tubes.  I got a good deal on them, so that
they were  
price-competitive with a flat-plate collector of
roughly equivalent  
output.

 
 
 > Got it, and the hot tap water once used could
return
> still hot through the storage tank before going off
to
> a septic system or similar or even to a "cooling
off"
> holding tank buried below a greenhouse (before it
> flows out to a sump in the garden below the frost
> line). Or to a metal tank in the space as a sort of
> radiator.

     It will flow out a long drain pipe which runs
through the  
greenhouse.  I'm not planning on installing a GFX.

∆The  flow will be unimpeded? Why not slow it
down with a tank in the floor? Concrete block tank
waterproofed inside with insulation around outsides
buried with siliconed sheet of copper or steel on top
open to greenhouse? Insulated in Summer with different
lid.




 

     I haven't chosen it yet.  I may build a plywood
enclosure and  
line it with EPDM.  However, if I'm going to rely on
thermosiphon at  
all, then I may need a tank with pipe plumbed into the
sides or  
bottom, rather than pipe running into the top of an
unsealed tank.

∆I have googled around and the EPDM tanks look
like they will work if one is careful
 Other tanks are
pricy though?  I think xps insulated concrete is the
answer
 sad to say perhaps 
but you can position the
in and out pipes accurately for thermosyphoning?   

 
Michael Lough

 


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