[Strawbale] PEX, Concrete Slab, Fear of Death by contractor

[Speireag Alden]

On 2008, Jan 09, at 23:09, Michael K. Lough wrote:

> 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?

     You can't clean it.  What happens when mice get into it?  (Which  
they did.)  You want to circulate air through that, even though it's  
pretty much always going to be dry air?  I decided that it wasn't  
worth it.

     When it was working, it did perceptibly circulate air when the  
floor was heating, drawing it in on one end and venting at the  
other.  So it worked to transport heat from the floor to the living  
environment.  But the floor radiates anyway, and that turns out to  
work well enough.

>>      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?

     Yes.  The original house, where the radiant floor is, has R-20  
under the floor.  The addition, which I am building now, and which  
will not have a radiant floor, is earth-coupled.  You don't earth- 
couple radiant floors, unless you're heating them only with totally  
renewable energy.

>>  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?

     "Speculation" seems a bit harsh.  If you warm the earth, even a  
little, then you'll lose less heat to it.  That's all I said, above.

     The question is whether it can be warmed /enough/ to matter,  
using only solar input.  I'll tell you in a few years.

>>      [Drain water] 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?

     Lots of cost for excavation and installation of a tank, for very  
marginal gain.  Drain water is typically going to be only around 20°C  
to 27°C by the time it hits the greenhouse.

-Speireag.