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

[Speireag Alden]

On 2007, Dec 27, at 00:02, Shody Ryon wrote:

> When we had this conversation before, someone said
> they cracked the windows open in the bed rooms because
> it was warmer than they liked at night. Because I like
> cold bedrooms, high R value insulation and energy
> efficiency, I would leave the bed rooms unheated.

     You could also insulate around the bedrooms, so that they absorb  
less heat from the rest of the house.

> This still does not address the R value of the
> concrete floor vs wood and the roof insulation which
> is a good topic.

     This is a red herring.  You can make a good floor, with lots of  
R-value, either way.  Both have their pros and cons and might be  
better or worse for specific circumstances.

> I really like warm floors and high air quality so I am
> thinking of either warm water or air warming the floor
> from underneath.

     If you want highest air quality, don't install a heat system  
which will require ducts, moving air, and air filters.  Use water.

> Wood floors would have a much faster
> response than concrete, I assume,

     Not necessarily.  Wood doesn't conduct heat as well.  Thin  
concrete over a good insulation layer will respond within minutes.

> not that the
> temperature would change much, unless the house were
> empty for a large part of the day, correct?

     This is true, and why response time is also a red herring.  When  
the house's temperature is essentially stable, you have plenty of  
lead time to turn heat on.  Response time only matters when  
temperature dives, or you've been away and let things cool off.  But  
in well-insulated buildings with plenty of thermal mass, the  
temperature doesn't dive.  You have plenty of time to turn the heat  
on as needed.

-Speireag.