[geeks] air condititioning, tolerances, and general stuff

[Greg A. Woods]

[ On Thursday, June 27, 2002 at 13:00:02 (-0500), Bill Bradford wrote: ]
> Subject: Re: [geeks] air condititioning, tolerances, and general stuff
>
> Seriously, after they put 3" of insulation up in the attic
> (making it go from R10 to R30), without the new AC even hooked
> up, its just about as cool as it was with the old unit going 
> full blast.

Hmmm.... I've heard other people who've had AC installed talk about
getting their attic insulation beefed up too, but I've always wondered
why.  Doesn't heat rise?  (hot air certainly does!)  Surely you don't
have any way for attic air to get into the rooms, and I doubt your
ceilings are that great a conductors of heat, so what gives?  Do your AC
books talk about any of the physics and engineering of this
"phenomenon"?

Luckily, for winter heat conservation, there is some insulation in the
ceiling of our little 1.5 story (not all in the neighbourhood do as
evidenced by the snow melting on the north sides of some of them when
it's below freezing).  I had to go up there into what's no more than a
crawl space for an attic the year before last, in the summer, to get the
squirrels out -- they'ed broken through the screening of the roof vents
and were making it hard to sleep with all their scampering and rolling
of nuts, etc.  It was damn hot up there!  Though once I got the nest
material out of the vents things improved noticably and I could breath
once again.  Our ceiling isn't exactly cold to the touch, but it's not
noticably warmer than interior wall surfaces either.  Mind you we've got
pretty thick wall/ceiling coverings:  normal 0.5-inch plaster-board
"lath" and then real plaster on top of that....

-- 
								Greg A. Woods

+1 416 218-0098;  <gwoods at acm.org>;  <g.a.woods at ieee.org>;  <woods at robohack.ca>
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