[GSBN] Suicide by ventilation (was Re: Airtightness and ventilation)

[RT]

On Sun, 24 Mar 2013,

(1) an old (by his own admission) bug-ger (pun intended),
      a  Mr. North from the Far South cited the following:

http://www.ipsnews.net/1996/06/architecture-zimbabwe-termites-inspire-new-office-complex/

One of the things that I learned when still just a student in architecture  
school in the previous millennium , was that if you spent most of your 4-6  
weeks project time partying instead of actually sweating out the design  
details day and night hunched over your drawing table, and then pulled a  
few all-nighters just before the deadline to whip up some snazzy-looking  
drawings that were "complex" (read: "confusing")  enough that no one would  
admit to not understanding what they represented ... and accompany the few  
sketchy drawings with an even more "complex" verbal presentation to the  
critique panel, chances are that you'd end up with a panel of critters  
fawning over your design, trying to outdo each other in interpreting what  
the design is doing and subsequently get a very good grade on that project.

Back in the day, we called it "Bamboozling the Critters".
I'm sure the same still goes on in architecture schools world-wide.

That is to say, architects are encouraged to be Bull-$#!+ters  
Extraordinaire in order to play The Game well out in there in the world of  
developer towers and mega malls.

One notes in the article cited above, when describing how the building  
actually worked, the following was written:

"Basically, fresh air is pulled in by rows of big fans 10 meters above  
street level

  ... The air is changed twice per hour during the day and seven times per  
hour at night,
      using larger fans to speed cooling."

So while the archi-sales schtick claims that the design is emulating the  
local termites' natural systems design ingenuity , it's really just  
another commercial complex utilising night-cooling not unlike those that  
appeared in the US in the mid-80s , having very little if anything to do  
with termite-think -- in short, there's some "bamboozlin' go'in on" there  
IMO.

OTOH, if the commercial complex had been designed and built as an  
earth-sheltered underground facility out of reach of the Zimbabwean sun,  
I'd wager a box of Tim Horton's doughnuts that it might more resemble the  
passive natural ventilation designs that termitenginoids might create.

However, one of the problems with termite design is that termites have to  
deal with clients who do laundry, take showers, wash dishes, cook pasta,  
sweat while gyrating on exercise equipment to burn off excess fat from  
too-cushy lifestyles, etc.

					*

and
(2) Wild Bill-bob wrote:

> I've been told that there is strong evidence that depressurizing a 
> building not only causes leakage through the walls, drawing incoming air 
> across the dead squirrels in your attic, gas cans in your garage, and 
> lord knows what in the walls themselves, but can also pull outdoor 
> pollutants (fertilizers, pesticides, etc) in from a surprisingly long 
> distance - over 100 ft.

... in short, not unlike a ventilation strategy which would have you take  
a pair of boot socks that you've worn inside of your Wellingtons for the  
past 40 years or more (ie the service life of even the most crappily-built  
house)  and slap them over your nose and mouth to breathe through.

The reality is that infiltration generally takes place below the neutral  
pressure plane (NPP) during the heating season and above the NPP during  
the cooling season. (This is explained quite well in the ASHRAE Handbook  
of Fundamentals ). There was some childhood joke whose punch line was  
"Now, switch !" a joke whose puerile intention was to elicit a disgusted  
"Ee-ee-wwwww !", a joke that would seem appropriate here but fortunately,  
I don't remember how it went.

Unless you can take your building's thermal envelope materials and chuck  
them into a laundering/drying device every few weeks, would you really  
want all of your ventilation air passing through that "old sock filter"  
before reaching your respiratory system ?

But that isn't the worst of it.

If in winter, with your exhaust-only/passive inlet systme (EOPIVS), you're  
really exhausting indoor air at such a high rate as to move the NPP up to  
the ceiling (ie replacing the entire volume of conditioned indoor air with  
outdoor air several times per hour and having to burn no small amount of  
fuel to heat that incoming outdoor air (which could easily be 40 degrees  
colder than a person would normally be comfortable being subjected to )  
back up to comfortable temperatures) ... what's to prevent your  
short-circuiting the chimney that's trying to dispose of the lethal  
combustion emissions as a result of your excessive fuel burning ?  --  
essentially mimicking the same technique that I'm told was used by some to  
commit suicide or dispose of unwanted spouses & pets.