[Greenbuilding] Build tight, ventilate right

[Nick Pine]

"Robert Tom" <ArchiLogic at yahoo.ca> wrote:

> If by "simpler exhaust fan" you mean exhaust-only, passive-inlet 
> ventilation strategies (EOPIVS) ... testing done about 10 or 15 years 
> ago here in Canada showed that EOPIVS do not work in all but the most 
> mild Banana Belt locations in Canada, do not work in multi-storey 
> homes and do not work in homes over ~1600 sf.

Why not? What were the problems? Got any references? IIRC, an exhaust 
fan qualifies as a "mechanical ventilation system" in Canadian codes.

John Straube <jfstraub at civmail.uwaterloo.ca>

> Once you have an airtight house and quality (read efficient) 
> ventilation system, natural ventilation does not really save a 
> worthwhile amount of energy in houses but causes all kinds of 
> challenges for construction design and operation while remaining 
> unreliable.
> In large buildings, natural ventilation may be worth the effort, but 
> in a typical SFH, hardly.

"Natural ventilation" as in air leaks vs exhaust fans?

Nick