[Greenbuilding] insulation vs. air sealing

[Futureship]

Good question ? What are the conditions in the attic that would 
Merit ventilation after air sealing 
And insulation ?

On Oct 3, 2010, at 1:27 PM, 
David Wentling 

> 
> "With the airseal measures in place, and the moisture contribution from 
> ex-filtration to the attic eliminated, the question is do you need to ventilate?"
> 
> David Wentling
> 
> From: Futureship <futureship0000 at hotmail.com>
> 
> 
> I have a question with regard to 
> Your results:
> 
> In the first case you described that "Results were 15% higher energy usage with 
> 10% greater leakage."
> 
> How does a blower door measurement
> Tell you 10% greater leakage? The 
> Blower door measures holes in 
> The building envelope . Assuming no
> Air sealing was done the blower door 
> Would not measure a 10% greater leakage. I would argue the increase in stack 
> effect In this case caused an increase in pressure thru the same holes therefore 
> causing more airflow thru the same holes. 
> 
> 
> 
>