Click here to read more articles about Letters
This article originally appeared in the March/April 2009
issue of Home Energy Magazine.
March 09, 2009
How Tight Is a Passive House?
I love your magazine and Web site. You inform me about cutting edge technology for advising, building, and renovating—backed up by tests and studies—it isn’t guessing. That is why I was troubled by your recent sidebar on a Passive House (“First U.S. Retrofit to Passive House Standards,” Nov/Dec ’08, p. 25). Your standards for an airtight house are minimal at 0.6 ACH. For EarthCraft and Energy Star standards we are looking for 0.6 ACH (natural) in a renovation. We are looking for 0.35 ACH in a new house. An ACH of 0.6 in a house is not tight by Energy Star standards or by me for new housing. I do have an engineering degree, but I am recognized for my common sense in building applications to obtain cost-effective energy efficiency. I say this because I don’t want you to think I am just finding fault with numbers. Keep up the good work.
Hampton Roads, Virginia
Author and architect Nabih Tahan replies:
I think that you are confusing natural airtightness—ACH (nat)—with airtightness under pressure. The Passive House requirement is 0.6 air changes per ...
To read complete online articles, you need to sign up for an Online Subscription.
Once an order has been placed there is an automatic $10 processing fee that will be deducted with any cancellation.
The Home Energy Online articles are for personal use only and may not be printed for distribution. For permission to reprint, please send an e-mail to email@example.com.