Ventilation concerns - HRV vs fresh air intake


Old 10-10-17, 10:52 AM
Thread Starter
Join Date: Oct 2017
Location: usa
Posts: 4
Received 0 Votes on 0 Posts
Ventilation concerns - HRV vs fresh air intake

We are designing and building an ultra tight heavily insulated house. Our air exchanges per hour are estimated as being between .5 and 1.0. The walls are ICF R-28 with R60 ceilings. We are located in the desert southwest where our average humidity level is 16%. I have received differing advice on mechanical ventilation. One party recommends the installation of a HRV system. The other party says that just putting a fresh air intake to the air handler would be sufficient. Is it advisable to go thru the expense of engineering and installing a HRV?
Sponsored Links
Old 10-10-17, 01:52 PM
airman.1994's Avatar
Join Date: Dec 2005
Location: VA
Posts: 5,795
Received 8 Votes on 8 Posts
Unless your temp is around 65-75 year round a HRV would be the best option
Old 10-10-17, 03:14 PM
Join Date: Oct 2008
Location: New England
Posts: 10,523
Received 37 Votes on 34 Posts
Not an expert on these but my understanding is that an ERV recovers heating or cooling energy while an ERV does the same plus recovering some of the moisture. Now, in winter the incoming cooler air will be dry as dust so allowing it to pick up some of the exiting moisture seems good. Not sure how the moisture transfer would affect your summer conditions. But in both cases the moisture exchange captures some of the energy being exhausted.

As for instilling either an HRV or an ERV vs adding a fresh air intake you have to consider where an equal amount of air will be going out? Assuming there is sufficient leakage area then that air will pass through some unknown cracks and crevices. When moisture and condensation are part of the issue then random ventilation can be a problem, depositing moisture inside walls, maybe not yours.

Designing for a well insulated very tight home I would definitely recommend an air exchange system. Beyond energy and fresh air they offer selective exhaust from stinky areas and fresh air to where you will enjoy it. In some environments they alos permit filtering of that fresh air. Doesn't sound like your air will need that.

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Thread Tools
Search this Thread
Ask a Question
Question Title:
Your question will be posted in: