• Welcome to the new and improved Building Code Forum. We appreciate you being here and hope that you are getting the information that you need concerning all codes of the building trades. This is a free forum to the public due to the generosity of the Sawhorses, Corporate Supporters and Supporters who have upgraded their accounts. If you would like to have improved access to the forum please upgrade to Sawhorse by first logging in then clicking here: Upgrades

2015 IECC/IRC Mandatory Blower Door Testing

That worked, that's a HRV, what it it's 100° outside? How does an ERV work and when do you use that? In moderate climates do you install both a HRF and an ERV?

A lot of commercial buildings from the 70s have no openable windows and constant blowing air, I have an engineer located in one of those and I hate to spend time with him with the constant air blowing, I once belonged to gym and they had three of those large 3' diameter fans behind the stairmaster section, women were constantly turning them on and men were constantly turning them off, one guy announced that he was quitting and joining another gym, I asked him why and he said: "One word, fans", I understood.
 
HRVs just recover sensible heat - the heat that shows up on a thermometer - ERVs will recover both sensible and latent heat - basically humidity. Generally you guys would be looking at ERVs there and we keep our HRVs up here. The house here that recently blew a .5 ACH has a unit that is on most of the time. It is a low velocity unit that you cannot hear (I'm only 31, my hearings still fairly good) and cannot feel a draft. it's a lot more expensive that the unit I showed your, but even those units aren't really noisy. When I'm doing a final inspection I can turn one on and you can hear it if you try to. As far as a draft, you won't feel one unless you hold your hand within a couple inches of it.
 
As far as where the line is...I don't know. Someone who is much smarter than me will probably dream up some way of figuring that out, but it's probably the same line where you switch the vapour barrier from the inside of the house to the outside.
 
Last edited:
How many HRVs & ERVs will last the life of the house? Anything mechanical fails after a while, and few will be repaired when they do.
 
We have companies that just do that. We aren't a large population area by any means, about 20000 people. He have a contractor with a couple employees who just do replacements.
 
How many HRVs & ERVs will last the life of the house? Anything mechanical fails after a while, and few will be repaired when they do.

It appears that most of these energy and green requirements drive maintenance costs up, insulated homes rot out a lot faster than uninsulated homes, multi-pane windows have to be replaced an average of every 20 years, I had a friend tell me that he was spending an average of $6,000 a year replacing the IG units in his 20 year-old home, he asked if they were saving that much energy? I had to tell him no, that multi-pane windows don't save money, he is spending money to "save the planet".
 
That's really easy to say when you don't live somewhere that when people buy one of the uninsulated homes, they have to choose between being hungry or cold.
 
  • Like
Reactions: JBI
That's really easy to say when you don't live somewhere that when people buy one of the uninsulated homes, they have to choose between being hungry or cold.

Don't buy the uninsulated home?.....The biggest part of the energy code I agree with is the posting of the predominant R values....At least that way people can shop apples to apples...
 
Top