Code Question ~ HRV

[bnther44]

I'm not sure that this is the correct forum - so moderators please move if I'm off

I'm breaking ground on a new build, hopefully next month. For 'approval' reasons, the primary source of heat for the home will be mini-splits with a pellet stove as a backup. (That's not how were planning to run things, but for the sake of others - that's our story and we're sticking to it!)

The HVAC subs that I've been contacting for quotes have been, by in large, less than cooperative. They'll sell me a conventional heating system or even a Geo-thermal system, but no mini-splits and apparently pellet stoves are for morons.

The latest grief has been over fresh air in the home. According to them, code dictates that fresh air be brought into every 'sleeping room' in the house. Energy.gov lists 4 different types of 'whole house ventilation' but does not say anything about the need to deliver it to every room. In fact, the ventilation that I was initially planning is the exhaust setup - Panasonic bathroom fans - which, according to Energy.gov is ideal for colder climate.

Can anyone comment on this?

Kalamazoo, MI

 

[Knots]

I have no idea what the code is. I just built a house here. The ERV pulls from the two bathrooms and pushes air into the house in one vent in the dining room. I have a fairly open floor plan.

 

[Typ0]

Try and contact the people who sell and install the stoves you want in your area. HVAC people are going to balk because they won't be able to get the work out of you they want to do a job.

 

[Typ0]

The other thing is your local building inspector would be the person to know the codes in your location.

 

[bnther44]

I have no idea what the code is. I just built a house here. The ERV pulls from the two bathrooms and pushes air into the house in one vent in the dining room. I have a fairly open floor plan.

That was my original plan. Can I ask what kind of fans you're using?

 

[bnther44]

The other thing is your local building inspector would be the person to know the codes in your location.

I hadn't even thought of that. Thanks for suggesting it. I kept trying to look it up online...unsuccessfully I might add

 

[Ashful]

It's a miracle those of us living in pre-code houses aren't all dead. [emoji12]

What's an ERV?

 

[Knots]

It's a miracle those of us living in pre-code houses aren't all dead. [emoji12]

What's an ERV?

I hear you. My new house is so tight that I have to have air transfer. My old house was so loose that it would get dry as a bone in there during the winter. The new house holds moisture, so I have to have the transfer system. It's really just an air-to-air heat exchanger that tries to retain some of the heat when it sends stale air out and pulls fresh air in.

Energy Recovery Ventilator.

 

[Knots]

That was my original plan. Can I ask what kind of fans you're using?

It says "American Standard" on the cover, but the instructions say "Trane". The model number is a mile long. It's one of these three:

http://www.coolingunlimited.com/fil...rican-Standard-Energy-Recovery-Ventilator.pdf

My house is 1400 sq ft. Here it is without the ducting:

 

[Ashful]

I hear you. My new house is so tight that I have to have air transfer. My old house was so loose that it would get dry as a bone in there during the winter. The new house holds moisture, so I have to have the transfer system. It's really just an air-to-air heat exchanger that tries to retain some of the heat when it sends stale air out and pulls fresh air in.

Energy Recovery Ventilator.

I remember woodgeek setting me straight on this before, but I still honestly don't understand putting enormous effort into a house to make it as tight as a plastic baggie, and then purposefully ventilating with outside air. Seems there might be some ideal passive air exchange level, which might be less costly than the current methods of sealing tight and then venting.

 

[Typ0]

I hadn't even thought of that. Thanks for suggesting it. I kept trying to look it up online...unsuccessfully I might add

Codes are pretty standard but each municipality has their ins and outs too. They are a good source of information for this as they know the local wood supply, temperatures, winds ... all the variables that will change around the country.

 

[bnther44]

It says "American Standard" on the cover, but the instructions say "Trane". The model number is a mile long. It's one of these three:

http://www.coolingunlimited.com/fil...rican-Standard-Energy-Recovery-Ventilator.pdf

My house is 1400 sq ft. Here it is without the ducting:
View attachment 153714

Thanks for the info!

 

[bnther44]

Codes are pretty standard but each municipality has their ins and outs too. They are a good source of information for this as they know the local wood supply, temperatures, winds ... all the variables that will change around the country.

I'll look into that.

Something that I'm wondering, is there only one person - kind of a state ordained individual - that signs off on a new house? Or can anyone who has a license do the final inspection and give me legal permission to live there?

 

[Typ0]

usually you are supposed to file the plans for the home with the municipality. You haven't done this?

 

[bnther44]

usually you are supposed to file the plans for the home with the municipality. You haven't done this?

We've got a lot done - well & septic permits, driveway, temporary electric...but we haven't filed with the township yet. Part of it is, we want to know the numbers before we sign with the builder - kind of a cart and horse thing. I'm supposed to meet with the builder this week, but I still don't have the mini-splits hammered out yet. Plus, whomever they're using for final inspection is saying the pellet stove can't go in unless it has a thermostat on it...??? The Harmon's do, so no big deal, but it makes me wonder if I'm being given some bad info.

 

[Knots]

I understand what you're saying, but how what are the details of the passive system? How would it work?

 

[ironpony]

I remember woodgeek setting me straight on this before, but I still honestly don't understand putting enormous effort into a house to make it as tight as a plastic baggie, and then purposefully ventilating with outside air. Seems there might be some ideal passive air exchange level, which might be less costly than the current methods of sealing tight and then venting.

yes, it is called build a normal house and let it breathe naturally.

 

[ironpony]

there are code rules and what the inspector wants (God complex) he usually wins.

 

[Knots]

It looks like people have some strong opinions on this. I'm gonna slooooowly back away from the thread....

 

[Ashful]

Sorry about that, Knots, if your comment was directed at me. In my case, I was posing an honest question, with no strong opinions on the matter. Always interested in learning. I should have not derailed this thread, though. My apologies.

 

[bnther44]

It looks like people have some strong opinions on this. I'm gonna slooooowly back away from the thread....

This coming from the Minister of Fire?

 

[Knots]

This coming from the Minister of Fire?

Not my choice - given by the website! Hang in there and you'll join the ministry too!

 

[bnther44]

Not my choice - given by the website! Hang in there and you'll join the ministry too!

LOL

Quick question. I didn't see any square footage mentioned in the 'American Standard/Trane' manual - though they did make the effort to write two pages explaining their limited warranty. You said your house was 1400' - is that with the basement or over top of the basement? I put out some emails yesterday regarding my code question, but haven't gotten any replies - holiday and all. My first instinct is have a setup similar to yours - in at the kitchen, out at the bathrooms. I would think that would satisfy code, but as someone else mentioned - rather passionately - this is relative to the mood of the final inspector.

 

[Knots]

Let me just say that I'm not a spokesperson for the ERV industry. I don't really like having another system. "Simplicity is the ultimate sophistication" said Da Vinci.

I'm just a guy who built a house recently and had a lot less time to engineer than I would have liked. I did the best I could with the time and energy I had to direct to it. New job with lots of travel, elder care stuff, moving - it was crazy.

So, starting with the wood stove in the center of the basement, I decided I wanted good insulation (if you want to enter into a conversation that rivals politics and religion, talk about insulation on the building forums). The factory offers the expanding icynene foam. It fills every nook and cranny. They also caulk all the electrical outlets, and plumbing penetrations before foaming. Sounds good. Do it. Make it 2x8 walls too since it's only 1600 more.

They also add 3/4" of foam under the dry wall to insulate the studs some (studs are around R5 or something). Yay - more insulation.



Then I want good quality vinyl windows since I plan to be in this house a good long time. What do you know? Good windows are pretty tight too.

At this point what do you do? How do you engineer in just the right amount of passive air? Not too much (cold) or too little (air quality). Maybe traditional stick build would have done it - I dunno.

Well - the ERV goes on the list. The doors fit good. All the weatherstripping is brand new. Hell - even the garage doors fit tight.

So - I don't like having the ERV, but here are the positive things:

1). I have a 1400 sq ft house with the stove in the basement and 2 garage bays under and an attached garage at the end. It's looking like a little over 2 cords of mostly soft maple is gonna keep the place toasty warm through a cold Maine winter - except for about two weeks worth of days where I'm not home and the propane keeps it at 60. It doesn't seem to matter whether it's cold or cold & windy. There's no icicles hanging off the roof.

2). I control the amount of air that comes in the house. Just enough to keep it fresh inside. It's not wicked dry in here like it was in my last house with the oversize wood stove and the leaky windows.

3). I transfer the air during the warmest part of the day and I recoup some of the heat before it goes out. At night, when it's really cold I don't let any air out of the house.

So - I don't like having an ERV, but going after the insulation led me there.

 

[Knots]

Here's the house. The main floor is 1400.


The foundation has 4" of foam too. I live in a cooler.

The factory was doing a 2x10 house for someone in Canada when I was there.