The 2018 has specific requirements for exhaust ducts and specific requirements for clothes dryer exhausts. You'll find them both in chapter 15 of the code. Your dryer exhaust should be as short as possible and the vent termination should be easily serviceable if possible. Putting it on a roof--particularly in a climate zone with lots of snow is not a good idea.

Thanks so much. I was concerned with the use of flex duct because I saw smooth interior metal duct requirement called out in the 2018 code. I also think the dryer exhaust run is too long per code.

I didn’t even think about the potential problems with it exhausting on the roof. There are also 2 other exhausts near it on the roof. I believe they are bathroom exhaust vents.

Is our builder legally liable to bring our home into code compliance?

"Is our builder legally liable to bring our home into code compliance?"

Well, the house won't pass inspection and you won't get a certificate of occupancy if it doesn't!

That's the problem...several things got past the inspectors and we DID get the certificat of occupancy. I have had several converstaions with our local building inspectors and they said they don't really check a lot of things (R value of ducts, vent size code requirements for indoor combustion air intake, length of dryer duct, material of ducts...they don't get on ladders to inspect anything - only if they see something obvious is it noted) and they assume the contractors install correctly and to code. We have even discovered a duct boot / register covered with drywall.

If our HVAC system heated and cooled properly we wouldn't even be investigating these other things, but we've done a deep dive since the system doesn't work right.

This was supposed to be our dream home - very sad.

The quality and time allotted to residential inspections varies from one municipality to another. It's rarely, if ever, a truly comprehensive check to ensure compliance.

Check with your attorney regarding your state's contractor laws. Here in Virginia, builders are obligated to correct anything that doesn't comply with the building code for a period of three years after a certificate of occupancy is issued.

Thanks Johnson Brothers Contracting.

There is a way to run it with just one 90 degree bend (as it exits the laundry wall into our garage and then only about 10' to the exterior. We would probably need to build a little bulkhead for the duct run (or just have it exposed since it's a garge). We could put a garage shelf over it so so the exposed duct (or duct bulkhead) doesn't look weird.

Sounds like this may be worth pursuing if it would indeed be a fire hazard - do you agree?

Thanks Charles Ross Homes!

Unfortuantely, we have been forced to retain attorneys here in Indiana. We are just trying to do a lot of the investigation ourselves given the $350/hour attorneys fees :(

I appreciate the information.

By all means reroute the dryer duct to make it shorter and to make the exhaust vent accessible for cleaning and maintenance.

I feel so dumb not paying attention this. We were so busy selecting cabinets, flooring, tile, appliances, fixtures...we just assumed stuff like this would be done correctly and to code!

Our dryer exhaust has a screen on it too, which is not to code. I'm not sure how to tell if it has a backdraft damper. I also don't think it's the right type of exhaust hood for a dryer vent.

It's on a steep roof - not sure how we're going to access this or clean it! You can see how clogged it is already.

I hope my builder is liable to bring this into compliance with 2018 IRC which Indiana has adopted.

The code only protects home owners to the extent that plans are reviewed prior to, and routine inspections by code compliance are conducted at key milestones during construction. If your area doesn't have a building code or appropriate inspections to enforce the code, you're getting short changed. That's an issue to have a chat with an elected official about.

Wow! Definitely a hazard, as well as gagging the dryer. That screen needs to be removed. As a temporary sop to deal with the lint that may be in the ducting, one might consider using an electric leaf blower (not a gasoline one!) to attempt to blow out the lint accumulated in the long duct, but I think the screen will need to be removed first.

I wouldn't wait for the legal dust to settle before doing this. If the builder won't react quickly, perhaps a roofer could be found to send someone up there to pull the screen. Send the bill to the builder. If there is an accessible attic, then there may be a way to access the roof vent from inside.

The reasons for short dryer duct runs includes the pressure loss limits of the dryer blower. Flow rate will quickly drop with back pressure. Damp lint can "condense" on the ducting, which shouldn't be flex duct as we know because the corrugations become prime starting locations for lint accumulation.

"and (inspectors) assume the contractors install correctly and to code"

If that were the case, we wouldn't need building inspectors!

Family havc businessmfor 50 years. personally been installing since 1995

1-dryer can not have screen should be as short as possoble depending on code. somtime require booster and lint trap on long runs must have damper

2- In PA we can not have concealed flex duct as shown. for many years. Photo shows lazy install. Should be all rigid metal, R8 wrap and duct air tested due to location

Sorry- also……you can notch that load bearing 2x6 wall with correct striker plate and eliminate that ”45” degree framing…..odd

There are a lot of "odd," incorrect, and lazy stuff we are discovering on our home. We tried to access the screen yesterday, and the roof is so steep in that area.; it is too dangerous.

IRC 2018 says (M1502.1) "Clothes dryers shall be exhausted in accordance with the manufacturer's instructions."

My GE dryer instructions says "termination should require little or no maintenance to prevent clogging." and "provide access for inspection and cleaning of the exhasut system, especially at turns and joints."

There is no way that it is OK to have the "termination" on a very steep roof.

The duct run is probably slightly under 35', but when you subtract 5' for each 90 degree bend and 2.5' for each 45 degree bend, there is no way it meets code. It looks like there are 2 - 45 degrees bends and 1 - 90 degree bend at that weird 45 degree framing as the duct runs through our garage ceiling. There is another bend as it turns upward to exit the roof. And, the duct appears to be flex duct. I guess there is a chance it is rigid duct wrapped in QuietFlex insulation....still, a lot of code violations: long run, roof termination, screen, no easy access for cleaning, possibly no damper...

@ HU-602824186 - Do you have experience with the code requirement for fresh air supply? Our blower door test is less than 5 ACH, so we were told that we need a "fresh air supply."

What are the options to meet the fresh air supply requirement?

We have a continuous fan in our powder room, blowing air out. Bathroom exhaust fans blowing air out.

We have 100K BTU gas furnace and a 76K BTU gas water heater using combustion air from inside our home. We have a fireplace using combustion air. We have a range exhaust hood that can exhaust up to 1200 CFM (with no make-up air system).

It seems we would have very high negative pressure in our home...especially with new "tight construction."

The company that did the blower door test told me that the "negative pressure" situation is how we meet the fresh air requirement..because every time we open a door fresh air is sucked in due to the negative pressure. That sounds like BS. Let me know if you know what type of system woudl be required for "fresh air"

@maxjackjoe Reading make-up air (MUA) related threads here will start you on the path to considerations of how MUA can be inserted into your architecture. Even if you don't run the fireplace, and all your combustion appliances have their own MUA, your kitchen hood will not be moving 1200 CFM. It might move 800 CFM with the house doors open, depending on its duct configuration and its filter system.

What is likely going on (assuming your chimney is not being back-drafted) is that the hood blower is gagged to a few hundred CFM. This will be at the point on the fan curve (see below) where the house negative pressure horizontal line crosses the fan curve.

Operating a kitchen hood and fireplace together requires MUA to be almost perfectly balanced, because a fireplace draft is not very much pressure difference between hearth and outside above the roof. Otherwise, at a minimum, you need to not back-draft your powder room continuous fan system.

This gets to the issues of passive (no blower) vs. active (with blower) MUA system, that I don't want to address until you have absorbed some more background. You can also read the first dozen or so pages of the Greenheck guide at the link for the commercial approach, which is what residential kitchen ventilation attempts to approach within the limitations of cost, appearance, and space.

https://www.tagengineering.ca/wp-content/uploads/2015/02/KVSApplDesign_catalog.pdf

Opaone's document is also worth reviewing: https://bamasotan.us/range-exhaust-hood-faq/

@maxjackjoe,

Your blower door test results indicate that your home is "tightly constructed" i.e., it has a low natural air infiltration (air leakage) rate. When the blower door test results indicate less than 5 air changes/hr at 50 Pa (5 ACH 50), fresh air ventilation is required per section 401.2 of the 2018 International Mechanical Code. The purpose is to maintain indoor air quality for occupant health and safety. This is not a consequence of your combustion appliances utilizing indoor air for combustion nor the lack of make-up air for your range hood. Rather, it's a consequence of the quality of the air sealing in your home.

The need for make up air for a range hood is covered in 505.4 of the 2018 International Mechanical Code; the requirements for combustion air are regulated by the International Fuel Gas Code.

You should consider either an energy-recovery ventilator or a heat-recovery ventilator to supply fresh air. Make-up air for combustion and vented appliances is a separate but related consideration.

Yes- I have experience with blower door

Make up air required on any oven venting going over 400 cfm —-/ with alot of venting house will goninto negative pressure chutnthis door that door slams fire

places cant draft…..ovens, dryers and barhs all going at once

I recommend air to air exchangers on tight homes especially spray foam

This coming summer in PA we go to 3 air exchanges for blower Door. Big increase

for builders.

If your house is that tight you need a interlocked ventalation sysyem to bring air in determined by square footage, room and people etc.…Calcualated

Chris-

Spelling still counts unless you went to school with Jethro Bodine.

That’s fine. I never comment on websites because it’s a waste of time.

I was in a hole plumbing a house and auto correct and tired fingers took a toll on my comment. You’re a funny guy.

I’ll bow out and let you guys that never install anything at all take the reigns.

Thanks for the hate. Hahahaha.

If you want to go toe to toe on a full 25,000 square foot house and prove who is better. Let me know and we can set it up.

It's not hate, HU.

If you're a "pro" then register as such so people can weigh your opinion as a "pro's" opinion. Presentation counts. If your post looks like it's written by Jethro Bodine it's veracity will--and should-- be called into question. Take a look at yours from that perspective.

A fresh air system can affect indoor relative humidity. That said, controlling indoor relative humidity is a primary function of your home's air conditioning system. If the blower door test indicates less than 5 air changes/hr. I suspect your home is both well sealed and well insulated, too--both of which reduce the heating and cooling loads. If your air conditioner is over-sized, it won't operate often enough and for long enough intervals to effectively dehumidify the indoor environment.

Yes, our blower door test was < 5 ACH - required here in Indiana...which seems to mean an air-to-air exhanger (whole house ventilation system) is also required on all new construction in Indiana.

I'm still trying to figure out how that got missed during our inspection process. I looked up ERV and HRV and they are pretty sizable units that someone should have noticed missing.

We have a 4 ton AC for 2400 sqft ranch with 2200 sqft finished basement. We also have a 750 sqft bonus room over our garage that has a 2 ton AC - though we rarely run that since the room is not fully finished. We have poorly designed ducts so the basement gets very low air flow (can't heat above 62 degrees in the winter) and we have had to resort to using portable heaters in the winter and a portable dehumidifier in the summer due to humidity levels near 70%

It's all very sad for a brand new house in which we planned to retire.

I suggest you contact your home's designer and your home builder about the issues and how best to resolve them.

And now, in my twilight years, I find out that Jethro's family name was Bodine not Clampett. This forum is truly a treasure.

The cost of very low air replacement rate is either degraded health due to low IAQ or more expense to try to save heat while replacing the air more frequently. Also, there will be more expense to ensure that cooking effluent (including gas combustion products if applicable) are fully collected and expelled from the residence. I know of no practical residential heat exchanger for cooking effluent, so the heat that is believed to be saved by the higher level of house sealing will be somewhat or significantly -- depending on cooking habits -- reduced by cooking.

I believe @opaone and a few others have addressed IAQ w.r.t. cooking in this forum. A search on author and "IAQ" should find these comments.

Obviously indoor air quality and health are the primary concern. I have had what I had believed to be 3 episodes of food poisoning in less than a year of being in this house. I'm in this house 22+ hours a day, and we almost never open windows due to dust from surrounding construction sites.

I can't help but wonder if my health issues are related to indoor air quality...We also had our ductwork flooded during construction from a roof leak that went unaddressed for months. I wonder if the remediation of the water damaged ductwork was thorough and complete?

I appreciate everyone's comments and expertise!