Thread: Bathroom Exhaust Fans

As I'm approaching the 1yr anniversary of the purchase of a home in NC (constructed in mid-2005), I hired a local inspector to provide an independent assessment of the condition of the home. The builder's warranty expires on July 10th.

One thing the inspector did not check was the performance of the bathroom fans...he checked to see that they worked but did not have an anemometer or other meter required to measure air flow.

What is the code requirement of sizing of residential bathroom fans (I'm guessing 1-2 cfm fan size per sq ft but the ceiling height in the bathroom is 10' so there's lots of volume here)? Our master bathroom fan does not keep steam from forming on the mirrors and clearing the mirrors and shower doors of steam takes 15-20 minutes after finishing the shower.

I've summarized the punch list for the builder with some photos at Open Warranty Issues -Lot 1039 Sconset Village
I hired an inspector based on the advice from this forum...too bad I didn't do so when we purchased the home last year. If you see anything on the list or if I've said anything that is no accurate please let me know.

As to the fan, I have a meter to test it with later this week. Steve D

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Looks like your complaints to the builder should have been mailed from an attorney's office.

Things are still amicable and the builder has a strong reputation in the Carolinas. It's merely a punch list to get the items in under the warranty period.

This is the first time I've ever gone through this process. Is it normal to send post-purchase inspection reports from an attorney's office? SD

Originally Posted by Steve D'Gerolamo

As I'm approaching the 1yr anniversary of the purchase of a home in NC (constructed in mid-2005), I hired a local inspector to provide an independent assessment of the condition of the home. The builder's warranty expires on July 10th.

One thing the inspector did not check was the performance of the bathroom fans...he checked to see that they worked but did not have an anemometer or other meter required to measure air flow.

What is the code requirement of sizing of residential bathroom fans (I'm guessing 1-2 cfm fan size per sq ft but the ceiling height in the bathroom is 10' so there's lots of volume here)? Our master bathroom fan does not keep steam from forming on the mirrors and clearing the mirrors and shower doors of steam takes 15-20 minutes after finishing the shower.

I've summarized the punch list for the builder with some photos at Open Warranty Issues -Lot 1039 Sconset Village
I hired an inspector based on the advice from this forum...too bad I didn't do so when we purchased the home last year. If you see anything on the list or if I've said anything that is no accurate please let me know.

As to the fan, I have a meter to test it with later this week. Steve D

Mechanical fan needs to be 20 cfm continuous or 50 cfm intermittent or greater. Even the cheap ones provide this, I don't think they make them less than this. If you are under the IRC this is all that the builder would be required to install. If the bathroom has a window that opens, a fan is not even required. Room size does not come into play with a bathroom vent fan. Common sense and proper placement however is not covered with the Codes!

A vent fan will not keep the steam from forming in a bathroom. It will help to get rid of the humid air but I have never seen one that can keep up with the amount of moisture that is produced by a shower. About all you can do is to take shorter showers or lower the water temp.

FYI, home inspectors do not test for airflow. Unless you specified this to the inspector this is not a normal thing for inspectors to do. I bet that if you asked 100 home inspectors if they even had an anemometer or knew what one was you might have 5 who would know what it is and only 1 might have one.

Steve
A cursory look at your "fix" list reveals many legitimate problems and some that are not. However, as a consultant I would spend a fair amount of time evaluating your list, but that takes time and time is money. I recommend you retain a qualified construction consultant (code certified) and have him/her perform a thorough evaluation of your new house including everything on your list. Personally I would like to have seen more photos, i.e.; water heaters located in the attic, master-bathroom whirlpool tub, and both the attic and foundation crawl spaces.
PS: I echo Scott's advice.

Originally Posted by Jerry McCarthy

Steve
A cursory look at your "fix" list reveals many legitimate problems and some that are not. However, as a consultant I would spend a fair amount of time evaluating your list, but that takes time and time is money. I recommend you retain a qualified construction consultant (code certified) and have him/her perform a thorough evaluation of your new house including everything on your list. Personally I would like to have seen more photos, i.e.; water heaters located in the attic, master-bathroom whirlpool tub, and both the attic and foundation crawl spaces.
PS: I echo Scott's advice.

I agree with Jerry. A good number of your concerns are very minor in nature and some should have been covered under your contract with the builder. i.e. The scuttle hole attic entrance. This is all that is needed. If you wanted a pull-down ladder this this should have been in the contract with the builder.

You have several good home inspectors in your part of NC that could help. Look for one with experience and knowledge, now is not the time to go cheap. Expect to pay in the area of $175-$225 per hour for an inspector with this type of knowledge base and skill. Based on the size of your home I would say that it would be about a 4-6 hour job for most inspectors.

I did retain an inspector (referenced his name, license number and contact info at the top of the page) and he was the one that caught some of the more serious issues. He charges by the square footage and not the hour...still he spent approx 3hrs doing the inspection and I had a report emailed to me by the end of the day.

Some issues (like a gas leak in the crawl space) have been fixed and are not on the list. I know some of the issues are minor but my wife made me put them on the list. Things like nail pops and drawer slides are covered under the homeowners warranty and are on the punch list.

As to the photos, I'm in NJ right now but will be returning to the home in NC on Wednesday...I'll try to get some detailed photos of the water heaters.
SD

Originally Posted by Steve D'Gerolamo

..I'll try to get some detailed photos of the water heaters.
SD

.
Hey Steve,

To heck with the WH.

WE want to see what you've done with the Garage.

Originally Posted by Steve D'Gerolamo

Things are still amicable and the builder has a strong reputation in the Carolinas. It's merely a punch list to get the items in under the warranty period.

This is the first time I've ever gone through this process. Is it normal to send post-purchase inspection reports from an attorney's office? SD

This might be your Post purchase report, but, You have apparently had some minor issues with the builder that have been inadequately addressed such as the $900 bill for the attic stairs.
The builder has your money and other projects to work on.
Ask him for a face to face sit down. Get him to commit to a time frame for all repairs. Have him put it in writing. and, if his response is less than satisfactory, yes, I'd get an attorney involved.

Nothing like an attorneys letterhead to get your attention.


Edited to add the following;

Look at this post:
http://www.inspectionnews.net/home_i...y-respond.html

Originally Posted by Billy Stephens

.
Hey Steve,

To heck with the WH.

WE want to see what you've done with the Garage.

I won't be tearing apart the garage until I down there full time to see the project through to completion.

Originally Posted by Steve D'Gerolamo

One thing the inspector did not check was the performance of the bathroom fans...he checked to see that they worked but did not have an anemometer or other meter required to measure air flow.

I don't know of any home inspector who checks "the performance" of any fans. That gets way ... WAY ... *WAY* ... beyond what is reasonable to expect a home inspector to check. If you want that done, you either should be asking for an HVAC person, or, a construction consultant leading toward litigation, and then you would need to specify that you would like that checked - WAY TOO MANY other big things to check for to make the best use of your money.

Of course, though, if you want it done, a construction consultant or HVAC person 'can' check it for you. Typically, something like that is only done if you have a specific problem and that is suspect as a cause.

What is the code requirement of sizing of residential bathroom fans (I'm guessing 1-2 cfm fan size per sq ft but the ceiling height in the bathroom is 10' so there's lots of volume here)?

Scott gave the minimum ventilation requirements, and code is only minimum.

Our master bathroom fan does not keep steam from forming on the mirrors and clearing the mirrors and shower doors of steam takes 15-20 minutes after finishing the shower.

You would not want a fan in your bathroom which would be capable of keeping that from happening? I think they are called 747's or something like that.

If the bathroom is large, you would want several exhaust fans (however, one el cheapo builders model at 50 cfm would meet the minimum requirements).

Question: How cold do yo keep the house and how hot do you use the water, for how long? Keeping the house cold lowers the dew point when you use hot water, causing the water vapor in the air to condense on the mirrors and glass more than if those items were warmer. The longer you use the hot water, and the hotter the water is, the more moisture there will be in the air to condense on those cooler items. There is also a good possibility that condensation is forming on the bathroom cabinets too (and you just have not noticed it).

The location of the fan could also be part of the problem. It is only required to be 'in the bathroom', but if it were 'near the moisture source' (i.e., near the shower, but *not* over the shower), then it would be more effective than if located far away from the shower.

Also, if you have a separate toilet room, that requires its own exhaust fan.

As Jerry Mc. says:"A cursory look at your "fix" list reveals many legitimate problems and some that are not. However, as a consultant I would spend a fair amount of time evaluating your list, but that takes time and time is money. I recommend you retain a qualified construction consultant (code certified) and have him/her perform a thorough evaluation of your new house including everything on your list. Personally I would like to have seen more photos, i.e.; water heaters located in the attic, master-bathroom whirlpool tub, and both the attic and foundation crawl spaces."

I see items in those photos which may not have been addressed (or may have been and were just not noted in what was made available to use).

Originally Posted by Jerry Peck

I don't know of any home inspector who checks "the performance" of any fans. That gets way ... WAY ... *WAY* ... beyond what is reasonable to expect a home inspector to check. If you want that done, you either should be asking for an HVAC person, or, a construction consultant leading toward litigation.......

There's a lot of talk about lawyers and litigation here. I'm not going to retain some $200/hr lawyer to fight for a new $80 fan.

The whole purpose of my post to find an appropriate way to go forward to my builder with facts gathered by me and a licensed home inspector for coverage under a New Homeowners Warranty. I'm a firm believer like most of you that a picture is worth a thousand words but data from a reliable scope or meter is useful in troubleshooting a mechanical component.

I have an Airflow TA45 thermal anemometer and can take some measurements but a simple tissue or smoke test will confirm is there is minimal draw.

Your point about the AC (room temp is 73-74F) is an excellent one (I owe you a beer for that one). We have no AC in our bathroom in NJ and the fan does a good job of managing the condensation.

There is a separate water closet (toilet room) and it has its own fan.

Here's the fan I use at home....1320cfm @ 4.4" static pressure. The 1.5hp direct drive motor is isolated from the air flow. Even combustible fumes would be isolated from sparks (arcing) in the motor.

The room also has 400cfm of filtered and dehumidified make-up air from a Thermastor APD. SD

Originally Posted by Steve D'Gerolamo

There's a lot of talk about lawyers and litigation here. I'm not going to retain some $200/hr lawyer to fight for a new $80 fan.

That is understood ... on that one issue, that would be a no-brainer, but, considering your other issues ... ???

You also asked for "What is the code requirement of sizing of residential bathroom fans" and Scott provided that, but, as is typical, minimum code compliance does not produce the results you are looking for.

Minimum "code" and usefulness is not always the same.

The whole purpose of my post to find an appropriate way to go forward to my builder with facts gathered by me and a licensed home inspector for coverage under a New Homeowners Warranty.

And that is a very good starting step, one step that not everyone takes.

Sometimes, though, you need to do more, and at this point you do not yet know what other steps will be needed, and you will not know that until you get the builder's response. At that time, though, you may need to seek other options, options we were suggesting you could use, options only you will know when and how to use them (we are not aware of all of the particulars).

I'm a firm believer like most of you that a picture is worth a thousand words but data from a reliable scope or meter is useful in troubleshooting a mechanical component.

Except that you are not trouble shooting a mechanical component, you will be trouble shooting a system which is not functioning as you wanted, but which is may be functioning as designed and intended.

I have an Airflow TA45 thermal anemometer and can take some measurements but a simple tissue or smoke test will confirm is there is minimal draw.

50 cfm is minimal draw. If the damper on the exhaust fan is open, that fan should hold a tissue up against it. If it does not, then the damper may be stuck closed, or there may be another problem with the duct from the fan, such as the duct being bent back on itself too sharply, partially collapsing the duct, or at least reducing its effect internal diameter. If flexible aluminum duct was used, it likely could be crushed in one area.

I thought Steve and his tribulations sounded familiar! He has been battling this for a while with this builder.
http://www.inspectionnews.net/home_i...html#post22556

Steve, that is one heck of a vent fan for that bathroom! Heck, I bet my wife could suck her hair dry with that thing by just standing under it! Kind of reminds me of a "Tool Time" episode with Tim Allen.

If you do get to the litigation point, Don Lovering out of MA would be a good person to contact. He works in NC as well. Commercial Inspections Massachusetts | Massachusetts Home Inspection | Roof Covering Inspections

Originally Posted by Scott Patterson

I thought Steve and his tribulations sounded familiar! He has been battling this for a while with this builder.
http://www.inspectionnews.net/home_i...html#post22556

Steve, that is one heck of a vent fan for that bathroom! Heck, I bet my wife could suck her hair dry with that thing by just standing under it! Kind of reminds me of a "Tool Time" episode with Tim Allen.

Thanks Scott........actually, that fan is the one in my garage at home for source capture. The big can you see in the photo above is a large muffler to silence any exhaust noise before it goes out the roof.

OK Steve, you are going to have the folks on this site drooling on their keyboards when they see that picture!

Last week somebody posted a picture of hobby airplane being built in a garage and all they could talk about was the epoxy coated garage floor!

Originally Posted by Scott Patterson

OK Steve, you are going to have the folks on this site drooling on their keyboards when they see that picture!

Last week somebody posted a picture of hobby airplane being built in a garage and all they could talk about was the epoxy coated garage floor!

There are some more pictures of this garage bay at Technology & Design Showcase (p4) . You guys will probably find a bunch of stuff I did wrong but at least I aspire to do things right!

Steve,

NICE garage.

Even cooler cars in it.

You have the money and you apparently have the toys. Obviously that is not the exhaust fan for the bathroom. If it were you could certainly vacate the bathroom from the better half that is taking to much time in there. As far as the attorney, gees, I don't even like that word.

There is such a thing as having to much conditioned air pumping into the bathroom. Do you get goose bumps in the bath after stepping out of the shower. Are your windows bulged toward the exterior when the air is on.

You so do not need a lawyer at this point. I for one cannot believe any inspector is recommending this at this point. You are amicable with the builder, keep it that way. Adding another exhaust vent would certainly help with the bathroom vent situation.

There are also glass cleaners that help reduce fogged mirrors.

With all your goodies and apparent money please don't let it cause an OCD situation to take hold.

There is such a thing as over kill.

Just some thoughts and just my opinion.

How fast is fast enough

Originally Posted by Ted Menelly

You have the money and you apparently have the toys. Obviously that is not the exhaust fan for the bathroom. If it were you could certainly vacate the bathroom from the better half that is taking to much time in there. As far as the attorney, gees, I don't even like that word.

There is such a thing as having to much conditioned air pumping into the bathroom. Do you get goose bumps in the bath after stepping out of the shower. Are your windows bulged toward the exterior when the air is on.

You so do not need a lawyer at this point. I for one cannot believe any inspector is recommending this at this point. You are amicable with the builder, keep it that way. Adding another exhaust vent would certainly help with the bathroom vent situation.

There are also glass cleaners that help reduce fogged mirrors.

With all your goodies and apparent money please don't let it cause an OCD situation to take hold.

There is such a thing as over kill.

Just some thoughts and just my opinion.

How fast is fast enough

I design and outfit garages and workshops for private collectors, race teams and others across the country. HVAC (incl fume extraction), electrical, and other mechanicals are a very important part of these projects and I do tend to get a little OCD with regard to these matters. It pisses me off when a high end builder goes all out on architectural details and then skimps on the what you can't see.

I believe Jerry hit identified the problem as too much AC in the bathroom and a wife who takes long showers. We had a problem with the bathroom and I had the HVAC contractor rebalance the 1st floor system and put a little more air to the 2 bathroom registers. In the winter, with the living room thermostat set to 70F and an outside temp of 30F, the temperature in the bathroom was a chilly 56F.

As far as this comment on my punch list, the source was my wife and not the home inspector.

I understand, I always add a little light heartedness (is that a wod?)with seriousness. Besides, we know who the real boss is in most homes (I think its the pretty one)

A few more comments....the guy that did my inspection looked over my punch list and had me pull one of the items... I commented on the lack of ground for the 3 electrical panels. His reply...."The panel does not require a separate ground. This is acceptable to Duke Energy as the neutral is used for neutral and ground to the meter base. Not what I would do but Duke is the ultimate decision maker on this item."

Also, he did not test the T&P valve on the water heaters (I guess based on my past experiences, I'd be reluctant to do so without a replacement at hand)... Having those water heaters in the attic makes me nervous. SD

Originally Posted by Steve D'Gerolamo

I commented on the lack of ground for the 3 electrical panels.

Steve,

"electrical panels"???

Do you mean where the service equipment is? I.e., where the main disconnects are?

Or, do you mean distribution panels which do not have THE main disconnects in them?

The former requires grounding, albeit the three grounding conductors are allowed to be connected together to one system grounding point, made up of all of the available grounding electrodes present.

The latter requires separate grounding back to the service equipment grounds.

Actually the one that we checked that didn't have the ground was a subpanel. SD

Originally Posted by Steve D'Gerolamo

Actually the one that we checked that didn't have the ground was a subpanel. SD

Oh, you work on subs too?

You mean it was "not service equipment", all panels which are "not service equipment" are wired the same way - all require a ground, and all require the neutral to be isolated from ground.

If it was "not service equipment" and did not have a ground, then was it wired with SEC cable (two hot conductors and a neutral/ground outer wrapped around them, with the outer covering around that)?

Or was it wired with a metal raceway to that panel? The metal raceway can serve as the ground - if installed correctly.

- $80 for an exhaust fan for a large bathroom, that's part of the problem.
- For an HI, you turn the unit on and the flapper opens outside, it works. You want performance check, that's not an HI, that's a 'specified system analysis'.
It is not reasonable to make an assumption whether or not an exhaust fan will perform adequately during an HI, since no one really knows how long and hot the showers will be.
- Only a newbie would actually test the T&P. Once you open it you don't know whether it will seal again 100%
People make this mistake all the time. They hire a standard HI to do a standard HI when that isn't what they need. Often times people should be hiring not just an HI but an HI who has the experience to do assessments and detailed evaluations. Especially when the customer, a) knows there are problems and b) dispute among parties is likely. Such services also cost more than an HI for legitimate reasons.
You can blame the HI all you want but considering you are to some extent in the trade industry and admit to being somewhat OCD you appear to qualify as 'a party who should have known better'.

Originally Posted by Jerry McCarthy

Steve
Personally I would like to have seen more photos, i.e.; water heaters located in the attic..........

Took some pictures last week. Not a pretty installation but my inspector didn't note anything other than............

"Operational. Pressure relief valve noted, not tested. Flue vent intact. A water shutoff valve is installed".

Photo links are here...........

http://www.ultimategarage.com/personal/1yrwh1.jpg

http://www.ultimategarage.com/personal/1yrwh2.jpg

http://www.ultimategarage.com/personal/1yrwh3.jpg

http://www.ultimategarage.com/personal/1yrwh4.jpg

http://www.ultimategarage.com/personal/1yrwh5.jpg

http://www.ultimategarage.com/personal/1yrwh6.jpg

http://www.ultimategarage.com/personal/1yrwh7.jpg

http://www.ultimategarage.com/personal/1yrwh8.jpg

http://www.ultimategarage.com/personal/1yrwh9.jpg

Doing the basic inspection, very basic and not a good example of basic because he did not meet the very basic at all.

I will let one of the other folks tear it apart (pictures, report).

My biggest and certainly far from the only is the TPR blowing off into the pan under the WH's. Gees. I would not want to see what happens to your house if it does blow off. (assuming that is the attic over the house)

Thanks Ted....there are 2 levels of finished living space below the water heaters. The builder seems to feel those 6qt (??) pans are adequate since they are plumbed to the drains in 2" pvc. He also feels the expansion tank (1 for both heaters) will prevent these valves from ever blowing.

I know I'm a bit OCD but I figured there had to be a thing or 2 that wasn't right here. The question is if there's anything not up to code that was signed off on? SD

I only glanced through the photos, the thing which struck me was that none ... nada ... of the plumbing piping in the attic was protected from freezing as required above the 32 degree day line, which basically goes from Jacksonville, Florida, through Tallahassee, Florida, through Pensacola, Florida, through ... let's just make it simple - basically follow I-10 across the country, that's not real far off from the line.

Above I-10, protect all piping outside the thermal envelope of the house.

Jerry....I think most of the water pipes are insulated....the 12" stubs out of the top of the heater are not.

For some reason, they use copper for the gas lines here in NC. These gas lines are not insulated.

Originally Posted by Steve D'Gerolamo

For some reason, they use copper for the gas lines here in NC. These gas lines are not insulated.

Okay, then, that is better.

I was looking at the gas lines.

I write up copper gas lines even in attics. Code, no code. There are corrosives to copper in natural gas.

Oh gees (code, no code) I am going to get it. Actually every time I have written up copper gas pipe in an attic and the reasons for such (you will see these reasons in the code, with particular stipulations) it has been replaced. Whether it be because the home owner/buyer asked for it or a plumber agreed I do not know/remember.

Originally Posted by Ted Menelly

I write up copper gas lines even in attics. Code, no code. There are corrosives to copper in natural gas.

Oh gees (code, no code) I am going to get it. Actually every time I have written up copper gas pipe in an attic and the reasons for such (you will see these reasons in the code, with particular stipulations) it has been replaced. Whether it be because the home owner/buyer asked for it or a plumber agreed I do not know/remember.

NFPA54 5.6.2.3 Copper and Brass- Copper and brass pipe shall not be used if the gas contains more than an average of 0.3 grains of hydrogen sulfide per 100scf of gas (0.7mg/100l)

Find out from local Gas Company if this applies. If not why call it out?

Originally Posted by David Banks

NFPA54 5.6.2.3 Copper and Brass- Copper and brass pipe shall not be used if the gas contains more than an average of 0.3 grains of hydrogen sulfide per 100scf of gas (0.7mg/100l)

Find out from local Gas Company if this applies. If not why call it out?

Can you guarantee this to your client. I can't. Or hope that the gas supplier can guarantee that. Thats why I write it up. I will also have to open the book again but I believe it is certain copper type pipe.

Its just a safety thing I guess I am concerned with. Like I said it is always changed out. Even a short length.

A bath fans rating is done without any pipe attached. After installation the efficiency drops when using regular metal or flex pipe, adding elbows, having untaped joints, or improper flapper vent selection.
Measuring the air flow is done partway along the pipe with an inserted wand to check for pressure or flow. Using an anemometer at the bath vent location gives you an artificially high reading. If you have poor fan performance in more than one location consider a remote fan as a replacement that can handle 3 rooms. It can be installed in the attic.
Most higher cfm fans need 6 inch duct
Use a timer dial rather than a wall switch and you will find the performance way better and the fan quieter.One fan does more than the work of 3 fans for less than the cost of 3

Some may argue that a bath fan is noisy by design where you disappear for prolonged periods of time with a magazine. Have one of your favorite John Phillips De Souza cd's at the ready instead for just such an emergency.

get the builder on the list so maybe you can help the next guy.
You got a track house for custom cost. Look at this group
HADD - Homeowners Against Deficient Dwellings



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North Carolina regulates residential contractors at the STATE LEVEL.
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Chapter Representative
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please contact us.

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Rather than start a new thread:

------------------------

UBC Sec. 1203.3. In lieu of required exterior openings for natural ventilation in bathrooms containing a bathtub or shower or combination thereof, laundry rooms, and similar rooms, a mechanical ventilation system connected directly to the outside capable of providing five air changes per hour shall be provided. Such systems shall be directly connected to the outside, and the point of discharge shall be at least 3 feet (914 mm) from any opening which allows air entry into occupied portions of the building. Bathrooms which contain only a water closet or lavatory or combination thereof, and similar rooms may be ventilated with an approved mechanical recirculating fan or similar device designed to remove odors from the air.

Is there a similar provision in the IRC?

Originally Posted by Michael Thomas

Is there a similar provision in the IRC?

R303.3 Bathrooms. Bathrooms, water closet compartments and other similar rooms shall be provided with aggregate glazing area in windows of not less than 3 square feet (0.3 m2), one-half of which must be openable.
- Exception: The glazed areas shall not be required where artificial light and a mechanical ventilation system are provided. The minimum ventilation rates shall be 50 cubic feet per minute (24 L/s) for intermittent ventilation or 20 cubic feet per minute (10 L/s) for continuous ventilation. Ventilation air from the space shall be exhausted directly to the outside.

R303.4 Opening location. Outdoor intake and exhaust openings shall be located in accordance with Sections R303.4.1 and R303.4.2.
- R303.4.1 Intake openings. Mechanical and gravity outdoor air intake openings shall be located a minimum of 10 feet (3048 mm) from any hazardous or noxious contaminant, such as vents, chimneys, plumbing vents, streets, alleys, parking lots and loading docks, except as otherwise specified in this code. Where a source of contaminant is located within 10 feet (3048 mm) of an intake opening, such opening shall be located a minimum of 2 feet (610 mm) below the contaminant source.
- - For the purpose of this section, the exhaust from dwelling unit toilet rooms, bathrooms and kitchens shall not be considered as hazardous or noxious.
- R303.4.2 Exhaust openings. Outside exhaust openings shall be located so as not to create a nuisance. Exhaust air shall not be directed onto walkways.

SECTION M1501
- GENERAL
- - M1501.1 Outdoor discharge. The air removed by every mechanical exhaust system shall be discharged to the outdoors. Air shall not be exhausted into an attic, soffit, ridge vent or crawl space.
- - - Exception: Whole-house ventilation-type attic fans that discharge into the attic space of dwelling units having private attics shall be permitted.

M1506.2 Recirculation of air. Exhaust air from bathrooms and toilet rooms shall not be recirculated within a residence or to another dwelling unit and shall be exhausted directly to the outdoors. Exhaust air from bathrooms and toilet rooms shall not discharge into an attic, crawl space or other areas inside the building.

M1507.3 Ventilation rate. Ventilation systems shall be designed to have the capacity to exhaust the minimum air flow rate determined in accordance with Table M1507.3.
- Table M1507.3 states:
- - Bathrooms—Toilet Rooms / Mechanical exhaust capacity of 50 cfm intermittent or 20 cfm continuous

"For the purpose of this section, the exhaust from dwelling unit toilet rooms, bathrooms and kitchens shall not be considered as hazardous or noxious."


Guess the folks who came up with this part of code have never walked passed a bathroom after my teenager or Father have added to the sewage system.