In Residential work is the Bathroom Fan vented directly to the outside or just into the attic?

I've seen a lot that just vent into the attic. Upon exploring our New NY Residential code (based on 2000 IRC) it seems that they must be vented directly to the outside. (R303.3 Exception) Is this a new requirement?

Bill

How many times have I been in an attic (too many times) to see the vent sitting there, or no vent at all, just the fan. As far as I am aware, the venting was always to vent outside the building.

Bill
It is good to see you have a copy of the NYSRBC (and refer to it), do you have any other of the NYS code volumes?

Pierre

[This message has been edited by PCBelarge (edited 01-04-2004).]

Hi Bill and Pierre, in the south in the 70's and 80's it was common to just vent into the attic. I don't know if it was just an ignored code or not. Sometime in the 80's it was changed or atleast enforced to vent all the way to the exterior.

Roger

Pierre,

Many times I've seen the vent hose pointed towards a vent in the attic, but not actually breaking through to the outside. I was actually surprised to see the requirement there.

IMO; in NY the existence of Building codes is still a new idea to most in the Electrical field. Until the recent adoption of the International Codes I had never seen a NY Building Code and still have no idea where the old ones were sold.

We sell the codes in our 'Store' here so I have access to all of them, but I have a copy of the Residential at my desk that I've tried to look into from time to time. I also have a copy of the New 2003 International Existing Building Code that I'd like to delve into when I get a chance just to see what might be coming.

Do you know if the numbering system in the NY codes follow the International codes? I keep forgetting to get the books side by side to compare them.

Bill

The venting must go to the outside.

The problem I often encounter is people purchasing the "ventless" type of exhaust fan, which are not permitted.

Roger,

Sorry, I didn't see you sneak in there.

Thanks for the response. I actually was looking to see if any language about switching the Bath Fan was included and was surprised to find the venting requirement.

Bill

Ryan,

What type of Fan are you talking about?
Do you mean for Range Hoods?

Bill

Hi Bill, no need for an appology. I didn't have much to offer, but will investigate local codes tomorrow.

What did you find about switching?

Roger

Roger,

I didn't see anything about switching of the Bathroom Fan, only that one is necessary.

BTW, it seems like I'm studying a new language here when I look in these codes.

Glazing areas in Windows?


Bill

Bill, that must be in the Bill Gates section.

Roger

Hi Bill. I was refering to bathroom exhaust fans. They sell many that are "ductless" with a charcoal filter. They are not permitted because exhaust is required to go to the exterior, as discussed earlier.

As far as the glazing goes, if you have 1.5 square feet of openable glazing in the bathroom you need not provide a fan, but if you do, it must duct to the exterior.

If you want some real fun reading with glazing, read the "hazardous glazing locations" section in the IRC/IBC, and try to make sense of it...see ya in a few years! Lots of controversy in that section.

Seems that I have always seen EFs vented to exterior.
On the Residential stuff I did, the EFs were definitely vented to exterior.
In Commercial, the only reason an EF is not ducted, or vented to exterior is because someone fell across the duct, resulting in a nullification of the once-continuous vent path.
Secondary results are usually "Ceilings With A View" (leg holes thru drywall), and lots of pain to the duct-removing / viewport-creating person(s).

As to Glazing;

Want to see some high level "Red Tape" in regards to Glazing? Check out the California Energy Commission's Building Standards Manual for Residential and Non-Residential Occupancies.
Great reading for the Anal Retentive readers
Actually, the Glazing Specs. in the Manual (known to be Title 24, Part 6 - Chapter 2: Building Envelope), are very interresting. Many formulas are listed for use to achieve the target goals needed for compliance.

Along the lines of high functioning / Marathon Mission reading, the entire T24 Part 6 Compliance Manual is great for those like me with no life, and so is the typical Project Specification Manual!

Never seen one of the "Ductless" EFs that Ryan is referring to - maybe because I haven't contiplated their existence.?.?.? Have to do a Dedicated Browsing Trip to the local Orange Box to see one of these Animals upclose!

Scott35

Scott: I wonder if the California regulations you refer to are at all similiar to the International Energy Efficiency Code. That is, the building as a whole must comply with a certain value, which can be achieved even with cheap windows if the insulation (or other factors) are done well. There is free software available that you might find interesting to determine compliance. One is called "MECcheck" and could be easily found with a search. Also try searching "ASHRAE" for another software. Sorry I don't have the URL's on hand.

When you go to Depot or Lowe's, I'm sure you'll see the fans I speak of. Take care.

Oops, almost forgot:

Roger;


LOL!!!

Glazing ver.3.1.020.330050a For Windows 9x / M.E. / N.T. / 2000 / XP
(Windows 3.0 / 3.1 / 3.11 not supported, due to 32 bit limitations - these versions may be referred to as "Single Pane Windows").

Microsoft strongly suggests the user installs the most current version of Direct-X in the Walls, prior to installation of Glazing for Windows, ver 3.1...
Direct-X 5.0 is oldest known version to be beta tested successfully with this version of Glazing for Windows, ver 3.1...

Macros may incorporated, and interfaced to other Walls via Active-X.

Prior to installation of Glazing for Windows, ver 3.1..., verify ample free space is available on the target drive Wall for the installation routines.

Before performing installation of Glazing for Windows, ver. 3.1..., remove any existing versions of Glazing for Windows, from the target drive Wall, using the application's uninstall routine.
Restart your Car, then proceed to install the newer version - Glazing for Windows, ver 3.1...
Do not install this newer version of Glazing for Windows, ver 3.1. over any existing versions, as this will result in instable conditions.

This would be the "Quick and Dirty" description from MS.
If anyone read the older MS text manuals (like "Introduction to Windows 3.1 for example), the above stuff will make you laugh!

Scott35

Bill
The numbering is the same.

Talk about vocabulary:
How about Fenestration?

Pierre


[This message has been edited by PCBelarge (edited 01-04-2004).]

Ryan;

Check this link out, and let me know if the standards are similar:

Nonresidential Manual - 2001 Standards

The California Energy Commission Title 24 homepage can be used to do further searches.

Mentioned in the Standards Manuals, these implements have been taken into consideration by the remaining 49 States, as basis for constructing similar efficiency standards if and when a given State plans to move in this direction of Energy Conservation.
With that being said, the standards might very well mirror those in the IEEC.

For the compliance forms and project designs I deal with (Subchapter 4 - Lighting Systems and Equipment), all is done within AutoCAD with custom made templates and database listing OLE, so no helper application is needed.
Compliance forms are .DWG templates, which get attached to planset as an XREF. Stand-Alone 8½" x 11" hard copies are printed from the separate .DWG file, which get included with Planset when delivered to Building Department's Plancheck ("loose sheets" for filing).

As to the ACMs (Alternate Calculation Methods);

I have heard of "MECcheck" before, and may have seen it referenced on some plansets.
Some Approved Computer Modeling Applications are:
EZ Frame for Modeling of Framed Assemblies,
Visionsoft for MEP design compliance

ASHRAE Fundamentals Handbook is used as design standards in the Appendix for both the Residential and Non-Residential manuals.
Illuminance Categories are taken from the Office Lighting American National Standard Practice ANSI/IES RP-1, 1993.

Gotta quit typing and watch TV! I have a bad case of rubberneck between TV and Monitor - resulting in this message (and many others tonight) taking 3 times longer to post!

Scott35

Ryan,

I haven't see those Fans yet. I'll have to take a look around.

Pierre,

Fenestration? Now that's a word!
Haven't come across that one yet.

....I won't go looking for it just yet either.

Bill

Is that a window of opportunity?

[This message has been edited by Hutch (edited 01-04-2004).]

The fenestration value of a window is a measurement of how much heat/cold can come through a window, in a nutshell. Typical values are between .50 (bad) through .25 (good).

When I do a 4-way inspection, one of the things I look for is this value on the windows. If the MECcheck shows compliance with the IECC by using a .35 U-value and .50 windows are installed, the GC can re-submit the MECcheck showing the lesser windows, or they can remove and replace them. A normal fix would be to increase the insulation in the roof from an R-38 to something higher until the MECcheck shows compliance.

BTW: You New Yorker's are something else, staying up until midnight, talking aobut fenestration values and glazing!!!

[This message has been edited by Ryan_J (edited 01-04-2004).]

Ryan,

This is EXCITING STUFF!!


Bill

Guy's,
It's been a requirement of the Building Code here, for the last 10 years, to vent all steam(from showers, dryers and cooking appliances) to the outside atmosphere, usually through in-line fans and ducting (circular).
One duct for each, normally taken either through the soffits, or (ugh ), the roofing iron.

Builder I sub elec. from asked me to leave enough hose to reach up to roof (opposed to soffit, the usual) in one house because the $$ was FHA or FANNIE MAY , or something like that; in another house I ran 3'' from 1st fl. powder rm. out over/into soffited porch, which 3rd. party insp. passed but I'm waiting to see what township insp. has to say.Can't imagine any real moisture fr. powder rm.,but again we'll see.

One County in this area won't even allow flexible duct for bath fans (which must be vented outside).
Their contention is that the convolutions create a "trap" which will catch and keep moisture and bacteria.

Scott35,
I once printed the entire '95 Title 24 Non-resi. All 600 and some odd pages.
I to this day have not had time to read it, only the 80 or so electrical pages. (and that's 2 Code cycles old) ...S

The U.K. building regs. have a clause relating to a bathroom needing an openable window, the area of which I believe is either some minimum size or related proportionally to the volume of the room. If such a window is not feasible, or the bathroom has no window at all, then mechanical venting is required.

I've seen bathroom fans vented into the attic here, but I don't much care for the idea. Who wants all that water vapor deposited up there?

Range hoods are a mixed bag here: Some are vented outside, others are fitted with a charcoal filter and just recycle the air back into the room. Many of the latest models come with two sets of adapters and fittings to allow either installation method.

...Who wants all that water vapor deposited up there?

Yup. Here in New York, most times I've seen this it resulted in the roof sheathing rotting out. The moisture condenses on the underside during our cold winters. A couple of times there was not much more left than the shingles!

This thread is "off topic".

The moderator has been informed and it will be moved to "HVAC Contractor Network" forthwit!

LOL


Coastal,

I see you're from Kill Devil Hills. I vacation down near the Village Beach Club in Nags Head, just a Brew Thru away!


Bill

Small world, Bill!

Maybe we can get together, time permitting for the both of us, the next time you are in the area!

Yes, the world is getting smaller every day!

I may go down again this Summer, I don't know yet. We've been down there a number of times over the last 10 years. I notice changes everytime we go down. A lot of new Building. I remember when the Dunes at Jockey Ridge were twice as high!


Bill

Around these parts, a half-bath with a window may not need a fan, but all others do; the presence of a tub or shower requires the fan, window or not.

As mentioned above, the fan must be ducted to the outside due to moisture. "Fenestration" probably stems from the French "la fenetre", the window.

Larry, you are absolutely correct....next, you'll be telling us that these are also called "fard fans", from the French "Fard", which means 'to apply make-up."

I'm thinking the requirment for my state is the fan must be switched with the light. Something about not switched seperatly because of the noise involved, it would not get used. I have found many just vented into the attic.

I prefer separate switches so the fan can/wll be used without, or leaving on after, turning off the light.

Many bathroom fans here use a built-in timer so they turn on with the light and switch off a few minutes after the light goes off. The time delay is usually adjustable from a couple of seconds to sevreal minutes.

Personally, I prefer the fan to be on its own independent switch.

Paul, you can also buy a single switch with two load wires that does the same thing: light off immediately, fan off after 10 minutes (or adjustable, I don't remember).

If it was my house, I would never vent to the attic..........

Good Day!

Here in Maple Ridge, the bath fan must be vented to the out side, and the 14/2 must be run directly from the main bath fan directly to a relay in the furnace with a time clock on it so that when the furnace motor comes on (LOW) for the CFM required air exchanged, the bath fan must also come on with it, and is to be connected to the time clock as so that the fan is over ridden by the blower (LOW) motor on an 8 Hrs on, 8 Hrs off cycle for the fan, and wired so that it can not be over ridden any other way, so you have no choice but to install a relay before the time clock to isolate the furnace motor, (LOW) and the bath fan, so the motor can’t back feed the fan and blow the PCB in the furnace it self.
We have argued up and down that this should not be done by us, but the furnace installation company, and that by our cutting into the low speed motor circuit and adding that iso relay, that it is now considered not to be SA approved any longer and warranty issues, as the circuit board has now been altered, oras per the “ALTERATION of EQUIPMENT” rule.

The inspector here also looks for an extra wire run in the attic and left by the 1 gang box, so when the final has passed, the home owner wishes for us to remove the 1 Gang or 2001, and replace it with a 2002, 2 Gang and put the over ride switch in it like it used to be in the 90’s (WHICH I WILL NOT DO PERIOD), forif you are caught, you’re license is suspended, but I feel for the home owner as that fan will drive you crazy if it is near the master bed room(AS WHEN ALMOST IS IT NOT?) and is cycling at 2:30 in the morning even, the low sone fans, but them’s the rules here in Maple Ridge, and Coquitlam areas.
I do not know if that part of the building code is enforced anywhere else, but if anyone knows, I wish they could post it, as I would greatly appreciate it just to keep up with things!

Have a good day!

Robert Wagner!

To summarize the vent codes:

IRC 2003 R303.3 Exception requires ventilation air from bathrooms be exhausted directly to the outside.
IRC 2003 M1501 requires clothes dryers to exhaust outside the building.
IRC 2003 M1502 prohibits range hoods from terminating in the attic.
- none of these have changed from IRC 2000, though the cfm requirements section is annotated as having changed. (Intermittant 100cfm for kitchens and 50cfm for baths in 2003)

Watch the UL listing on the bathroom fan duct, too- "air connectors" (as usually used for bathroom fans) are limited to 14', while "air duct" can be unlimited length.

[This message has been edited by SteveFehr (edited 10-22-2006).]

When we bought out house, the inspector noticed mold in the attic on the underside of the roof sheathing. Luckily it wasn't one of the nastier strains, but we wound up having the roof replaced (needed new shingles anyway) as part of a non remediation "remediation".

The HI thought it was due to the soffit vents being covered by blown in insulation and the venting of the bathroom fan directly into the attic space.

In northern minnesota if you vent into the attic it will turn to frost in your attic and when it gets warm your cieling and insulation is going to get wet and could mold and just cause problems that a vent to the outside would prevent.

In NJ, Building codes require you vent thru the roof

I hate fans vented to the attic. I never have and never will. We were on a remodel about 10 years ago. The bath fan was vented directly to the attic near the furnace. My wireman had onion rings for lunch and the HVAC guys were changing the furnace. Good time to work in the basement.

Fans should be vented to the outside! Was asked by a customer to look at a bath fan (Broan located near the shower)that was making an odd sound, sort of a whup, whup, whup. Okay, I figured something's loose somewhere. Up to the attic and discover about 20' of 4" flexible plastic duct with a goose neck in it. Upon closer inspection, I noticed that the goose neck was full of water (1.5 - 2 Gals.). The fan would build up enough pressure and be able to push past the weight of the water. Pressure drops and the struggle begins again. Drained the goose neck and re-ran the vent. I don't think installing the goose neck was intentional. It probably started out slight and grew with accumulated water.