Single family residential laundry rooms

[Arp32]

I've included a switched ceiling mounted ventilation fan in laundry rooms for as long as I can remember. When I first started designing homes, plan reviewers redlined me for this requirement and I never questioned it.

A contractor has recently pushed back at me on this, saying that the 4" exhaust duct from the back of the clothes dryer *is* the required exhaust ventilation for the laundry room, and a separate ceiling mounted fan & duct is not required.

Reading M1502. I don't see it calling for a separate fan and duct. Is that a requirement coming from somewhere else in the code, or have I just been calling out extraneous fans for years?


-Jason, Architect

 

[EnergyProfessional]

You have to bring that up to whoever red-lined it.
Could be a lot of things JHA didn't like... local codes, flowrate, control etc.

 

[IRstuff]

What was the intent of the second fan? How big are these laundry rooms?

While comfort might be affected, people don't always spend extended times in laundry rooms while the dryer is running, and if the room is larger than about 50 sqft, the heat load from the dryer isn't necessarily that bad. I've had 3 different configurations, laundry closet, 100-ish sqft and 50-ish sqft; only the latter was uncomfortable, but it's so small there's not much one can be doing in it for any extended time.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529 Entire Forum list

http://www.eng-tips.com/forumlist.cfm

 

[Arp32]

These are just normal everyday laundry rooms, 6' x 8', maybe 8' x 12'. Nothing special.

It's been so long I don't recall the specific house when the AHJ comment came up, just that I was told a vent fan was required for code compliance and I never questioned it until this week. I noticed there was no fan at the existing laundry room on a very small remodel and the location of the laundry would have made adding ductwork kind of a huge deal relative to the limited scope of the project.

Either it was a local amendment or a bogus comment I should have pushed back on. I'm not finding anything in the IRC or IMC...



-Jason, Architect

 

[IRstuff]

4 houses lived in, only 2 with actual laundry rooms; neither had fans, but I can imagine if it was someplace really hot or humid, a ceiling fan might help things out.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529 Entire Forum list

http://www.eng-tips.com/forumlist.cfm

 

[GT-EGR]

You only need the second fan if you exceed the allowable amount of straight length and fittings allowed by the dryer manufacturer. The dryer has a fan with some pressure behind it to get the exhaust air out. But if you have a long way to go to get outside or a lot of twists and turns, the airflow will get restricted and the dry cycles will take longer.

I’d say you want to avoid putting in a second fan, just more things to restrict and fail and maintain and if you don’t filter it well it’s another area that lint will build up. You also need to do it correctly since you are putting two fans in series.

 

[AdrienneGC]

I agree with everyone else, I have not seen any code requirements for additional exhaust in the laundry room and don't include it any of my designs.

Adrienne Gould-Choquette, P.E.

http://www.adicot.com