Building Code and Building Construction - Questions and Answers
Or when you want to know how construction is supposed to be done.

|
AskCodeMan.com
|

Custom Search

dryer vent in high rise building

dryer vent in high rise building

New postby Lynn2202 on Wed Nov 04, 2009 3:00 pm

What are the code requirements for clothes dryer ventilation that runs the entire length of high rise condominium (vents to the roof). The building was built in 1995, is 26 floors high and has a vent for each "condo line". I'm specifically looking for the required size of the vent and if it must be constructed with a double wall and insullation.

Thanks for any help you can offer.
Lynn2202
 
Posts: 2
Joined: Wed Nov 04, 2009 2:28 pm

Re: dryer vent in high rise building

New postby Jerry Peck - Codeman on Wed Nov 04, 2009 8:06 pm

Lynn2202 wrote:I'm specifically looking for the required size of the vent and if it must be constructed with a double wall and insullation.


Your question has a complex answer, so I will start here:
- The vent size within the condo will be the standard 4 inch size (unless the designers of the system increased the size for whatever reasons they had).
- The vent size for the main riser is dependent on the engineering done regarding the number of inlets on each riser, the connection to each riser, the size (CFM rating) of the roof mounted exhaust fans, and other considerations,
- The riser would have been required to have been constructed and sealed at all joints, then enclosed in at least a 2 hour rated shaft enclosure.
- The dryer duct within each condo is not allowed to be in the plenum, thus each condo dryer duct should have been sealed off from the plenum, typically by enclosing in metal framing chase/soffit which is then covered with gypsum board which is bedded and taped to seal the dryer duct off from the plenum.
- The dryer duct within each condo would have either been 26 gage or 30 gage sheet metal.

Those are the basics for that riser and the condo branch duct to each dryer connection.

Hopefully in there somewhere I answered your questions.
Jerry Peck - CodeMan
AskCodeMan.com
Construction Litigation Consultant - Retired
Construction and Code Consultant - Semi Retired
User avatar
Jerry Peck - Codeman
Site Admin
 
Posts: 1199
Joined: Fri Dec 12, 2008 12:06 pm

Re: dryer vent in high rise building

New postby Lynn2202 on Wed Nov 04, 2009 9:50 pm

Thanks so much for your help. We had a unit owner alter the size of the soffit without pulling a permit. when we questioned the owners they said they would "put it back like it was" but I think we need to require that the work be inspected to ensure that it is done correctly - even if it means that they (or their GC will have to pay a fine).
Lynn2202
 
Posts: 2
Joined: Wed Nov 04, 2009 2:28 pm

Re: dryer vent in high rise building

New postby Jerry Peck - Codeman on Wed Nov 04, 2009 10:07 pm

Lynn2202 wrote:but I think we need to require that the work be inspected to ensure that it is done correctly


Absolutely require that they obtain a permit, obtain the drawings from the building department (if still available), and those drawings will show the requirements for that soffit/chase and its fire-resistance rating (if it was fire-resistance rated) and THAT is how it needs to be reconstructed.

Depending on what part they altered, it may or may not have been part of the fire-resistance rated assembly, and if it was the reconstruction needs to be done in accordance with the requirements for the fire-resistance rating ... the CURRENT requirements, not the old requirements, as the word is "new work".

Being as this is in a condo building, the need to have that done correctly is a very important legal need for the interests and protection of ALL the residents in the condo building. One of the reasons doing work without permits is not a good thing.
Jerry Peck - CodeMan
AskCodeMan.com
Construction Litigation Consultant - Retired
Construction and Code Consultant - Semi Retired
User avatar
Jerry Peck - Codeman
Site Admin
 
Posts: 1199
Joined: Fri Dec 12, 2008 12:06 pm


Return to Mechanical: Heating and cooling equipment, duct work, ventilation and exhaust fans



Who is online

Users browsing this forum: No registered users and 1 guest