I have a fair amount of noise in my bathroom from the
bathroom of an adjacent apt. It mostly comes through
the ventilation duct, which is about 6" in diameter.

Can I put some sort of baffle into this duct to cut the
sound transmission?
If that reduces air flow, should I put a fan on the
outside of the thing, to boost air flow?

Oh, and I should mention... Not only do I have access
to the "end" of the duct, but I can get into a crawl
space in my bathroom where I can access several
feet of the duct work before it terminates on my ceiling


Thanks.

"Charles Robertson, Psy.D." wrote:

Change the duct to flex duct with several 135 degree bends in it. Sound
doesn't turn corners very well.
chuck

You will have to increase the diameter to still get the same air flow.
Moving air doesn't turn corners very well either.

--Dale

"Charles Robertson, Psy.D." wrote in
:

Change the duct to flex duct with several 135 degree bends in it. Sound
doesn't turn corners very well.
chuck

Good idea. Also you put insulation board (703) inside the duct! You can
also make a slotted peice of fiberboard inside 6" or so from the grate.

Best,

Mack

Good idea. Also you put insulation board (703) inside the duct! You can
also make a slotted peice of fiberboard inside 6" or so from the grate.

Insulation board INSIDE? How does air flow?

As for the slotted fiberboard, what size slots?

www.ttdown.com wrote in
:

Good idea. Also you put insulation board (703) inside the duct! You can
also make a slotted peice of fiberboard inside 6" or so from the grate.

Insulation board INSIDE? How does air flow?

As for the slotted fiberboard, what size slots?




http://arts.ucsc.edu/ems/music/tech_.../teces_14.html

Good idea. Also you put insulation board (703) inside the duct! You can
also make a slotted peice of fiberboard inside 6" or so from the grate.

You can buy insulated duct and duct silencers. Restricting the airflow with a
slotted piece of fiberboard will likely generate turbulence and make more noise
than you had in the first place. Generally large ducts with a lot of turns and
several duct silencers satisfactorily reduces noise transmission down the duct
without adding wind noise. Talk to an HVAC person. The right materials are
cheaper to buy than to build, and installing them once is way cheaper than
redoing it unil you get satisfactory results.


Joe Egan
EMP
Colchester, VT
www.eganmedia.com