Extractor Fan Noise - Vibration

If your fan is fitted into the ceiling itself then there's not a lot you can do about it, the fans motor is whirring away above your head and you need a dense barrier or plenty of airspace between that and your ears for you not to hear it.


Here's a solution for inline fans.

Make a 'box within a box'... same principle of soundproofing studios (room within a room)

Basically make an mdf box (with lid) around the fan, drill holes for the ducting at either end, line it with rockwool. Make another bigger box to house the 1st box, drill holes for the ducting at either end, also line that with rockwool, and place the 1st box inside the 2nd, so that all 6 sides are in contact with the rockwool. Stick the box anywhere you like, the insulation will dampen any vibes.

You can hard fix the fan inside the first box using builders band.

It doesn't matter if you can't get hold of rockwool, use normal fluffy insulation, just don't pack it in too tightly.


If you want to also silence the noise of the fan motor itself, then attach the ducting to the outer box only, and carve a hole through the insulation so that the airflow passes freely between the 2 boxes. The bigger this gap, the quieter it will be.

Be sure to make the inner box big enough to fit the fan inside, with an airspace between it and all the insulation. Also use 18mm MDF, and mount the whole lot as far away from your bathroom vent as possible.
 
Sponsored Links
Thanks for the idea. I'll have a look and see if my limited DIY skills are up to it. Sounds ok.
Can I assume the rafters won't vibrate?
Cheers,

Pete
 
peteuk said:
Thanks for the idea. I'll have a look and see if my limited DIY skills are up to it. Sounds ok.
Can I assume the rafters won't vibrate?
Cheers,

Pete

Well I can't guarantee that 100%, but if you think about it, the inner box will be in contact with nothing but insulation, which will absorb and dampen quite a bit. The more insulation the better (which also means a bigger box)

It's also important to make sure the whole thing is firmly secured to a joist or wall.
 
Sponsored Links
peteuk said:
Thanks for the idea. I'll have a look and see if my limited DIY skills are up to it. Sounds ok.
Can I assume the rafters won't vibrate?
Cheers,

Pete

You will not have the ceiling acting as a sounding board by using the rafters.
You will have the opportunity to try some padding at the interfaces, plinth hanger to rafter and plinth, plinth to fan unit.

A little like this perhaps.
Hang.jpg

;)
 

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Back
Top