Anyone ever soundproofed a door?

[sjalloq]

Hi,

I've got a small cupboard in a bedroom that I've put my networking gear in so think of a loud computer fan spinning away. I'm going to tread the cupboard walls with foam or other dampening materials but I'm not sure what to do with the door.

As it currently stands there are no door stops in the frame, as I've just had the room painted, so I was planning on fitting chunky stops all round which would allow for rubber seals or some other soundproofing strip. Regarding the door itself, any thoughts on whether fitting some sort of panel to the back of a standard door would work or whether it's worth me building one with a specific interior structure?

Thanks.

 

[MusicMan]

For soundproofing a door think (a) stopping all gaps, you have that one down, (b) weight and (c) high damping material. So thin wood is awful, solid wood is poor as it has little damping. Synthetic materials good, laminated or granular materials good (plywood or MDF). A fire door is probably the easiest way to get all this.

Foam lining will do a little, if you use heavy acoustic foam. Ordinary foam rubber won't do much at all.

 

[MikeG.]

It's about weight, gap-sealing, and diffusion/absorption. There are squillions of products to do the latter, but I've been inside a few professionally soundproofed rooms (Radio studios, and a hearing clinic) and they all had a coarse carpet on the door. The doors were 4 inches thick plus. So0 a big heavy solid door with a lining on the inside, beautifully sealed all around.......

.............is that going to suit the equipment inside? It could get incredibly warm in there.

 

[thetyreman]

prevent it at the source instead, get a new quieter fan ideally where you can lower or control the speed

 

[Robbo3]

Computer suppliers sell both sound deadening & sound absorbing materials.
Are you sure putting the equipment in an airtight cupboard is the right thing to do?
The equipment generates heat. If there is a limited supply of air the temperature will rise until there is little or no cooling effect. That may be a higher temperature than the equipment can stand.

 

[thetyreman]

air will have to flow through it or the computer will overheat and fail, you need a way for the air to get in and out.

 

[Jacob]

Yes to fire door etc. above.
I had to demolish sound proof doors in our chapel. They looked like normal 19C pine panel doors but the panels were doubled up with the gap filled with sawdust. They were also lined on outside with thick purple felt.
The felt idea would help perhaps, or curtains etc.

 

[thetyreman]

From what I've seen in high end pro studios soundproofed doors are VERY heavy and very expensive affairs, I know that the BBC used to line them with lead and fill them with heavy density builders sand. You need specialist hinges the ones that lift when opened and designed to take 100+ KG, and special door thresholds that seal it airtight as it closes, these are not cheap, the only company I know of that make them are customaudiodesigns.co.uk based in oxford, but it might be overkill for just a door on a PC cabinet lol better to just replace the fan for about a tenner, try and aim for self noise of around 10dB or less if you can find it, noctua make excellent fans that are controllable, they come with adapters so that you can lower the speed and therefore noise and are more efficient longterm than a cheap/stock PC fan, seriously consider it before trying to soundproof anything, it might be cheaper.

 

[sjalloq]

Thanks for all the advice regarding the door. I'll have to do some more research.

No worries on cooling, got that sorted. I also can't replace the fans with quiet ones as this is 19" rack equipment with high static pressure fans. I've got a UPS, two servers, two switches and various routers etc. That's why I'm looking at the door.

 

[Beau]

I think you will get the best results for minimum outlay by sealing the gaps and lining with sound absorption materials. This should work well http://www.rockwool.co.uk/products/rock ... tion-slab/

 

[Raymond UK]

I've got a 17U 19" rack with several servers, switches etc and moved it up into the attic. It's just whirring away up there and can't be heard.

 

[Adam9453]

You can achieve pretty decent acoustic insulation with even a 44mm fire door blank. As mentioned above, the crucial bit is sealing the gaps around the door. Firstly the batwing seal should be fitted into where the door presses against the door stop at the Jambs and head of the door (see Lorient LAS1212), then ideally fit a fir tree acoustic seal (see Lorient LAS1011) into the edge of the door (again at Jambs and head) towards the hinge knuckle face of the door to create an air gap between the fir tree seal and the batwing seal. Lastly fit a drop seal into the bottom of the door that automatically seals shut when the door is closed (see Lorient LAS8001). This should achieve circa 32-35db rating depending upon the blank used to make the door leaf. For even higher acoustic ratings you could use a moralt firesound blank but they are awfully expensive (ie hundreds for just the blank). The thicker the door, then typically the higher the acoustic rating achieveable. Also it’s not commonly known but adding glass to a door (ie a vision panel) typically improves the acoustic rating of the door (providing it’s fitted using the correct glazing system or gasket). If the door needs to be fire rated then the fir tree seal can be replaced or complimented by an intumescent seals with fins or brush. Hope that helps

 

[thetyreman]

Also it’s not commonly known but adding glass to a door (ie a vision panel) typically improves the acoustic rating of the door (providing it’s fitted using the correct glazing system or gasket). If the door needs to be fire rated then the fir tree seal can be replaced or complimented by an intumescent seals with fins or brush. Hope that helps

actually the exact opposite is true, any kind of hole or glass panelling reduces performance, even with seals, it's a compromise vs the door without the glass panel, do you have any scientific evidence with data to prove this claim?

 

[Adam9453]

Funny how attacking your post is to someone trying to offer help to someone else.
Yes there is test data to support it.
You’d think the opposite is true but the data says otherwise. Try googling it and you’ll find out for yourself

 

[MikeG.]

I have no idea who is right or wrong about the panel, but as it is your claim, Adam, the onus is on you to back it up. If you have a link to some test data that would be really useful, thanks.

 

[Adam9453]

Look up acousticselector.com website, it provides all the information

 

[thetyreman]

here's what I got from the link you provided

 

[thetyreman]

the way they measure it is also flawed, dBRw... I haven't seen this measurement before, so do not know what Rw stands for, I have an understanding of Decibels, but usually in acoustics they use STC Sound Transmission Class or SRI Sound Reduction Index as the proper way to measure isolation.

info here

STC https://en.wikipedia.org/wiki/Sound_transmission_class
SRI https://en.wikipedia.org/wiki/Sound_reduction_index

 

[AJB Temple]

It is possible to get glass that will block around 95% of sound. It's expensive, is less effective on low frequency sound, and is used in a different way to materials designed to absorb rather than reflect.

I used to own a recording studio about 10 years ago, and for design reasons we needed one wall fully glazed and capable of being opened up. It had a big Fazioli piano in it. We also had acoustic shields for when we wished to deal with sound reflection from the glass.

We have a similar problem in my office at home. I have a leased line for uncontended high speed internet and this uses a double fan termination unit which sounds like a jet turbine inside the house. Very annoying. The solution was a soundproof (almost) computer rack cabinet, with venting to the outside air.

 

[Adam9453]

Ok, take a look at the following link;
http://sealedtightsolutions.com/wp-cont ... REAK44.pdf

Or look at the Lorient acoustic selector as there are further examples of glazed doors with a higher acoustic rating than the non glazed doors.

Frankly I’m not going to debate this as whether you agree or disagree is irrelevant. The intention of my post was to help the OP which I hope it has done.