[Lamantino]

I am planning on soundproofing space in my house and want to buy and install soundproof interior door as part of this project.
Looks like I will need to get a 32" x 80" door and shave it a bit to match my existing door jam so it will need to be a wood door.

Looking online I am confused if it's better to go with a solid wood door or a solid core door. Do door manufactures provide STC ratings for doors?
Where/How can I find a reasonable priced door with relatively high STC rating?

My concern is that I end up having a high STC rating (e.g. 50) everywhere in the wall, but the door will be the "weakest link" (e.g. with STC rating of 30-35) causing sound to escape through it.

Any help is appreciated!

 

[Chris616]

My concern is that I end up having a high STC rating (e.g. 50) ever where in the wall, but the door will be the "weakest link" (e.g. with STC rating of 30-35) causing sound to escape through it.

You're correct that the sound heard will depend on the "weakest link", so something to consider for every interior door is the air gap at the bottom. When we renovated our house and put the mechanical room with its sound generating equipment adjacent to and with a door into the room where we sit most evenings we installed an insulated exterior door with a sealing door threshold.

 

[SW Dweller]

As long as you go with a solid door you will accomplish all that you can do. Fit in the door way is important as well as possibly the weather striping you use for the door.
Weather striping is the last bit to help. Just like you use for your exterior doors.

 

[YaterSpoon]

Sound "reduction" is much more realistic.

 

[chandler48]

If the door opens to the inside, you could glue homasote panels on the inside to help reduce sound attenuation. But as @YaterSpoon stated, you'll only "reduce" it, not "proof" it.

 

[Half-fast eddie]

Solid core and solid wood will be essentially the same. You can get a solid core with a lead lining, that will attenuate the sound pretty well. Don’t forget to use a good weatherstriping to seal the perimeter of the door.

 

[Elmer-Dallas Texas]

You would have to be crafty to make it look good but you could glue oversized Tred-Mor to the interior (assuming it opens inward) of the door.

 

[Lamantino]

Thanks everyone! I am currently thinking of getting a 1-3/4" solid core door with no panels. Then install it with weather striping and potentially a door sweep. I can always take it one step further at later time by gluing some panels to the door to reduce the sound if it's still a concern.

 

[GCTony]

I deal with commercial doors professionally. Off the top of my head the highest stc rating for a mineral core door (AKA fire rated) was in the 40's. Fire doors with smoke seals are used a lot as "sound proof" doors. Weather striping, smoke seals and sound seals are all different things.
If you had the option of building your own door, you could install a mass load vinyl inside the door, basically a dense material designed to stop (not deflect) sound waves. If door thickness isn't an issue, how about a 1-3/8" door, add the 1/8" membrane and a 1/4" door face giving you a 1-3/4" thick door.

An over the counter door system will run you somewhere around $5,000.00

A company we work with but they have an online store
Door & Window Solutions Archives

 

[HotRodx10]

Depending on what frequencies of sound you're trying to reduce, different materials will work better than others. For voices and other higher frequency noise, you would do fairly well by sandwiching 1" rigid foam, or a couple layers of sound board, between 1/4" plywood. For low frequencies, the solid core door is probably the best you can do for the door itself, but you'll probably need to add acoustic foam to inside and outside to get any significant reduction.

Don't underestimate the effect of adding a turn or 2 to the approach to the room. Higher frequencies especially, do not go around corners very well, especially if the walls are faced with soft materials. If you're really serious about major reductions in sound levels, add an 'entryway' that turns 90 degrees, face the walls with acoustical foam, and add a second door at the end of it.