Doors for sound studio

[coolandeasy]

Planning double-stud wall construction (12 ft x 12 ft x 8 ft high)
Out-to-in it looks like this: double drywall, 2x4 studs, batt insulation, 2" space, batt insulation, 2x4 studs, double drywall
Ceiling structure still uncertain. Floor is concrete. Inside warehouse.

My best idea is to have two steel hollow commercial security doors, opening out and in.
What are your thoughts or experiences with this type of door: 36 in. x 84 in. Fire-Rated Gray Right-Hand Flush Steel Commercial Door with Knock Down Frame and Hardware
homedepot.com/p/Armor-Door-36-in-x-84-in-Fire-Rated-Gray-Right-Hand-Flush-Steel-Commercial-Door-with-Knock-Down-Frame-and-Hardware-VSDFPKD3684ER/207153510

I got this idea from this thread forums.audioholics.com/forums/threads/communicating-doors-in-a-double-wall.29536/

Moreover, discussion about specifics is appreciated (welded vs knock-down frame, frame depth). For example: new construction welded frame is recommended, but I will have to disassemble this in a few years, maybe knock-down is not bad and is better choice for transport. 6-1/8" deep frame is recommended for double-dry-wall construction, but advice for double-stud-wall construction is rare.

I've searched the forums and done a few hours of googling about doors. Yes, very easy to forget about this topic and i'd like to make sure i'm on the right track. These are expensive components with little consumer transparency, easy to overpay.

 

[mtrycrafts]

Planning double-stud wall construction (12 ft x 12 ft x 8 ft high)
Out-to-in it looks like this: double drywall, 2x4 studs, batt insulation, 2" space, batt insulation, 2x4 studs, double drywall
Ceiling structure still uncertain. Floor is concrete. Inside warehouse.

My best idea is to have two steel hollow commercial security doors, opening out and in.
What are your thoughts or experiences with this type of door: 36 in. x 84 in. Fire-Rated Gray Right-Hand Flush Steel Commercial Door with Knock Down Frame and Hardware
homedepot.com/p/Armor-Door-36-in-x-84-in-Fire-Rated-Gray-Right-Hand-Flush-Steel-Commercial-Door-with-Knock-Down-Frame-and-Hardware-VSDFPKD3684ER/207153510

I got this idea from this thread forums.audioholics.com/forums/threads/communicating-doors-in-a-double-wall.29536/

Moreover, discussion about specifics is appreciated (welded vs knock-down frame, frame depth). For example: new construction welded frame is recommended, but I will have to disassemble this in a few years, maybe knock-down is not bad and is better choice for transport. 6-1/8" deep frame is recommended for double-dry-wall construction, but advice for double-stud-wall construction is rare.

I've searched the forums and done a few hours of googling about doors. Yes, very easy to forget about this topic and i'd like to make sure i'm on the right track. These are expensive components with little consumer transparency, easy to overpay.

Welcome to AH.

I would suggest not using hollow steel doors but either solid core wood or wood paneled doors with good insulation between. Two doors of course with weather strips all 4 side on each doors. Perhaps a Google search for sound deadening doors?
One search recommends hollow core, filled with expanding foam; drill hole at top and bottom. May need more holes?

 

[Alex2507]

I've searched the forums and done a few hours of googling about doors.

Google door supplier. Never use the words Home Depot again. Ask about STC and talk about your budget. Ask about automatic door sweeps and weather stripping. Ask about wood vs metal regarding sound transmission class. A door supplier will have that info and they'll have the $100 weather stripping. 2 doors and frames? Probably ... easily $1500 for anything remotely 'nice' and more with heavy regard toward higher STC.

Stuff the welded frames with mineral wool and screw drywall to the backs of the frames making a tunnel of sorts. Slide into rough opening. Shim it to reveal perfection and glue the piss out of it ... walk away.

Alright, that was my best if the karate guy in from Napoleon Dynamite was also a carpenter.

 

[coolandeasy]

Thank you very much for interacting with my post.

After further research it appears that the best cost-effective course of action is to order two or three heavy-duty 1000-lb door hinges ($100-150) and build your own door "barndoor style" using something like 2x4 frame, 2x8 lumber backing, with two 5/8" drywall layers fastened with screws. Push-pull door configuration to avoid holes in the door.

What do you think of the above rough idea?

I know this is just the structural part; equally important is the air-tight seal around the door. Thanks to your posts i determined that filling a hollow door with sand or foam is unlikely to work because there is probably a honeycomb cardboard or vinyl filling in the steel door. Also, it would be harder to screw drywall to the steel door. As a starting base for further treatment, a hollow steel door is not a good candidate. The solid-wood doors available to me locally are not the 3 ft x 7 ft size I would like , so building your own is probably a good option.

Specialty acoustic doors are all "request quote for price" and the price is invariably $2,500 or so. That's when the materials for the entire 4-ton structure are about $1800 before discounts. I imagine it's a nice business if you're selling; i know because there are many stupid-simple niches that are very profitable for those who work them.