Soundproof door advice

I'm looking for advice in building a "soundproof" door between my basement listening room and the utility room which has the washer & dryer along with the furnace. The opening is aprox. 6' x 4.5" and currently doesn't have a door.

Because of space available I won't be able to use a hinged door it will have to be a sliding door.

I thought about screwing multiple sheets of plywood together but I'm not sure if warping will be a problem.

The top of the door will be almost flush with a HVAC duct so I can't use sliding barn door hardware to hang the door. My thought was some type furniture glider on the bottom of the door.

Any ideas??

Thanks in advance!

Scott
 
Hi Trekpilot, sound travels two ways from one room to another. Through air movement as you are discovering with an open doorway and through vibration in the structure of the building. Both of these need to be treated differently. For the door you are right in thinking it needs to be solid. Hollow doors act like a sound box in themselves with one side transferring sound to the other and re-radiating it into the room. The problem you are going to have is making it sliding and getting a sufficiently good seal to the frame. For hinged doors one solution is to inset a seal into the frame that is compressed when the door is closed. For studio doors that seal would be magnetic, just like your fridge door, with a metal strip set into the edge of the door. The bottom would also have a rubber seal pressing against the floor.

A sliding door when closed will have a significant air gap around it and depending how you mount it is likely to move with sound , if played loud and the vibration from the appliances in the utility room. Another area you should look at is above the ceilings. Thin ceiling linings do little to stop sound transmission and whilst you may be successful with the door you could find sound hopping over the top. The solution here is sound proofing batts above both rooms.

Finally there will be the the vibration from the appliances transmitted though the structure of the rooms. You may not notice this too much now but once you reduce the radiated sound it can become a problem. This is a difficult area and often not a lot you can do. The washer dryer could be stood on isolating pads and make sure it is not hard against a fixed surface. Also all connections should be rubber hoses. As for the furnace this will be fixed to the building structure and will expand as it heats then cools, as will the ducting you describe. Not the easiest of tasks Good Luck
 
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Joined 2009
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^ totally analogue: +1.
Trekpilot, it could be fine to first identify the kind of 'noise' you want to be isolated from, as it'll mainly determine your approach ( annoying frequency range).

Soundproofing (hinged) doors may be difficults to diy in reasonable space.

Sliding doors i have seen properly implemented for soundproofing where from this kind:
Baie vitree coulissante aluminium Deva - Lapeyre

In ( top notch) studios you can see them implemented between control room and studios/recording booth, one each rooms with a relatively wide (isolated : each floorplan of each room is floating so decoupled one of the others) space between them ( i've seen up to 70cm depth ).

This works because each room is decoupled from each other ( and the space between them too) and because of the space between each room ( box into box).

You can see how it is implemented in diy here:

Creation d'un studio d'enregistrement - Sonaye Blog

I seriously doubt about the efficiency of any soundproofing of the door in this link. But the implementation of box in a box is.
 
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Hi Trekpilot, sound travels two ways from one room to another. Through air movement as you are discovering with an open doorway and through vibration in the structure of the building. Both of these need to be treated differently. For the door you are right in thinking it needs to be solid. Hollow doors act like a sound box in themselves with one side transferring sound to the other and re-radiating it into the room. The problem you are going to have is making it sliding and getting a sufficiently good seal to the frame. For hinged doors one solution is to inset a seal into the frame that is compressed when the door is closed. For studio doors that seal would be magnetic, just like your fridge door, with a metal strip set into the edge of the door. The bottom would also have a rubber seal pressing against the floor.

A sliding door when closed will have a significant air gap around it and depending how you mount it is likely to move with sound , if played loud and the vibration from the appliances in the utility room. Another area you should look at is above the ceilings. Thin ceiling linings do little to stop sound transmission and whilst you may be successful with the door you could find sound hopping over the top. The solution here is sound proofing batts above both rooms.

Finally there will be the the vibration from the appliances transmitted though the structure of the rooms. You may not notice this too much now but once you reduce the radiated sound it can become a problem. This is a difficult area and often not a lot you can do. The washer dryer could be stood on isolating pads and make sure it is not hard against a fixed surface. Also all connections should be rubber hoses. As for the furnace this will be fixed to the building structure and will expand as it heats then cools, as will the ducting you describe. Not the easiest of tasks Good Luck

Thanks for your reply.
I will take a look at insulating the floor joist area above the wall that separates the two rooms along with insulating the wall itself and then enclosing it with drywall. I do have the area above my listening room insulated.

I understand the challenge of sealing a sliding door and I wish I had the room to install a hinged door.
I was thinking of some type of felt wiper or foam weather stripping between the sliding door and the fixed wall to try to establish some kind of seal.

I will also look into some sort of isolation pads for the washer and dryer.

Thanks again,
Scott
 
diyAudio Member
Joined 2007
Actually a heavy blanket can work wonders. To work best it may need to be doubled with one draped on each side and with a decent pelmet around the door frame.
The emphasis is on heavy tho, second hand woollen blankets hot washed then hot tumbled to shrink and felt them up, a double layer and weighted at the bottom.
Most cavity sliders are really lightweight paper honeycomb construction also; is it possible to add extra mass to the door or have it rebuilt with a foam core?
 
Moondog55,
I will give the wool blankets a try. I found some on Amazon that were not super expensive and it will be easy enough to hang for testing purposes.

At present there isn't a door, it's open to the laundry room. I would need to build a door and some type of a guide system for a sliding door. I don't have room for a 48" (1.2meter) wide swing door.

Thanks,
Scott
 
You could build a sliding door that pivots into the jamb when it closes, like sliding doors on vans etc, but I doubt you'll find a ready-built mechanism.
Or would you have room for a 24" swing? Start with a 48" door, hinged as normal, then split it down the middle and add hinges.
 
Sliding door mechanisms for exterior walls of facades almost always have a lifting function. In closed position the door rests at it's rebate, the weight of it pushing the seal to prevent gaps both up- and downside. The door obviously needs some kind of profile on top for this.

Door locks for such doors also have a clamping mechanism that pulls the door into the side rebate, closing the gaps there too. All of it boils down to $300 on gear for a good close and some handiwork to make the seals, so by no means it will become a cheap door. A well-known manufacturer here is Gretsch Unitas.
 
You could build a sliding door that pivots into the jamb when it closes, like sliding doors on vans etc, but I doubt you'll find a ready-built mechanism.
Or would you have room for a 24" swing? Start with a 48" door, hinged as normal, then split it down the middle and add hinges.

Don,
Something along those lines would work like a bifold closet door.
I think I'll start with 3 or 4 layers of moving blankets hanging across the opening just as a baseline.

Thanks,
Scott
 
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Joined 2008
Paid Member
Working totally from my own picture of your two rooms, how about a door with pivot in the centre of the top and bottom (Approx 2' mark) and the pivots can slide along tracks (much like typical bi-fold doors for closets but would need to be heavier duty) , one above the door and one underneath. Then you only need 2' clearance into each room for the door. Pivot the door open, slide it to whichever side works. Just a thought.
As an example , a more sophisticated version without a floor track can be seen Here and installation vid Here but raised with wheels off the floor, noise has an open path through. Maybe best to go with the in floor track and ramp up to it.
 
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Joined 2004
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Hi Scott. An interesting challenge you've got there.
  • Sound proof
  • Non standard size
  • Sliding
  • No room for top support.
OK then. :p Our house has 4 sliding glass doors that work fairly well to reduce outside noise such as loud neighbors, lawn mowers and such. Of course they all have both a top and bottom track, the weight resting on the bottom track and the top track mostly just keeping the door upright. All of them have seals at each end and the "handle end" fits into a small pocket or ledge. Standard stuff.

What I can imagine for you is a track in the floor to roll on and at the top instead of the rollers being above the door, the rollers would be on the inside top edge of the door with their matching tack along the wall face, or even countersunk into the wall. Perhaps 3/4" from the top of the door. You could use whatever little bit of room you have above the top of the door opening and the HVAC vent. If there is none, you might have to build something across the very top of the opening losing a bit of height.

At the handle end of the door you'd want it to fit into a flange or pocket as sliding glass doors do. A deep pocket would help seal off the sound. On the other end there's not a lot you can do except flexible seals. The more the better. You also want seals top and bottom as much as you can.

A few years ago I had to build a decoupled wall in my converted garage listening room because that wall faced a very noisy street. The decoupled wall worked extremely well, once built any noise then came from places other than the wall. Maybe a door with two panels and a gap in between would be as effective. For example; 1/2" plywood skins with air, foam or other insulation between. It's best to keep as few hard connections as possible between the two sides, the hard connections transmit sound.

Food for thought.