Soundproof for sex

[Lexii]

Based on their situation, soundproofing is the best solution. Any other potential problems should be answered by the wife.

Customer: I want to buy a car.
Car Sales: No, you can leave instead.

Love the car example!

Yes, I (TS) am the "wife." Sure, I can be quiet, and sometimes it can be exciting to be quiet, but always being so is mentally exhausting; it negatively affects sex too because the husband likes to hear my reactions. 🤷‍♀️ I don't want to get used to the default "quiet" mode, as then you can't even react/sound genuine anymore after a while.

Also, I think a bit more rough sex can be heard too (e.g., spanking) and is much harder to explain than moaning.

Oh right, the bed headboard/bed banging is not a problem, but it was until we removed the bed frame and switched to a soft headboard.

 

[Lexii]

An idea is to send the kids to grandparents, friends for sleepovers, etc when there will be some louder activities. A classic.

Then they would need to sleep over 3-4 times a week. No one wants them that often, and moreover, we don't want to disrupt their home routines too much, and otherwise we enjoy having our children at home.

 

[Lexii]

[link]

Yes, we have looked at these before. My question remains - what do they actually do? Do they make a significant difference? It feels like they would dampen but not completely isolate, so the question is how much do they dampen. Do you have any experience with them?

 

[Rabbithole]

The method for soundproofing existing rooms is quite simple.

- Ensure it is airtight, apply a layer of plasterboard on all surfaces, putty and seal. Floors, walls, and ceiling. A sound-rated door is good, and having 2 doors is also advantageous. Ventilation is often an issue, and you can reroute it to a space where noise is less of a concern.

Ideally, ensure that the noisy room is somewhat remote from other rooms. Then you can make room for additional wall framing,

- Tightness (no gaps in the wall either near the sound source or where it should be quiet)
- Thickness (greater distance between 2 walls provides more reduction for long sound waves like bass sounds)
- Absorbers (reduce echo, all rooms)
- Mass (requires more energy to set in motion)
- Decoupling (vibration isolation, structure-borne sound)

It is quite common only to focus on walls. Walls are often reasonably tight with plasterboard, wallpaper, etc. Ceilings, however, often have small gaps that leak sound. Floor structures are often quite open, allowing sound even up to the attic.
Sand is loose and heavy. Typically very poor at transmitting sound. It's something you can use at the bottom of a sealed floor structure.

Doors, ventilation, windows, the large sound reflector in the room.. and then there are radiators with steel pipes that go to the next room..

Take a room... install a smooth, quiet outward-opening door that is tight (sound-rated). Seal the installation. Cover the door with carpet.
In the room, plasterboard all surfaces, floors, walls, ceiling, putty, and seal. Completely airtight.
Tightly glue 50mm ground insulation boards (compact mineral/rock wool) on all surfaces, floors, walls, ceiling.
Lay chipboard flooring across the entire room.
Frame new walls on the chipboard flooring, all surfaces, including the outer wall. Install beams for a new ceiling in the new wall studs. Ensure there's a gap between the new walls/ceiling and the insulation, the more distance, the better. Fill the spaces between the beams with regular mineral wool, not packed, still with a distance from the ground insulation boards.
Close the walls and ceiling with OSB+plasterboard, putty, seal. Possibly floor plasterboard.
Install inward-opening quiet door.
Install inner windows in the new inner room (decoupled from the house structure).
Cover with surface layers, preferably wall-to-wall carpeting everywhere.

Home theater, music studio, or a passion chamber, it doesn't matter.

You can also create "white noise" near the person who is sensitive to sound, such as a fan, so sudden noises are somewhat drowned in the noise.

 

[Rabbithole]

Yes, we have looked at these before. My question remains - what do they actually do? Do they make any significant difference? It feels like they might dampen but not completely isolate, so the question is how much do they dampen. Do you have any experience with them?

Pure isolation covered with acoustic fabric makes a bigger difference. Perfect for reducing airborne sound in the same room, e.g., echo in a Pod studio.

 

[spikplanka]

Ventilation is often a concern and you can direct some to a space where it can make some noise.

It's not really a big concern, but you can't use standard techniques. In a project to dampen machine noise, I got a tip from a doctoral student in acoustics.

The method involves building the ventilation ducts like a labyrinth with internal damping matting; if the air is supposed to be for indoor air, you should probably line these with geotextile or something like building plastic to prevent small fibers from detaching and to prevent mold. Then there's the important part of constructing the ducts with asymmetric shapes and lots of bends. One method to build this sound trap is with wooden studs covered with explicit soundproofing material, and as a base, you use a larger robust board. Then add geotextile over the damping mats to ensure that no material follows into the room. Also, a "lid" that is screwed on and can be removed to clean from dust.

For a room or house, you should probably use steel, etc., instead of wood considering mold risks, etc.

If the room is being remodeled for the stated purpose, it might be worth arranging ceiling beams where you can mount something to attach ropes, etc.
However, remember to distinguish between static load like a cement bag hanging still and dynamic load where you drop a cement bag and it is slowed to a stop. Dimension accordingly.

If mineral wool or glass fiber is used, remember that these release small fibers that happily penetrate cells and create inflammation until, in some cases, cancer forms.

To test the sound dampening, you might, for example, play some "forbidden film" at high volume.

How old were the children when they started getting interested in the strange sounds?

 

[Rabbithole]

It's not really a big issue but you can't use standard techniques. In a project to dampen machine noise, I got advice from a doctoral student in acoustics.

The method involves building the ventilation channels like a labyrinth with internal damping mat; if the air is meant for indoor use, you should probably cover them in geotextile or something like building plastic to prevent small fibers from coming loose and to inhibit mold. Then the important part is to construct the channels with asymmetric shapes and lots of bends. One way to build this sound trap is with wooden boards covered with specific soundproofing material and for the base, a large sturdy board is used. Then, geotextile on top of the damping mats to secure that no material escapes into the room. Also, "lids" that are screwed on and can be removed for cleaning out dust.

For a room or house, it's probably better to use steel instead of wood due to mold risks, etc.

If the room is being redeveloped for the stated purpose, it might be worth organizing ceiling beams to which something can be mounted to attach ropes, etc.
But remember to distinguish between static load, like a cement sack hanging still, and dynamic load, where you release a cement sack and it’s stopped to a standstill. Dimension accordingly.

If mineral wool or fiberglass is used, remember that they can release small fiberglass particles that happily penetrate cells and create inflammation, leading to cancer in some cases.

To test the soundproofing, you might consider playing some "forbidden film" at high volume.

How old were the children when they started getting curious about the strange sounds?

Building good sound dampeners is a bit of a witchcraft (and depends on the sound spectrum). You also have to make sure you don't create a lot of flow-induced noise, but with many absorbers and volume, you don't need much of a labyrinth. There are quite good foam materials (like Poron) that dampen sound waves really well. Fiberglass is cheap and not super effective. Also must be covered with a surface layer.

 

[sjoelund]

Building good silencers is somewhat of an art (and depending on the sound spectrum). You also have to ensure that you do not create a lot of flow-induced noise, but many absorbers and volumes don't require much of a labyrinth. There are fairly good foam materials (like Poron) that dampen sound waves really well. Fiberglass is cheap and not super good. And must be covered with a surface layer.

At least you don't have to avoid echo when it comes to this problem. So it's not like soundproofing a recording studio.

However, we are moving and starting to think about how to consider things when looking at houses.

If multiple floors are relevant: look for something with concrete between the floors. It helps a lot with vibrations from the bed and is very hard to hear through between the floors other than through ventilation. Most other comments seem to be more focused on walls that are easy to address afterward if needed.

 

[spikplanka]

There is quite good foam material (Poron, for example) that dampens sound waves really well.

Looked up what Poron is, "open-cell polyurethane" but it seems there are variants with closed cells as well. Suitable place of purchase?
Density between 104 - 480 kg/m³
Temperature resistance -20 to +121 ⁰C

I seem to recall that open cell works poorly with moisture so it will probably need construction plastic or similar on top.

Do you know if there is any continuous material that converts mechanical vibrations into heat instead of absorbing the mechanical energy elastically and sending it back?

 

[Rabbithole]

At least you don't have to avoid echo when it comes to this problem. So it's not like soundproofing a recording studio.

If multiple floors are involved: look at something with concrete between the floors. It helps a lot with vibrations from the bed and it's very difficult to hear well between the floors except through the ventilation. Most other comments seem to be more focused on walls that are easy to fix afterwards if needed.

Concrete flooring also acts like a drumskin. Vibrates at the slightest thud and transfers structure-borne vibrations enormously. That's why an inner floor is often laid on a layer of insulation.

You don't need to worry too much about echo if you have absorbers in the silencer. But it's good to be aware of the angles of incidence and reflections of the sound.

 

[Rabbithole]

Looked up what Poron is, "open-cell polyurethane," but there seem to be variants with closed cells too. Suitable place to purchase?
Density between 104 - 480 kg/m³
Temperature resistance -20 to +121 ⁰C

I believe open cells work poorly with moisture, so building plastic or something similar on top may be needed.

Do you know if there is a continuous material that converts mechanical vibrations into heat instead of absorbing the mechanical energy elastically and sending it back?

Open cells work quite well. With open cells, you get less reflection on the surface and sound waves penetrate the material better.

Moisture... yes, but such moisture load and even dirt should not be present. A filter before the sound attenuator is good. Unless you just run a hole behind a removable screen.

I have to pass on the purchase location. I've only purchased directly through the job's supplier. Amazon is probably the easiest. It's better to go for density and low price unless there's limited space.

Ideally, you want shearing between two layers in the material that creates friction. There are no super materials here, really, that are sensible to prefer.
Hard surfaces to block/steer reflections and then just fill with absorbent, as deep as the lowest frequency.

 

[spikplanka]

Preferably, you want shearing between two layers in the material that creates friction.

I was wondering if Tempur would work by absorbing mechanical vibration and returning it as heat.
Maybe a fabric consisting of 1 mm rubber alternated with thin sheets from a foam mattress?

 

[sjoelund]

Concrete floor slabs are also a bit like a drum skin. They vibrate from the slightest thud and transfer structural vibrations enormously. Therefore, an inner floor is often laid on a layer of underfloor insulation.

Sure, but it's relatively easily fixed if you have a thick, nice concrete slab between the floors. At my place, you can have an entire football team upstairs, and you won't hear anything between the floors. It helps not to have pipes between the floors for radiators like in older apartments - they also become easily sound-conductive.

 

[spikplanka]

it's relatively easy to fix if you have a thick nice concrete slab between the floors.

What does this fix consist of?

It helps not to have pipes between the floors for radiators as in older apartments

How do you arrange the pipes between the floors without sound following them?
If it shouldn't be unheated that is..

 

[sjoelund]

What does this fix consist of?

Lay the floors over the concrete according to what I replied to.

How do you arrange the pipes between floors without transferring sound?
If it doesn't need to be unheated, that is..

You place them where no one is. In my case, air-borne underfloor heating. A pipe that goes straight from the closet to the shunt and doesn’t go up into any of the rooms upstairs, so there are no vibrations it picks up.

An alternative is LLVP; then you have no water-borne heating to install and therefore no sound that travels between floors.