Insulation between floors?

[DS]

In a 3 story house, is there any sort of insulation between the main/ground floor and the upper floor? Ie, is it (drywall ceiling), joists, floor boards, carpet; or is there something inbetween the joists to muffle sound?

Thanks

[David Efflandt]

In the 2 story I grew up in circa 1953 there was insulation (rock wool) between the floors, but that may have been because the upstairs was originally unfinished (my dad built upstairs bedrooms), so it was essentially an insulated ceiling between heated and unheated areas. I don't think there is normally any filler between finished floors.

[HA HA Budys Here]

Not normally, though blown in insulation is sometimes used to deaden sound between floors.

[Joseph Meehan]

Adding insulation will help some. How much depends on what kind of sound and where it comes from.

Generally insulation, even insulation designed to absorb sound does not help much.

For the sound of people or animals walking, carpet would be a good choice. To quiet a bed room over the TV viewing room an extra layer of drywall on the ceiling would do much more.

Take a look at:

for some ideas, or other sources.

In general you want to block air exchange. Air caries sound very well. (Try opening your car's window as a train is going by.)

Next you want weight. Heavy things (drywall lead sheets etc.) block sound well.

You also want to prevent any direct solid connections. Stagger wall studs or use special isolation devices to keep the sound from traveling through the wall (remember the two cans on a string (well wire actually worked) you want to break the wire).

Filling in wall cavities with sound absorbing materials (acoustical fiberglass bats) will do a little.

Point source control (special absorption material) at the source of the sound will also help.

[DS]

thanks for the link and the useful info... I'll check it out tomorrow in detail. Basically the plan is I'm refinishing a room in the basement which happens to be below the tv room and it has/had dropped ceiling tiles. Even with them in you hear almost everything from that room. Then again, my room at the moment is right above the same tv room and I also hear almost everything.. albiet a bit more muffled.

The only thing I think I can really do (without having looked in detail at the website) is to add some sponge pyramid stuff to the bottom of the above floor boards, and just deal with the stomping (there is already carpeting in the room above).

Any idea of a way to isolate the drop ceiling short of hanging it with elastic bands? ;)

Thanks

[Joseph Meehan]

The problem with dropped ceilings is two part. First they are not air tight. Air is great at transmitting sound. Second it is light. The frequencies you are working with are best slowed by mass (weight). This is were a double thick (two layers) drywall ceiling or a lead mate works great. You likely do not have the option of a drywall ceiling due to head room.

Another problem you likely have is the HVAC. Those ducts (supply and return) are thin skinned and let the sound pass right into them and then it is transmitted right to the room.

[DS]

Indeed, the panels are anything but air tight and they cannot be heavy, lest they fall on my head. And drywalling the ceiling of a basement I hear is a bad idea, for one because of the headroom issue, and second is access to the ducts and such for the future.

I was thinking of installing some mineral wool or pink fiberglass but apparrently it won't do much for the amount of effert involved. What about if I maybe just went and installed some of that 6mil plastic that is supposed to be put over the fiberglass.. that would create a bit of an air barrier, no? I'm just guessing on this one.

Agreed, but there really is not too much I can do about them, and from what I can tell they arent that big a conductor of sound.. the biggest really is from directly above the room.

Thanks