Ivan wrote:
I was in HD today looking at insulation. I saw something new (to
me). The propaganda on a certain brand claimed it had extra "sound
proofing" qualities.
The product was green and seemed softer than the regular pink
fiberglass insulation. Not as soft as Charmin, but still softer and
almost woolly. Does anyone know about this brand? Would the sound
proofing qualities be that much more than pink fiberglass? I'm going
to be stuffing insulation in the joist cavities in a down stairs room.
Ivan

It appears it helps a little. Even standard insulation helps a little.

How happy you will be depends a lot of the type of the noise and the
construction. High frequencies and low frequency sounds don't react the
same.

Generally the best and cheapest answer is increased mass. An additional
layer of drywall is usually the biggest bang for the buck. Lead blankets
behind the drywall helps a great deal, but cost more. Isolation techniques
that provide a break from one surface to the other (like staggered studs or
isolation strips) can be very useful.

Often the problem is a result of the sound taking a short cut. Any air
to air connection is going to be a problem. Heating ducts and cold air
returns are a prime example. It is also important to consider that the
sound might find it easy to go up through the ceiling, across and down
through the ceiling in the next room.

Windows and doors are also common problems.

If the source is very local like a washing machine, that can often be
addressed directly.

Take a look at:

http://www.soundproofing.org/

For some ideas.

--
Joseph E. Meehan

26 + 6 = 1 It's Irish Math