Exiting Walls in Homes,
Apartments or Condos
in New Construction
is a form of energy. The more energy produced in one place, the greater
effect that energy will have in another if it is allowed to get there.
a stone = Energy expelled
Get hit by a
stone = Energy received !!
The harder the
stone is thrown, the more it hurts !
are three ways of stopping the stone hurting.
something very dense, the stone will bounce off. You may feel the
dent where it hit, but its effect will be reduced.
2:- Wear something
very thick and soft, the power of the stone will be absorbed by the
softness. You may still feel the stone, but the force will be greatly
3:- Get to the
joker with the stone.
principles can be applied to sound. Unfortunately its a little more
complicated because differing frequencies ( Bass, etc) of sound, produce
different energies (frequencies) and need to be dealt with in slightly
different ways...If the stone above was very sharp, small and pointed,
it may well pierce the protection, whereas a larger, flatter stone would
The two sound
control options come with many variations, basically they can be divided
into the areas below.
When sound passes through an acoustically absorptive material like
mineral wool insulation or acoustic foam, the sound waves are forced to
change directions many times and travel great distances before the sound
passes completely through the absorptive material. Each time a
sound waves changes direction, a portion of the energy is absorbed by
conversion to heat. When there is a reflective surface behind the
absorber, (such as a wall) the sound which passes through the absorber
will be reflected back and through the absorber once again. Absorbers
work best when there is some sort of a reflective surface behind them.
For some sounds (low frequency) an air gap is ideal between the absorber
and the reflective surface or wall.
A noise barrier can be constructed from almost any non porous material.
Since sound is energy, an effective barrier must have enough mass
(weight and density) and a low resonant frequency to stop (or reflect)
this energy. As sound pressure levels increase so does the sound
power (energy). High sound power levels will excite any surface
they encounter causing the surface to vibrate at its resonant frequency
which inevitably makes the walls shake. Low frequency sound
contains more energy, because a larger volume of air is being displaced
to produce the long wavelengths associated with bass and sub bass
frequencies. These low frequency sounds easily excite most common
building materials like wood and 3/4" thick drywall.
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Foam Soundproofing for existing
or Apartments and Condos
FOMO Foam Slow Rise (SR) pour
in place foam insulation is designed with a delayed foaming agent. One
of it's many uses is to fill walls in existing homes or apartments and
condos to isolate noisy areas or walls connecting to noisy neighbors.
Simple to use.These kits will
fill approximately 200 square feet of 2x4 wall with 16" on center
studs. See how to figure how much you need HERE.
This foam is high-density foam,
and is often not the most economical soundproofing
for between floors. Cellulose insulation dense-packed between floors is
suggested as one excellent and economical solution for those living
below high traffic areas. The fact that, for foam to be effective, you
have to fill what is often 8" to 12" floor joist cavities, a cellulose
insulation contractor will be able to dense pack cellulose for effective
sound insulation in the floor cavities much more economically.
In the walls, Fomo Foam works great
for sound control. High-density foam is also an excellent air seal. The
odors of cooking and smoking will not penetrate wall cavities insulated
with FOMO Foam!
The Slow Rise formula is easy
to use and comes with the patented HANDI-GUN® and hoses attached. You
simply drill 3 one-half inch holes in the first two cells you are going
to insulate. One hole 1/3 up, one hole 2/3 up, and one hole near the
top. Then drill the holes in the rest of the wall except only put 2
holes in each cell. One hole halfway up and one hole near the top.
Now that you have all your
holes drilled, you simply make sure you have a tip on the gun and rock
the cylinders for a couple of minutes each, turn on the valves on top of
both tanks to full open and slide the tip of the gun into the first hole
1/3rd up and hold the trigger down for 15 seconds.
Have a rag handy to plug the
hole in case the foam starts coming out of the hole. The SR formula is
designed to stay lava-like until it flows down to the bottom of the cell
then starts rising up the cavity. It will take the path of least
resistance and completely fill the cavity from the bottom up. After
about a minute and a half, the 15 second burst you put in will be
completely risen. If it started pumping out of the hole, you can tap on
and feel the wall to gauge how high it rose. Adjust your timing for the
next 1/3rd and then do the top third.
If there is blockage or old
insulation or a thin wall, the foam may hit the opposite wall and stick
until it gets heavy enough to fall. It won't harden or set for 90
seconds and is designed to come out at a gelatinous or lava like
consistency. If this is the way it works for you, and you find
obstructions are a problem, then simply get some
5/16" hose 50' at a Home Depot or hardware store and
slide a one or two foot piece of the hose over the end of the gun and
slide that into the hole pointing down. Then go to the hole above,
called "witness holes" and spray down to the first hole until the
foam meets. If it's still rising, that's okay. It'll just keep pushing
up. If you use the hose system, you will need to use a new 1 or 2 foot
section on each cell or cavity just so the hose doesn't become so foamed
up it creates a mess when you take it out of the wall.
Normally, in most wall
assemblies, this is not necessary. Also be aware that some walls were
built with cross pieces as fire blocks in the cells. Of course, this
will "feel" like an obstruction, but just drill below it and
fill that isolated area. Some people like to use the hose system
for more control of where the foam is going. It's a personal preference
and your decision.
You are probably going to have
to replace the tip after the first hole. If you stop spraying these kits
for more than 30 seconds, the tip may clog up. You can tell because the
trigger will be hard to pull. DON'T force it! Your kit comes with 8
extra tips. If you force it you will cause the gun to freeze up with
backfilled foam. You can use 4 or 5 tips in the first 3 cells to get the
feel of how it is going to expand in your particular wall assembly.
Then you fill the rest of the
cells halfway up and return to the first unfinished cell and do all the
top halves. Doing it steadily in smaller increments from cell to cell to
cap them off is the best way to do it. It's easy and not at all messy.
Just be ready to hold something over the hole if you put too much in.
It'll still rise UP if the hole is plugged. If you REALLY get crazy and
put in way too much at the top, have a bucket or paint tray or something
ready to catch the excess that may not have anywhere else to go except
out of the hole. The top hole acts as a pressure valve. If it has to go
- it has to go. Let it. Just don't make the same mistake twice. ;o)
Smaller layers means more
control. Just do it steadily across the wall and back...and forth...
until the cells are capped off.
Then patch your little 3/4 inch
holes, touch up the paint and be proud of your job.
That's all there is too it!
Relevant Mr. Foam Inquiry:
Mr. Foam, my question is: I own a home that was built in 1968 and has
little to no insulation in the wall. Could you supply me with a math formula to calculate how much
product I should purchase? An
example of what I want to insulate is an existing wall that is
approximately 8ft tall by 14ft wide. The studs are 16" on center. From the "Existing Homes" page it appears that I
should order the "Slow rise" formula. Is that correct? Thank
you for your help!!
Yes, the SR formula is the right
formula. Calculations are simple enough once you understand that the
product numbers (II-100, II-200 & II-600 SR) correspond to board
foot (12”x 12” x 1”) coverage, i.e. II-100 yields 100 board feet,
II-200 yields 200 board feet and II-600 yields 600 board feet.
If you have an 8’x 14’ foot
wall to drill and fill, multiply 8x14 to get the total square footage
(in this case = 112 sq. ft.) subtract any doors or windows and multiply
times the depth of the cavity. If we assume you have 3.5” 2x4s (most
aren’t TRUE 2x4s, but actually 2”x 3.5”s) and there are no windows
or doors, you would multiply 112 times 3.5 which equals 392 board feet.
To fill the 8’ x 14’ foot
wall above, you would need 2 of the II-200 kits. This product is
significantly less expensive in the II-600 kit. For example, 2 of the
II-200 kits will cost $660.34 whereas one II-600 kit (30% more coverage)
only costs $700.00, in effect giving you a free II-200 because it’s all packaged in one kit. One 600 kit is yield equivalent
to 3 of the 200 kits.
Your energy savings will be very
significant. Any leftover material can be put into a lot of areas that
need attention. Sill plates in the basement or crawlspace, for
instance…where the basement or crawlspace walls meet the floor where
the floor joists lay on the wall.
I hope this answers your
questions and wish you a well-insulated day!