Building and Construction - Insulation Manufacturers

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Insulation Manufacturers - Which to choose?

Engnrguy

2006-06-26, 5:25 pm

Hello all.

I am trying to choose between Insulation quotes but each company is
using different insulation manufacturers. I checked on the specs of
each manufacturer and they all seem relatively the same.

I have read that some copanies are pure fiberglass while others are a
wool fiberglass mixture. This is for my new home in Swansea, MA.

My questions are:
What do you use when your building a home?
Is there a particular brand or company you stay away from?

Dick Russell

2006-06-29, 9:26 am

Engnrguy wrote:
> Hello all.
>
> I am trying to choose between Insulation quotes but each company is
> using different insulation manufacturers. I checked on the specs of
> each manufacturer and they all seem relatively the same.
>
> I have read that some copanies are pure fiberglass while others are a
> wool fiberglass mixture. This is for my new home in Swansea, MA.
>
> My questions are:
> What do you use when your building a home?
> Is there a particular brand or company you stay away from?

Since you are building a new structure and have expressed an interest
in getting it right, you perhaps ought to go beyond the immediate
question of type of insulation. I assume you are interested in more
than getting a low bid. Choice of insulation should be a part of
complete wall design, and that includes location and post-construction
integrity of the vapor barrier; proper installation and flashing of
windows; integration of siding, housewrap, and any rainscreen
provisions. It all works together, so all of the wall components should
be designed together. Spend a lot of time researching the subject on
sites like this and others.

One problem with some types of insulation, such as fiberglass, is that
they collapse and become far less effective if they get wet, and that
is where proper installation of housewrap, windows (with respect to
flashing - web sites claim 90% of windows in the country are not
installed and flashed correctly), and vapor barrier come into play. If
your vapor barrier is installed diligently, then punctured all over the
place during wiring, plumbing, and sheetrock installation, then in
winter you have moisture moving through the wall assembly, across a
temperature gradient until it hits the dew point and you have
condensation.

As you search further, you'll see comments about the effectiveness of
insulation being diminished by as much as 50% by air infiltration on
cold and windy days in winter. In the case of fiberglass insulation,
even with no air infiltration high temperature gradients in the dead of
winter can result in small circulation currents within the batt, due to
differences in air density on the warm and cold sides of the batt, and
any movement of what should be dead air within the insulation cuts into
its effective R value. Blown cellulose is tighter and far less prone to
this, and foams are even better in this respect.

A case can be made for foam insulation, but it costs more. You'll see
discussions of both open-cell foams, such as Icynene (R about 3.6/inch,
but less costly) and closed cell polyurethane (R 6.5 to 7 per inch, but
more money). Both are vapor retarders, both will block infiltration of
air in bulk, and both will give more total R value in the wall than
will fiberglass.

Finally, if you wind up with a well-designed wall that is
energy-efficient and protects the insulation from moisture from both
inside and outside, you'll have a tight house, and that in turn means
you'll need fresh air for the occupants. That calls for a heat recovery
ventilator and appropriate ducting to serve the whole house. Don't let
the builder tell you that the house "needs to breathe a little." That's
an ill-informed way of saying the house may have to be deliberately
leaky and energy-inefficient to compensate for moisture getting into
the wall cavity from improper design and construction of the wall. The
problem with making the house "tight, but not too tight" is that on
cold windy winter days the house will leak far more, on mild windless
days it will leak very little, and in any case you'll never know
whether the leakage (expressed as air changes per hour, or ACH; 0.3 to
0.4 is a good working number) is too much or too little, and whatever
it is you'll have absolutely no control over it. Put in the ventilator,
and you can dial up whatever air change rate you need for comfort,
health, and humidity control.

Do your homework. Don't rely on the builder to get it right, because
far too many of them just do things the way they've always done things.
There are plenty of sites providing good advice on building science
these days, and a number of forums that regularly toss around ideas on
wall design. You'll also see discussions of the horror stories that
result when the wall wasn't done right for the environment around the
house.

Enough soapboxing. I'll let others comment on what I've said. I'm sure
there will be plenty.

Engnrguy

2006-06-29, 9:26 am

Thanks Dick,
I have taken into account all of these issues.

I choose better built Pella windows and doors as well as purchasing the
flashing type tape to seal around the windows before they side the
house. I have thought alot about sealing gaps and voids in the framing
as well as around the windows, on the inside, with the expading foam
for a better seal. (I actually purchased almost a dozen cans to be sure
I have enough. Also I am asking the builder to fix or cover and holes
or tears in the Tyvek as he goes. (I am thinking about also adding the
foam under the vinyl siding so as to have two layer of material between
the siding and the wall.

I priced the Icynene and it is well beyond what I can aceive with my
budget. I tried to cut things out of my budget, like cear impressions
siding, the really BIG fireplace, and nice counter tops inorder to
upgrade the things that matter over time BUT I still can't fit the
icynene stuff in. That is why I was asking about the insulation
manufacturer. I would like to know if one company has a better product
with regards to longevity of the product and its ability to insulate.

Dick Russell

2006-06-29, 9:26 am

Engnrguy wrote:
> Thanks Dick,
> I have taken into account all of these issues.
>
> I choose better built Pella windows and doors as well as purchasing the
> flashing type tape to seal around the windows before they side the
> house. I have thought alot about sealing gaps and voids in the framing
> as well as around the windows, on the inside, with the expading foam
> for a better seal. (I actually purchased almost a dozen cans to be sure
> I have enough. Also I am asking the builder to fix or cover and holes
> or tears in the Tyvek as he goes. (I am thinking about also adding the
> foam under the vinyl siding so as to have two layer of material between
> the siding and the wall.
>
> I priced the Icynene and it is well beyond what I can aceive with my
> budget. I tried to cut things out of my budget, like cear impressions
> siding, the really BIG fireplace, and nice counter tops inorder to
> upgrade the things that matter over time BUT I still can't fit the
> icynene stuff in. That is why I was asking about the insulation
> manufacturer. I would like to know if one company has a better product
> with regards to longevity of the product and its ability to insulate.

Sounds like you are doing some of the smaller building tasks yourself.
Nice that the builder is cooperating with that. My thought on the use
of a foam board between the siding and sheathing is that it would be a
second vapor retarder, but on the cold side of the wall. That would
tend to keep water vapor trapped within the wall cavity. I have been
following a thread on another forum recently on the issue of Tyvek and
its effectiveness as a water resistive barrier (WRB). It is known that
unprimed cedar up against polyolefin vapor barriers can release natural
solvents out onto the WRB surface and degrade it. There is much back
and forth on use of #15 felt in addition to the Tyvek as a means of
protecting the Tyvek, so that it becomes just an air barrier to keep
infiltration out of the insulation. On another thread, which began last
fall and wound up this past spring, a lady near Philadelphia described
an extensive residing to a fairly recently constructed house, due to
water leakage around improperly flashed windows, and the resulting mold
problem. She had done extensive investigation of installation and
materials issues, probably far more than the builders that had been
involved. She wound up stripping all the siding off, reinstalling all
the windows (properly flashed this time), and using HomeSlicker
(www.benjaminobdyke.com) between the housewrap and new siding.
HomeSlicker is a mesh product either 7 or 10 mm thick (1/4 or 3/8 inch)
that provides a rainscreen design; the air gap between siding and
housewrap allows any water that does get behind the siding to run down
freely and, perhaps more importantly, allows the space behind the
siding to dry after the rain ends. The 10 mm version meets the Canadian
requirements for rainscreens in the Pacific Northwest area, where they
get a lot of wind-driven rain in the course of a year. I've been
considering that product for my own project, a couple of years off.

As to type of insulation to use, if I don't go with something like
Icynene then I probably will use blown dry cellulose, because it has
slightly better R value and when blown to the recommended density (3
lb/cu.ft.) it doesn't allow thermal currents to develop when the
temperature gradient is high, as on very cold days. With either
cellulose or the pink stuff, keeping water out of the wall cavity is a
must, unless the wall itself is left very leaky so as to promote
drying. But leaky walls and energy efficiency are mutually exclusive;
that's why I said earlier that the whole wall needs to be designed as a
system, and a tight house needs a heat recovery ventilator. Good luck
with your project. Let us know what you decide.

marson

2006-06-29, 9:26 am

seems like what the OP is asking is what are the differences betweens
brands of insulation i.e. owens corning vs john mansville. i assume he
is speaking of fiberglass. i've never heard that it makes a
difference. i have noticed that some brands are dustier than others
(john mansville especially). that would affect the installer more than
the homeowner.

regarding the foam on the outside, while theoretically it is a vapor
barrier on the cold side, in actual practice it has proven to be a good
way to go. what happens is that the sheathing is warmer and thus can
keep the stud cavity above the dew point, which is a good thing. many
people have done it...the proof is in the pudding. if i was going that
route, i would take extra care with my vapor barrier as an added
precaution.

yeah, icynene and blown in blanket are great ways to go, for them that
can afford it. the rest of us have to settle for fiberglass.

Engnrguy

2006-06-29, 9:26 am

marson wrote:
> seems like what the OP is asking is what are the differences betweens
> brands of insulation i.e. owens corning vs john mansville. i assume he
> is speaking of fiberglass. i've never heard that it makes a
> difference. i have noticed that some brands are dustier than others
> (john mansville especially). that would affect the installer more than
> the homeowner.

This is exactly my question. I can't fit the Icynene in the budget. It
is determined that Fiberglass insulation is my only affordable option.

> regarding the foam on the outside, while theoretically it is a vapor
> barrier on the cold side, in actual practice it has proven to be a good
> way to go. what happens is that the sheathing is warmer and thus can
> keep the stud cavity above the dew point, which is a good thing. many
> people have done it...the proof is in the pudding. if i was going that
> route, i would take extra care with my vapor barrier as an added
> precaution.

This seems to be an oft debated question. I think I may have to just be
sure my contractor recovers any gaps or cuts in the tyvek and is sure
the wrap in homogenous, or as much as possible. I will seal gaps and
things from the iside with foam and what not, at least as much as
possible.

> yeah, icynene and blown in blanket are great ways to go, for them that
> can afford it. the rest of us have to settle for fiberglass.

That is me, unfortunately.

So the question remains...Are there any brands or manufacturers that
you prefer or stay away from? I have heard Knaupf is a mich of wool and
Fibeglass. JM is 100% formaldahyde free. The other are just Fiberglass.

Any other thoughts? I can't seem to find ANY information online about
differences between brands.

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