[Greenbuilding] On Insulating Crawlspaces and Basements: BAD FOAM!

[Keith Winston]

Leslie, I'm sorry I've taken so long in responding. I was hoping to get in
touch with "Foam It Green" (FiG) to clarify some questions, but since that
might not happen (too busy) let me share off the top.

The "builders' kits" of foam that are made by many manufacturers appear
pretty similar to me: typical coverage is 600 sf (at 1") per set of
cannisters. They are propelled by refrigerant (in the case of FiG it's
R134a, a fairly common choice, an HFC refrigerant with near-zero ozone
depletion potential (ODP), and about 1/2 the Global Warming Potential (GWP)
as the original evil refrigerants R-11 & 12 (1300 vs. 2400 & 4000). That
said, I've had a new backround panic for years since they started selling
cans of R134a over the counter for people to recharge their (still leaky)
auto AC systems, which appears to have been borne out... atmospheric
concentration of R134a was shown to double between... wait for it... 2001 &
2004. It honestly feels like there are people trying to figure out how to
pump as much of this stuff into the atmosphere as possible.

So it's a very interesting question about how they offset their
contribution (previous research indicated that builder's kits of foam
release something like 6-12 pounds of refrigerant, probably, though this is
not easily discovered information in my experience). I also looked over the
MSDS for FiG, and was left a little confused: they list their components
slightly differently than most other 2-part polyurethane foams, but my
chemistry is not quite able to parse whether they are the same thing, or
just similar. Also, for trade secrecy reasons MSDS's don't include
everything, generally.

The argument for such a foam is that the energy saved over the life of the
structure more than justifies the environmental cost of the foam. Of
course, if you actually take that statement apart, there are lots of thorny
edges in there: what other options are there in a given situation, in terms
of insulation? building tightness? energy systems design?

The small can foam you get at a big box store is propelled by butane or
propane typically, with no ODP and a GWP of 1. That said, it can't be used
in large cans due to fire hazard I believe (though the chemistry of this
stuff can get complicated). And of course a thousand small cans would have
their own environmental impact, if you were trying to compare the two.
Careful and precise application of small cans (they can also be bought with
a specialized gun that allows very precise placement and the use of a can
over many months, vs. the challenge involved in saving a small can after
one application without having it cure up on you) seems like a rather good
use of this technology, in many cases.

Large commercial foam installers MOSTLY use a different kind of foam
(warning, some do not, they have huge tanks with refrigerant that they are
releasing when they foam), and the application thereof involves an
expensive device called a proportioner and heated hoses and the like. That
said, I believe some of them ALSO have refrigerants in the foam. In all
cases, these are called "blowing agents", and there are other options like
Ecomate
<http://ecomatesystems.com/ecomate-resources/Ecomate%20MSDS%20-%20MF.pdf>,
which is Methyl Formate and Methanol (both toxic, but they do disperse...
how thoroughly I'll leave to your own research & thinking).

Alas, I have not left you with a simple, obvious choice. There are many
more considerations I didn't even touch on, all the building
science/building health issues for example. Oh well. Welcome to my world!

Keith



On Sun, Jun 1, 2014 at 9:25 PM, Leslie Moyer <unschooler at lrec.org> wrote:

> Keith (or anyone),
>
> Do you know anything about "Foam It Green" as it relates to these issues
> (or others)?  It's a DIY spray foam kit.  They don't have too much info on
> their website....they are a member of the USGBC and "balance" their carbon
> emissions through Terrapass.
>
> On 9/9/07, 11:57 AM, Keith Winston wrote:
>
>> I don't have time to comment on your crawlspace issue, but I will say:
>>
>> Don't use TigerFoam, HandiFoam, and all other 2-part builder-applied
>> foams. Also, don't use contractors who use Dow FrothPak, which is the
>> same type of foam but in addition to small builder packages is sometimes
>> blown from trucks in large volumes.
>>
>> All these use refrigerants as blowing agents. They release 7-15 lbs of
>> refrigerants  (typically HFC's) for each 600 sf (board foot) package.
>> The Global Warming Potential (CO2 equivalency) of these refrigerants is
>> around 1500-2000, which means that those (nominal) 10 lbs are equivalent
>> to about 7-10 TONS of CO2 release. That will counteract at least the
>> majority of your CO2 reductions resulting from better insulating.
>>
>> I think this is a scandal that needs to be exposed. I have been talking
>> about it with many people (including people in the industry), but
>> haven't really figured out how to get word out. Until/unless we regulate
>> carbon emissions, there are no regulatory tools to apply (the
>> manufacturers changed from CFC's and HCFC's as blowing agents to avoid
>> Ozone/Montreal Protocol problems).
>>
>> "Good" PU foams are blown using a proportioner with heated hoses in a
>> truck, and water is the blowing agent. Even the little one-part PU foam
>> cans from Home Depot, etc, are powered by isobutane or other simple
>> hydrocarbons with relatively low GWP.
>>
>> I am now accepting donations to my legal defense fund ;-)
>>
>> If I have anything wrong here, I'd love to know. Constituents can be
>> (roughly) determined from MSDS sheets for foam products.
>>
>> Keith
>>
>>
>> Thomas Lewis wrote:
>>
>>> Hello All,
>>>
>>> I just purchased a home and am developing my project
>>> list.
>>>
>>> I would like to pose my plan for insulating the
>>> crawlspace and basement for your comment.
>>>
>>> The crawlspace is ~180ft2 with a dry layed stone
>>> foundation of unknown depth and ~2' thick.  It has
>>> been worked on over the years.  The exterior is
>>> pointed with a layer of stucco over that and two
>>> sections have been replaced with 8" masonry block.
>>> One section is a corner and the other is a four foot
>>> section with a vent.
>>> The crawlspace has ~6" - 36" clearance from grade to
>>> floor joist, all above exterior grade.
>>>
>>> The location is hudson valley ny, on top of a hill
>>> with clay soil, NE exposure.  The soil in the
>>> crawlspace appears to remain moist much of the time,
>>> but has not been wet yet and there are no signs of
>>> water damage on wood laying in there.  However, wood
>>> that is partially embedded in the ground is moist but
>>> with no signs of fungal or mold activity.
>>>
>>> My idea is to spray foam with 1.75 lb tiger foam. (I
>>> may just hire our local spray foam guys to do this,
>>> being that they have air supply masks et al)  Clean up
>>> all debris and remove a layer of soil, which is
>>> pitched to the center of the room from all points.  I
>>> will then dig a trench in the center, pour a small
>>> footing for a center post, repost the center support,
>>> then lay gravel in the trench and over cleaned floor,
>>> then cover the floor with polyethylene with standard
>>> lapping and sealing details.
>>> Based on lack of evidence of water, other than ground
>>> moisture, and the prospect of installing one into a
>>> place that I can barely roll over in when laying
>>> prone, I am opting to not put in a sump pump.
>>>
>>> I will install a 6" round, the kind with a weighted
>>> baffel, heated air supply to the space, with a return.
>>>   The basement is loosely connected to the air supply
>>> system, there is one 6" supply and one 8" return down
>>> there.  If I return the crawlspace air to the
>>> basement, will I pressurize the basement and
>>> depressurize the living space?  Its an old loose
>>> house, with many places where air moves between
>>> floors.  (I imagine the stack effect is pretty
>>> substatial here)
>>>
>>>
>>> I am haveing a bit more trouble planning for the
>>> basement insulation.
>>>
>>> Here I have 8' ceilings, the first four feet is stone,
>>> then on top of that I have brick.  The stone is below
>>> exterior grade and the brick generally starts 6" below
>>> grade and goes to 3' above grade.  I was thinking of
>>> repointing the interior where necessary, then spraying
>>> 2 lb. foam on the stone (~3") and a thin (3"?) layer
>>> of 0.5 lb. on the brick.
>>> .5 lb on the brick because I am concerned with
>>> reducing the brick's drying capability and with it
>>> getting too cold during the winter.  My thought is
>>> that if I insulate alot, it will be harder for the
>>> brick to dry and the exterior will get colder during
>>> winter and may damage the brick.
>>>
>>>
>>> My apologies, this email seems to have gotten rather
>>> long. Thanks for reading it and in advance for any
>>> advice you may have.
>>>
>>> Best,
>>> Tom Lewis
>>>
>>>
>>> "Time makes more converts than reason."  Thomas Paine, Common Sense
>>>
>>>
>>>
>>>
>>
>


-- 
Keith Winston
Director, Earth Sun Energy Systems
301-980-6325
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