Cellulose insulation is nothing new. But I can attest to the mice bedding. How green is that foam if it burns? Something we all hope doesn't happen, but does occasionally.

How do these compare to recycled blue jean insulation? ... cool factor included.

Good point about the R-value. The effectiveness of insulation is measured by its R-value per inch- the higher the better.

Heatlok: R 6 per inch
Denim: R 3.7 per inch
Icynene: R 3.6 per inch
Procell: R 2.6 per inch (I think)

But also we should point out that batts like the denim always have more leaks and lower real world R-value when installed than sprayed systems that stick to the studs and really seal it.

I would want to know exactly what biocidal agent(s) are added to the sprayed cellulosic materials to prevent mold and such. If they were mineral and non-volatile such as sodium silicate that would be OK. But the devil is in the details when a preservative is involved. Show me an MSDS and we'll see how green it is.

How green is that foam if it burns?

I'm sorry, I didn't see the part that said that the foam is a fire hazard. Could you point out the passage that indicates that?

I also want to know where the definition of "green" is that mentions ability to burn.

Thank you.

The advantage of all kinds of spray insulation (over batt insulation, including the recycled blue jeans stuff) is that it seals against the studs, electrical boxes, etc and controls air leakage. Air leakage is often a greater source of energy loss than conduction through the walls, so this is a big deal.

For new construction this is all great. But what about an existing house? How can you fix those?

How green is that foam if it burns?

How flammable is it?

appart from being sustainable what are the toxic properties if there are any of the Heatlok soya system? The Icynene seems to boast no VOC's but i cant find that information about the Heatlok soya system.

To answer the questioner on existing homes, I myself had vacant areas between the studs of my 1960 Denver home. To fill them, I hired a contractor who drilled small holes (maybe 150% of the size of a quarter) into the mortar joints outside the house and then used a tube to force cellulose into the gap. After the work was done they filled in the mortar. It's hard to tell the holes are there unless you're looking for them. I know it made a difference, maybe 10% off of my heating bill. At that rate it will take many years to pay back, unfortunately. I also know that there are slow-rise formula foams that can be applied in a similar fashion, but they cost more. I've also had a friend who had a vynl sided house, who simply added a new layer of foam board and siding to the house. He said it has worked great. When considering insulating your house, remember that fixing leaky (air) areas typically has the highest return on investment.

I think what the poster is asking is, in case of a household fire, will the insulation in question turn into nothing but a toxic smog of chemicals? A valid point, since it DOES happen, though obviously not intended to.

we all know that homes burn. no insulation sprayed between studs is going to prevent that. i'm guessing that burning cellulose probably isn't as toxic as burning plastic/foam. the things we stick in our walls won't be used forever and what is done with any particular material at the end of its use is a totally valid factor to consider when evaluating how green a material may be. take a c2c perspective. can any of them be recycled? does the foam come off of the wood and pipes so that they can be reused?

on the other hand, i've heard that icynene (and probably some of the other foams) doesn't need a vapor barrier since it seals up so well.

besides spraying, icynene can be poured into wall cavities of existing structures, so retrofitting is often an option.

You know it burns and you know its toxic whether or not they say it, they're still petroleum-based. Air Krete does not burn and is made out of magnesium oxide which comes from brine. I wonder if the energy used in recycling the plastic would be less or more than what is required to make it from scratch?

If this stuff is so green why is the dude wearing overalls and breathing mask? Same with icynene.

I am in construction. I see people who cut plywood all day, mix mortar, cut brick, and install batt insulation. They never wear goggles or a mask (more important). They know the health effects. They know the glues are formaldehyde based, and that the dust from the mortar contains lime, and they know why they need to wear goggles because of the small fragments of stone over the years damaging their eyes. However, they will stay away from a house if being sprayed with insulation. That rings alarm bells to me, and it should to everyone.

Icynene isn't that green. It is a good product, however it contains isocyanates, which is a health hazard, which means you need to have an air tight house and a good ventilation system.

Whether any of these insulators burn or not, why does it matter how toxic it is? Anything that burns is toxic. The best advice is "who cares, get the heck out of the house".

The soy idea sounds good but it takes a lot of energy to recycle those bottles of water (banning plastic bottles for drinks would be a lifesaver)

I wouldn't use any of these products for retrofitting. You can't make your breathable house to air tight. It'll cause problems.

Simply put, figure how moisture moves through a 1940's brick house. Hollow wall construction, and foil backed drywall on the walls. Water moves through the brick and the airspace allows the brick to safely dry out. The foil backed drywall takes the heat and reflects it out. Not air tight, and works fine. Now fill with foam. First the drying process has a water shedding process. Where does the water go? Into the brick? nope, maybe a little, but it can't take that much water at that speed. Foil backed drywall can't take it either as it's water resistant. That leaves the studs. 55% moisture content on a house I did. Very very bad. Wood swells up at that point and will eventually dry out through air leakage (yup it's still there) and the brick. So once water levels drop, the wood shrinks and then there is an airspace beside the wood with excessive moisture content. Warm and dark, and now it's a mould farm. I've seen it. Now if the drywall wasn't foil backed, then we have that system drying into the house. Assuming there isn't any oil paint on the drywall or plaster, then it will dump that water into the house. If it does have oil paint then it simply puts that moisture into the drywall or plaster, with nowhere to escape. Model in different ways, and it typically has a failure point at some position in the wall.

Now how does that wall dry during normal use? Brick needs to move water through it to work. It can no longer do that as there is no longer an airspace behind it. Same with wood siding, etc. See the point. Heat and moisture transfer and simply it adds up that if the building wasn't designed to be airtight, it shouldn't be. I would recommend blown cellulose instead as it allows moisture to move through it safely, it can dry out, doesn't grow mold, is renewable, recyclable and is a healthy cheap alternative.

Air Krete is fireproof. However, everything burns at a certain temperature. Air Krete will just add more time (a lot more time).

the statement that the soya is zero ozone depleting is bs. the blowing agent HCFC 245 a is a greenhouse gas. it is manufactured by Honeywell and the MSDS clearly states that "Contains HFC-245fa, a greenhouse gas, a substance which may contribute to global warming."
direct from their msds

andy, the idea that a house has to breathe is decades old thinking. the mantra of building science for the last twenty years has been," build tight, ventilate right"
in other words build it as tight as you can and provide for controlled mechanical ventilation by HRV's, continuous exhaust systems etc.

Questions someone I hope can answer:

I have a 1950's one story ranch that I am going to add more insulation in both the walls and the attic. (I live near Buffalo.)

The house is app. 1,000 square feet.

I have a quote for $8,000 to have the entire house & attic insulated with air krete. I have another quote for $6,100 from another contractor using cellulose insulation.

A. are those quotes reasonable?
B. Is $1,900 more for the air krete worth it?
C. Is it ok to ask for a lower price than what they quoted me?

thanks,

Paul