Re: Demilec versus Icynene

[Guest guest]

Are these spray foams worse in fire than fiber glass?

>

> Hi folks,

> >

> Both manufacturers are providing two spray foam insulation. Spray

> polyurethane foams can be engineered to be applied over a range of

> densities. The compounds they release fall into three categories:

>

[Guest guest]

Sam - The guys really pushing foam insulation the hardest are those

who sell it - go figure. The difference between a flash foam and full

foam cavity is the flash foam leaves room for standard fiberglass

insulation. The combined use increases insulation performance by

eliminating air leaks and increases the R value a point or two. Most

builders are using foam only in specific areas to address

penetrations and areas where air leaks are common.

The challenge associated with full foam is the HVAC engineer must pay

attention to tonnage and overall system performance. You cannot go by

tonnage alone, but must also take into account the manufacturer's

system performance numbers. The potential problem is moisture buildup

due to short system runtime. If you have too much system, you do not

achieve proper dehumidification and moisture problems mount.

Also, it is a good idea to include an air exchanger/energy recovery

unit to maintain some degree of air exchange. I have seen a few homes

so air tight that bathroom and kitchen ventilators are of little use

and fireplaces cannot be used without opening windows.

There are a few reports trickling in about moisture problems

associated with foam. Not having seen the problem for myself, it is

not clear if the problem was actually caused by the foam itself or

some other factor.

In any regard, foam has its good and bad like any other building

material. One has to pay attention to PERM ratings with wall

assemblies. Having built long enough to remember EIFS, foam has a lot

of proving to do before many of us will accept it.

Forum Question - Has anyone around here sampled the offgas for

analysis? The odor is noticeable in new homes with full foam. Being

more VOC conscious these days, the offgas is a concern.

Will

> > As a builder, we do not recommend a full wall cavity application

of

> > closed cell foam. With a PERM rating of 16 to 18, there is a

concern by > many experts that this can increase moisture loading in

the wall cavity.

>

[Guest guest]

Terry,

Thanks for your feedback. The contractor we are working with had some 1' x 1' samples of the closed and open cells sprayed for me that I've kept around the apartment. I didn't really notice any thing one way or the other. But I suspect that a whole house being done would be a totally different experience. I will ask him about visiting some place if he has something newly sprayed. Many thanks,

Sam

From: Terry Brennan terry@...

No formaldehyde from the polyurethane foams.

[Guest guest]

Thanks Bob,

Really appreciate the feedback and I will ask for the msds. If you come across it, please do forward it on to me.

Many thanks,

Sam

Suggest you keep looking. There is some off-gassing. The real question begins when you cant seem to get the question answered. Somewhere I have the MSDS and if I were you I would ask for it. The mixture MSDS (its available).

EnviroBob

[Guest guest]

Thanks very much Ron. It would be most appreciated. I spoke a while ago with some people at Demilec but they had little idea about off-gassing and health issues they gave me the number of my local rep and despite calling a number of times, never heard back.

Sam

Sam for information on Icynene call