I have some ground EPS. How would that work in the attic?

Loose bead EPS is very air-permeable, and would deliver ~R2-2.5 per inch provided you add a topside air-barrier or a 3-5" overblow of cellulose. Without a topside air barrier winter performance would be miserable due to convective losses. In a loose fill it doesn't take much air current to re-arrange the piles of ground up EPS into drifts (an other reason for constraining air-barriers or a higher-density overblow.)

In the UK they have blown EPS bead products with integrated adhesives for retrofitting masonry cavity walls under pressure for a denser pack/lower convection potential, and they get about R3/inch out of it. EPS-cement panel products (commercially available in Asia) run about R1.5-R2/inch, but are far more air-tight, since the spacing between the beads is cement, not air.

I have only about 50 cf, should I mix it while I blow in the cellulose? we are blowing in the cellulose as I type this.

I blew it in on top of the spray foam, and will put 16" of cellulose on top of it.

I should have mentioned, I got it for free, I can get all I want, wish I had more. I wonder if there is a market for the use, as I did it.

I would mix the cellulose and beads together. Say 50/50. Then sell it as a solution to cellulose sometimes being too heavy.

Styrene beads in a cellulose blower might have some "intersesting" and not necessarily pleasant consequences. The amount of static charge that it might generate could be very exciting indeed! (Selection of the polymers for blowing hoses has some static-generation issues too.)

Posted By Dana1 on 04 Nov 2011 04:57 PM
Styrene beads in a cellulose blower might have some "intersesting" and not necessarily pleasant consequences. The amount of static charge that it might generate could be very exciting indeed! (Selection of the polymers for blowing hoses has some static-generation issues too.)

Ha!

Can you imagine the guy on the end of that hose?

Might there be any issues with the thermal/ignition break codes as well?

+1 to just running with cellulose.  If weight is an issue, you would probably be better suited to fiberglass with a cellulose cap.

The fire retardents in the cellulose would probably make the mixture meet code. As little as three inches of wet-spray cellulose-only overtopping would meet even the letter of the law, and ICF_construction's 16" of dry blown cellulose on top makes it a "who cares" proposition, even without a fire-ratings test. (If it's already burned through 16" of fire-retardent loaded celluose even if the firestorm winds are blowing half of that away, what are the odds that the house is still standing?)

Missed the part about the 16" of cellulose on top. That make the point moot and my question unnecessary.

I sent the EPS through the blower, no problem, right onto the spray urethane. I put the 16- 18 inches of cellulose over it. Isn't the 15 minute fire barrier over foam, just for living-spaces?

Living space requirements are higher from the thermal barrier standpoint whereas the attic/crawlspace only require and ignition barrier.

The drywall ceiling (provided it is 1/2") is providing the thermal barrier from the living space whereas the cellulose will provide the ignition barrier.

Cellulose does not appear to be mentioned specifically in the code but it is consistent with the code and like Dana said, more than sufficient enough.

When I was an insurance adjuster I saw cellulose that had burned well, in patches. I was told the fireproofing is often mixed in inconsistently.

We only blow the CellPak Supreme with Borate stabilization and I have done the torch test on it. Inconsistent in spots might be an issue but that stuff didn't want to combust at all.