As a consultant, I've specified products used by Demilec (http://www.demilecusa.com) for residential applications. They are manufacturers of open and closed cell spray foams, as well as intumescent coatings and other products. You can read about a few of their intumescent coatings on this page: http://www.demilecusa.com/technical-library/products
I'd recommend calling them for more information.
Great, thanks Brady! I think this is exactly what I am looking for.
this is a slippery slope.
if the intumescents are tested on a foam product, then that system passes the thermal barrier requirement. these systems are BRAND specific. you need an ICC ESR report indicating the specific combination of a brand of foam with a brand of coating. many foam manufacturers have relabeled a product called DC-315 as their proprietary product then tested that with their foam to get an ESR for the combination, but if you use the coating from a Demilec bucket on a Lapolla foam you technically do not have a code compliant product even if both manufacturers relabeled DC-315.
if you Google DC-315 you can pull down data sheets from at least 6 foam manufacturers showing a combination of their foam and some relabeled variant of DC 315. you cannot get ESR's there though, you would have to go to the foam manufacturer to get those.
Pat makes a good point, it definitely has to be a coating tested with a specific foam together as a system. I don't know if you are using high pressure spray foam or low pressure kits but if you are interested in a low pressure solution, Fomo Products' Handi-Foam has an intumescent coating Handi-Foam Ignition Barrier.
Learn more about it here: http://www.fomo.com/air-seal-accessories.aspx.
There is a training module available from our partners at No Burn that goes more in depth about the type of coating you would need for your application.
Best of luck! Let me know if you have any questions.