Yes, this product can be used in conjunction with rigid foam. I hope this helps.

The initial R-Value on the Great Stuff products is 4.3 with an aged product at 18 month R-Value is 3.6. Please be advised that the Great Stuff products are designed as an air sealant product not as an insulation product. Using the Great Stuff products in large quantities is not recommended. Great Stuff is designed for use in gaps and cracks ONLY. Great Stuff foams are moisture cured and they form a moisture-proof skin as they cure. The skin (like the shell of an egg) blocks the interior of large sections from receiving moisture eventually resulting in a pool of liquid in the centre of the foam. Layering Strategy: it is possible to fill a large void with Great Stuff foam if it is applied in layers. The layers should not be more than an inch thick and should be allowed to fully cure (1 - 2 hours) before the next layer is applied. Hope this helps.

Great Stuff (TM) are designed for use in gaps and cracks ONLY. OCF foam Great Stuff (TM) are moisture cured and they form a moisture-proof skin as they cure. The skin (like the shell of an egg) blocks the interior of large sections from receiving moisture eventually resulting in a pool of liquid in the center of the foam. Layering Strategy: it is possible to fill a large void with OCF foam if it is applied in layers. The layers should not be more than an inch thick and should be allowed to fully cure (1 - 2 hours) before the next layer is applied. While the foam is often advertised as forming a "waterproof" bond between most substrates, it is not designed for constant exposure to water. The Compressive Strength of the Great Stuff (TM) products is 6.4 psi so the foam will not support the weight of the bath tub or the water in the bath tub. You should follow the recommendations of the tub manufacturer.

The GREAT STUFF (TM) Big Gap Filler insulating foam sealant is a cream colored foam but it is paintable, stainable and sandable.

Great Stuff ™ foams are not designed for underground applications (foundations, insulating pipes, tanks, etc.), the foam should not be exposed to UV light or constant flow of water or it will break down over time. While the foam is often advertised as forming a "waterproof" bond between most substrates, it is not designed for constant exposure to water, the foam should be coated with a waterproof coating or painted once the foam has fully cured, and that takes between 8 to 12 hours.

OCF foams, Great Stuff (TM) should not be used around any heater, furnace, fireplace or recessed lighting fixture where it contacts heat conducting surfaces. The foam will burn if exposed to open flames or sparks from high energy sources such as a welding torch, and it will start to thermally degrade if exposed to temperatures above 240F for long periods of time. The cured foam can handle ambient temperatures up to 240F before thermal degradation starts, which means the foam will break down and could begin to burn. Please make sure that any surface that the Great Stuff (TM) foam comes in contact with stays within the temperature limits stated.