Spray Foam vs Cellulose Isn’t the Real Question! We hear this all the time: “I do spray foam, but I’ve never done cellulose. What’s the difference?” The truth is, they’re two completely different products, using two very different pieces of equipment and the equipment is everything. With spray foam, staying on-ratio is critical. That’s why professional foam rigs use sensors throughout the system to ensure consistency and performance. Cellulose works differently, but it’s just as equipment-depend