Southern Illinois Insulation is a family-owned and operated company which is ready to offer you the quality insulation work you expect.. By choosing Southern Illinois Insulation you'll be working with a business that is dedicated to providing you with high quality neat looking spray foam insulation! We cover things up as much as possible so we don't get overspray on your windows,doors, and floors. We also clean off the face of the studs so you can attach the drywall without interferance. We use a Quality foam that has a very high R value compared to other brands and has a very high fire retardant in compared to other brands.