My 1950 bungalow has no insulation:(. I have researched and decided to blow in densed-packed cellulose insulation in between the exterior walls from drilling underneath the siding, but am still unsure what to do with the attic space. The unfinished attic areas along the front and back sides of the house have accessible storage, and someone did place batting side in R19 fiberglass insulation in between the roof studs, but it is disinigrating. The floor is a double-decker type wood setup with a space about 4-6" between the two wood levels. Could I just blow in the slow-rising polyurethane foam insulation into this floor space? If so, should I leave a certain amount of space between where the foam between the floor and the roof edge meet for an air gap? And then should I leave the roof stud areas without insulation, for air flow? I'd like to leave the floor space accessible for storage if possible, and I'm concerned of a mess if I spray cellulose on top of the "top" floor, and also concerned about smashing fiberglass insulation by sitting boxes on top of it. Any helpful comments would be greatly appreciated!