I’m trying to add some R-value to my downstairs ceiling. I live in a 1.5 story house. There are storage areas upstairs along the front and back of the house.  The insulation under the flooring is the only insulation over a good portion of the downstairs ceiling.

I’m taking up the plywood floor in the storage areas to deal with some settled blown-in insulation.  I was thinking about using some type of structural insulated panels as flooring rather than just plywood.  Has anyone used these panels for any type of flooring?  I first saw them used as siding on a “net-zero” project on a TOH tv program. I could always get rid of all the “stuff” and just add insulation I guess.