YES!! This is one of our favorite applications. In the winter time, those of us with raised houses suffer from cold, moist wood floors & in the summertime we lose much of our conditioned air through cracks in our floors. Applying our product under the wood floors or under subflooring not only creates an air seal & insulates the floor, but it also seals all the cracks, crevasses, & holes where rodents, roaches, & spiders enter our homes. The foam also will protect your wood floors from soil moisture rising from the ground to slowly rot your wood. Installing fiberglass batts under your floors can be a huge mistake because they tend to drop a few inches creating an air gap where moisture can penetrate & wreak havoc on your wood, not to mention creating a more pleasant environment for termites & rodents. Although there are differing opinions on closed cell v open cell for a subfloor application, our experience is that closed cell is a preferable (but more expensive) product for a subfloor in our climate. Most building scientists & manufacturers agree with this opinion. Although we have never encountered any issues with open cell foam underneath a raised house (& we think it is much better than fiberglass), closed cell is more preferable in our opinion. I (the owner Kirk) have closed cell foam under my own house but have open cell foam under a few of my rental properties.