Spray Foam in rim joists AFTER dense pack blown cellulose in walls

D107

A few years ago we had the walls in our 1920s balloon framed house filled with dense pack blown cellulose. probably reduced our heating bills 20%. in a few years when other projects are done we'll foam the attic eaves and gable walls. When we can open the basement walls, we also intend to spray foam the rim joists there.



It is the 2nd floor rim joists (at 1st floor ceiling) I'm concerned about. The cellulose worked fine but due to the balloon framing, the rim joists are wide open to the space between the plaster ceiling/lathing and joists, so much of the cellulose pours into that area, probably not under as much pressure as other areas. The 2nd floor wood floor near the walls is very cold. I've seen houses where holes are drilled into the 1st floor ceiling and rim joists are filled with the foam then sealed again. In this case an installer would have to carefully--so as not to cause too much densely packed cellulose to loosen--dam up the cellulose above and below the rim joist, maybe stuff some fiberglass up there to hold it up and then fill the space with spray foam. Has anyone ever done this?