Teardrops n Tiny Travel Trailers

If this has been covered my mistake. But why not go this route thru existing plywood

It will settle overtime and leave a void at the top.

It is basically shredded newspaper and while it is treated for fire it absorbs moisture... Our bricks and sticks built better than 100 years ago using a balloon frame (vertical frame with no fire stops) and no insulation was COLD or HOT until I found a company that could inject foam insulation. I had rejected the idea of Cellulose and even cubed fiberglass because of the settling and mouse habitat problems.

The cellulose used to blow into wall cavities in new construction is dense packed. It does not settle, is treated with a borate to protect against insects and small rodents. It is toxic to them but 6 times less toxic than table salt to a human. The borate is a natural mineral and also is a fire retardant and a mild / mildew suppressant. The type I like best is damp blown into the cavity between the studs before drywall is installed. The moisture helps the chopped cellulose stick together and stick to the outer wall, studs, etc. It has to be sampled for moisture content and signed off on before the wall cavities can be closed. Here that only takes a day, maybe two. It can absorb some moisture but that works 2 ways, it also releases moisture. I have a contractor friend who has used dense pack blown in cellulose in walls for over 10 years and has never had any callback issues.

In a house it does not settle. I have no idea how it would react to being towed, bounced, jiggled down the road. That could be a problem. Can't say for sure. I would put it in a new home but would not want to be the guinea pig for a trailer.

For all the trouble that would be involved with drilling holes in the plywood, finding someone willing and able to do such a small job and still not charge you an arm and a leg, filling the holes back up in said plywood afterward, why not just take the plywood down and stick a sheet of foam in there and be done with it? It is not that difficult!

Ditto MtnDon. My old house has that & it works great. After dealing with it doing some home repairs, I cannot come up with any way it won't settle in time if used in CT. But I'm always interested in being proved wrong, I can always learn a trick.

Its OK in a building that stays in one place, but road vibration will cause it to shake down and settle pretty quickly.

You also have more moisture in an RV application. Some of the chemicals used to treat the chopped newspaper for fire resistance are corrosive, and with the added moisture could adversely affect your wiring devices or your aluminum skin.