Most wall insulation is made of materials that don't soak up water:  fiberglass, foam board, foam pellets, perlite, etc.  Even a small leak could turn papier mache into a moldy, slimy, wood-rotting mess.  And you might not know about it right away.

Ground paper is used in attics because there is usually more covering (wood + tarpaper + shingles).  I would seriously hesitate to use even that in walls.  Frozen water in roof gutters can back up under the shingles.  Splashed water could work its way along the foundation.

I think you should stick with standard insulation materials in this case.

Sue

thanks so much for the replies after a couple of days i was worried no one would. I realize standard insulation is less likely to be damaged by water however fiberglass in particular can soak up a lot and prevent it from escaping eventually rotting the wood as well.Blown cellulose insulation is gaining popularity and is essentially a type of mache with a binder added to provide fire retardant,papercrete uses the concrete as a fire retardant and water protection for the paper fibres and is probably the sturdiest bet but i don't like concrete. I am probably dreaming that anyone else thinks it's a good idea but might just have to go for it anyway. I'll keep you guys posted if it does or doesn't work out and maybe you will see me back with some mache art on the walls of mache when all is said and done.Thanks again and if anyone else has any bright ideas or concerns i still could use em daved

Sheeps wool insulation ... accept no alternatives

mold wrote:

Hi i am building a gallery and am seriously considering papier mache as an interior finish for the walls including the insulation. Basically ive used typical stud construction with 2 by 6 lumber and plywood sheathing covered with cedar shingles on the exterior and want to fill the cavities where one would normally put fiberglass insulation with papier mache  with lots of air space for insulation and then finish it with more of a pulpy mixture to get a hard more plasterlike finish. I am having trouble finding information about this though ive found a bit on papercrete which is basically paper mache with concrete for strength as an exterior surface, i am opposed to using concrete though. I am hoping someone out there could help me decide how crazy or possible this idea is. I would like to use wallpaper paste without fungicide but am a little worried about mold on such a big project, if i did it in layers and allowed it to dry thoroughly could i avoid fungicides. I was thinking of using a insulated water bottle carrier mixer for the mache and crumpled newspaper for the airspace insulation part then throwing smaller bits of paper into the mixer with the mache for the finish coat. I live in BC western canada and would appreciate any input or help with sources for wallpaper pastes as well as strategies towards construction. I have a fair bit of papier mache experience but have never attempted anything like this thanks daved

CatPerson wrote:

Most wall insulation is made of materials that don't soak up water:  fiberglass, foam board, foam pellets, perlite, etc.  Even a small leak could turn papier mache into a moldy, slimy, wood-rotting mess.  And you might not know about it right away.

Ground paper is used in attics because there is usually more covering (wood + tarpaper + shingles).  I would seriously hesitate to use even that in walls.  Frozen water in roof gutters can back up under the shingles.  Splashed water could work its way along the foundation.

I think you should stick with standard insulation materials in this case.

Sue

There have been some legitimate objections to the papier maiche idea based on absorbancy issues, but I actually think that it's a great idea worth pursuing but that you do have to be careful about the absorbant properties. What about blocking any water damage by using a protectant covering of some sort?

Shellac springs to mind, you might be able to just shellac the bejesus out of it. You might also consider having a 1/16" plexiglass covering on top of the maiche. It depends on your most interested in the texture or the look.

Definitely I am curious if there are other ideas to prevent the paper from getting soggy and rotten, I think it would be quite a beautiful wall with a lot of character.