ferrocement using cinders?

[taropatch]

Aluminum cans laid side by side and packed with cement will work too. This guy in Puna was buying cans for his project. I asked him if he needed rebars for added strength and he said he did not use rebars. Have a pic somewhere on my other computer that he sent me.

[JWFITZ]

Hi Carol,

As others have noted, you can't use cinder for ferrocement as it doesn't have adequate compressional strength to match the tensile strength of the steel.

A very effective technique for backyard building that can save a great deal of cost and labor is to use concrete board as one side of the ferrocement structure, to use panhead screws to fasten the mesh to the concrete board(2 or 3 layers of mesh, depending on demands) and to mud that. It's much easier for an amateur or one working solo to only need to work one side of the structure. A 3 to 1 graded sand to mortar mix works. Try to keep it out of the sun because it can dry too fast and craze here pretty easily.

http://sensiblesimplicity.lefora.com/

[tada]

Believe me not trying to hijack anything I recall when they built the Real Goods store in norcal they put out a notice for everybody their old junk tv's or anything else and they buried it in the foundation. Don't know if the building collapsed or chemicals leached out. but sounds like something I'd do.

[mailesomaha]

We made our bathtub room walls out of a cinder/sand/ cement mix; although it wouldn't be considered "ferrocement". The walls are 18" thick and the room is 9 x 12 and is connected to our cmu house walls. It's the coolest and most sound proof room in the whole house and not a drop of rain has made it through even though it has a concrete roof and no overhang. We plastered the outside with fibercement and paint made for concrete.

We got the mix formula from an Army pdf file that we gave to the architect for permitting.