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One of the processes I’ve been researching is slipforming papercrete. All the slipforms I’ve seen to date have been non-porous construction. Why is noone making porous forms for something with such a high superfluous water content? I’m sure it’s the cement forming mentality, by why hasn’t anyone stepped beyond this mindset?

I am picturing slipforms that will fit over the existing wall, clamping onto the foundation or previously formed wall for stability.

Maybe someone can/will comment.

The slipform could be constructed out of perforated metal sheeting or heavy screen tackwelded onto a frame of tubular steel. Each form would require two sides. This is looking at the frame from the side.

Welded U’s of tubular steel would act as the brackets that would hold the two screened forms together. Welded pins would fit into holes in the brackets locking the top of the form into shape. Below is a cross section of the cross bracket installed onto the form walls showing the pin location. A handle mounted at the top would assist in setting and removing the brackets.

If the forms were small enough they could be made out of sealed pegboard and 2×2s with sun shade cloth stapled onto the inside of the form walls. Making the forms out of metal would allow the forms to be larger, but larger is heavier, and heavier is not always better. A combination may be the answer, sun shade cloth covered peg board and 2×2s with metal cross brackets. For smaller wooden forms cross cuts of heavy u-channel metal might be sufficient to hold the forms in place against the weight of the papercrete.

It sounds like it’s time to do some experimenting. Let the games begin.

As it’s a given I’m going to have problems being allowed to use papercrete as a structural element, I’m going to have to use a hybrid system that will give me the strength of ferrocement and the insulative and acoustic values of papercrete. I’ve hit on another protocol I feel is an improvement on my previous method.

In building my tiltwalls, each will have to be build in stages, starting with the papercrete which takes the longest to dry.

I will have to do testing to ensure I know to the nth degree what the rate of shrinkage will be before I lay up the papercrete portion of the wall. Also, I need to know how long it has to set to be strong enough to pick and lay aside without damaging the wall.

Once the papercrete layer of the wall is movable, it’s pull off the layup table and the ferrocement layer is then assembled. As soon as the concrete is floated on/vibrated in, the 1″ foam layer is placed on top followed by the papercrete layer with it’s embedded connectors, pressing the foam onto and the connectors into the ferrocement layer.

The only issues I see with this series of steps is the connectors. The connectors will have to have a point on the end to sneak the end between the elements of the different the layers of reinforcing in the ferrocement layer. It is conceivable that drilling holes in the foam to accommodate the connectors is not necessary. Simply laying the papercrete with embedded connectors on the foam (with some judicious walking on top) will be sufficient to push the connectors through the foam and into the ferrocement layer. Testing required . . .

I’ve been away for a week, and between getting ready, being gone and getting back, I haven’t had time to post.

I’ve joined the papercrete list on yahoo to try and glean as much as I can regarding papercrete. I’ve read some reaffirming stuff and some interesting stuff. Nobody’s doing what I want to do yet. We have 8″ of snow on the ground, so I’m obviously doing nothing but research right now, but I’m itching to get going.