Jerry,
Please take my following comments as a FRIENDLY wake up call. I want to help, but I don't want to understress the importance of the issue being discussed either. I'm certain you are a smart and hard working guy. My comments are not intended to be personal, but I want to stress to everyone reading the magnitude of the issue. That is the only reason I worded things as strongly as I did. Some of these issues can be difficult to understand for many people when they encounter them for a first time. We have many first timers that read the messages posted to this group.
I STRONGLY suggest that you adjust your thinking.
I love papercrete, but it is not appropriate to use it in every situation.
Papercrete is excellent at many functions. Insulation, Materials Cost, Flamability (if the correct mix is used), DIY friendliness, Light Weight are all advantages of papercrete.
Papercrete IS BAD at some other functions. Tensile strength is one of papercrete's biggest weakenesses. It is very important to not use papercrete in a situation where the loads of the building will give it a force that will try to PULL on it.
While we can build structures that try to smash down (compression strength) on the papercrete all we want to (within reason), building structures where the paperete is expected to resist pulling isn't going to work well at all.
Bond beams NEED a combination of tensile (pulling) strength and compressive strength. The bottom of a beam always is under tension, while the top of the beam is under compression. I think it is safe to say that a bond beam is probably the WORST POSSIBLE application of papercete. This would potentially be even worse than using unsealed, plain paper in a wet environment. The potential for sudden catastrophic failure of a papercrete bond beam is substantial. The results of such a failure could be instantly life threatening. As nasty as mold is, at least with a mold situation there usually is a chance to leave the area for saftey. If a beam collapses, there may not be that opportunity to leave in time.
I encourage you to make a long block of papercrete and let it dry. Then support it on each end with a brick. Then stand on it in the middle. The result will demonstrate how papercrete will react as a beam.
My comments are not intended to discourage anyone from using papercrete in a structure, but to shed some light on how to use it WELL. Don't try to make it do EVERYTHING. As wonderful of a material as papercrete is, it simply doesn't have the ability to do it all.
I strongly suggest that you use typical standard materials for any beams. Properly sized structural wood beams are one choice. Steel beams are another. Properly designed concrete bond beams are also good. While concrete doesn't have great tensile strength either, it has the ability to bond extremely well to the steel rebar inside. It is the steel that provides the tensile (pulling) strength to the beam. Concrete bond beams are well understood and have been used for many decades. The concrete and steel compliment each other.
I wish you well with your structure. Please keep us posted with your progress.
--- In
papercreters@ yahoogroups. com, Jerry Fant <jerryfant@. ..> wrote:
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> Quick question:
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> I am building my workshop out of papercrete a 25 by 25 building. I am going to use concrete support columns every 8' and infill between them with pc blocks. When I reach 8' in height I was planning on capping the papercrete with a cement bond beam to bring the total height to 9'. Then it occured to me that I could use the papercrete to make the bond beam. What characteristics does papercrete have with rebar inside? What I am worried about is the shrinkage that I see when the block forms are drying.
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> Jerry
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