Ultra Lightweight Mortar or Concrete

Many air-containing aggregate components exist, such as perlite for the sand, and larger aggregates which are certain types of minerals what were kiln-heated to cause them to expand to a much larger size. The little reading I did on this suggests that most light-weight concretes are structurally much weaker than regular concrete, so the roof would still require structural support. Also, it will be more porous to water, so a water-repellent surface treatment or coating may be necessary.

I believe someone suggested adding powdered aluminum or something similar to the mix just before pouring it, because this would create many small bubbles as the added powder reacts with the alkaline concrete. Also, certain synthetic polymers make it easy to entrain air bubbles into the concrete, which again adds insulation value to it.

In the USA, try the portland cement association for further information. I like your idea.

You can also look into a process called ferro-cement which enables you to create much thinner structures. They too need to be supported. I know they build boats out of this but I don't know how lightweight you need to be

There are a number of companies that provide this. Try: www.siplast.com or www.celcore.com

They typically have a compressive strength of around 1/10 normal concrete. It also weighs about 1/4 as much as normal structural concrete. In new construction it is poured over a metal deck. The metal deck provides the structural capacity for support of the roof etc. It can also be poured over an existing roof. I am a Civil/Structural Engineer and a Registered Roof Consultant. I suggest you find someone with similar capabilities.

I read that you can use hemp hurds mixed with limestone to create a concrete mix far superior to regular concrete. Hemp concrete is lighter, stronger, and more flexible. Here is just one place I googled off the top of my head...

http://www.construction-technologies.com/lyfordg/Hemp/hemp.html

Why does it need to be light weight concrete? Even light weight concrete is still very heavy, and does not provide the insulation you can obtain by cheaper standards measures, e.g. fiberglass. Does the roof need to be a working surface?

Go to www.lightconcrete.com

This should help in addressing the problem. Inexpensive solution.

This is what we do better than anyone else out there. At 60 pounds per cubic foot I can give you 3510 PSI.

The product is fireproof and can be applied as low as 2.5 pounds per Cubic foot. (PCF)

It is a non portland binder. These results can not be acheived with Portland as the binder.

Adding aluminum creates and uncontroled fizz and a poor cell structure. What we use is a pre-formed foam which has caompatable chemistry with the two part binder. The strength loss which is normal when dealing with aerated Portland is mitigated.

tesla-was-right@hotmail.com

720-308-8906

Tesla-was-right

What are the sheer and compression strengths of your product compared with the portland product or other pozzolans? Also, how fast-setting is it, and how strong is it integrally (cracking, etc.)?

Do you have a comparison chart?

Mark

E-mail me or call and I will send the ASTM lab results. I do not know how to upload it here.

tesla-was-right@hotmail.com

http://www.alliedfoamtech.com/Appconc.htm

I am afraid I do not know who might supply foamed concrete here in the USA, but we used widely in the UK. It is very successful in its application and good quality foamed concrete will have a SG of ±0.6.

I hope you find a supplyer in the USA.

Regards.

John Mcfarlane