Anyone using "air crete" for sheds?

[newbury]

In my never ending quest for inexpensive building materials I'm looking into "air crete". Basically a mixture of cement, a "bubble agent" and water. Aircrete is fairly light, has good insulating quality and strength. A good bubble agent is liquid hand soap.

Lots of you tube action.

One guy is making panels about 90" x 16" x 3.5" and they weigh about 66 lbs. each (or about a bag of cement). This is a one person manageable weight (for me). He shows how to build a "foam gun" for $30 (which he sells for $125).

So for a 12x20 shed I'd need about $600 of cement for the walls.

If any TBN'er is doing this I'm wondering what size wall sections are you building, how, etc.

I could see pouring a floor then building a 2x6 "frame" 6'x8' then pouring wall sections which I could lift with my tractor.

So any trusted TB experience here?

 

[EddieWalker]

Cement as in Portland Cement, or is that concrete, a mixture of cement, sand and gravel?

How do you get any strength out of it, or keep it together, or stop it from cracking?

 

[4570Man]

I’m not seeing it costing $600 to frame the walls of a 12x20 shed. 4x8 concrete siding sheets are pretty cheap. I don’t see you saving any money and adding a bunch of work.

 

[stuckmotor]

The other day, I took a peek at the panel guy and wondered how strong they were. Maybe I should take another peek.

 

[GirlWhoWantsTractor]

These alternative building materials are kind of cool. Papercrete, aircrete. Sounds expensive and a lot more work versus a framed structure, but should be strong and possibly rodent-proof. Will be interested to see pics if you do it.

 

[newbury]

I’m not seeing it costing $600 to frame the walls of a 12x20 shed. 4x8 concrete siding sheets are pretty cheap. I don’t see you saving any money and adding a bunch of work.

I wasn't looking at so much as saving $$ but more as an alternative to typical stick or concrete block building.

I'd be eliminating most 2x4's. I've a present former chicken coop that's about 10x12 made out of concrete block, so it will blend right in.

One of the main things is it looks easy to do, there is a lot of "air crete" building effort in underdeveloped countries. It looks like it may be possible to make buildings without forms but more research is needed.

Here's a video of building one in Europe

.

It would be like making your own block, just making them a lot larger.

 

[jfh28]

as with all concrete construction.......concrete is very strong in compression but lousy in tension......thats why steel reinforcing is added to floors walls and footings.......in your case 20' will be to long of a distance without reinforcing or some kind of pilaster system and once you start getting into that you might as well just frame it with 2x4's and be done with it.......Jack

 

[RNeumann]

Just did some rough math and the weight doesn’t seem to be adding up. “Normally” a slab the size described would take over 8 60# bags of premix concrete. But the stated weight is equal to one bag- this means adding soap will somehow expand the concrete to over 8 times its non-soap equal.
I’ve only been in and around construction for four decades but I’ve never seen this method. Not saying it won’t work or shouldn’t be tried- just saying the results may different then the theory.

To experiment we are talking about $20 for the forms, concrete and soap. Why not give it a whirl and report back! Interesting idea- concrete sponge!

 

[bcp]

Is it just solidified cement with bubbles? No sand, gravel, or fiber? Doesn't sound like it could be very strong.

Bruce

 

[newbury]

Just did some rough math and the weight doesn稚 seem to be adding up. 哲ormally a slab the size described would take over 8 60# bags of premix concrete. But the stated weight is equal to one bag- this means adding soap will somehow expand the concrete to over 8 times its non-soap equal.
I致e only been in and around construction for four decades but I致e never seen this method. Not saying it won稚 work or shouldn稚 be tried- just saying the results may different then the theory.

To experiment we are talking about $20 for the forms, concrete and soap. Why not give it a whirl and report back! Interesting idea- concrete sponge!

What is the

slab the size described?

The one video where he goes through the math (painfully) he calculates 66 pounds of cement needed for one "form" or slab 90"x16"x3.5" at about 19 minutes into the video.

Plugging the numbers, 90" x 16" x 3.5" = 5,040 cubic inches which equals about 22 gallons.

From

1 bag of cement (unknown weight but probably 94 lbs) makes about 50 gallons, enough for two slabs.

For comparison an 8' x 4' x 4" slab would take about 80 gallons of space so about 160 lbs, maybe 200 w/ rebar.
(GAD why can't we work metric????)

The foaming agent doesn't "expand the cement" it just takes up a lot of space with very little weight.

I'm mainly wondering about "tweaking" the process, several places mention "additives" such as polymers, lime etc. and if any TBN'ers have experiences.

And Bruce:

Is it just solidified cement with bubbles? No sand, gravel, or fiber? Doesn't sound like it could be very strong.

Bruce

No it seems they usually add some screen or mesh or fiber.

 

[EarPlug]

Out of curiosity I browsed Google. One interesting thing I saw was that in Europe they use KILN Dried panels. This probably adds a lot of strength like brick making.

 

[newbury]

Out of curiosity I browsed Google. One interesting thing I saw was that in Europe they use KILN Dried panels. This probably adds a lot of strength like brick making.

Often it's AAC - Autoclaved aerated concrete

Aerated autoclaved concrete - close-up view
Autoclaved aerated concrete (AAC), also known as autoclaved cellular concrete (ACC), autoclaved lightweight concrete (ALC), autoclaved concrete, cellular concrete, porous concrete, Aircrete, Hebel Block, and Ytong is a lightweight, precast, foam concrete building material invented in the mid-1920s that simultaneously provides structure, insulation, and fire- and mold-resistance. AAC products include blocks, wall panels, floor and roof panels, cladding (fa軋de) panels and lintels.[1]

Not as much a DIY project where one dumps a bag of cement in with foam from detergent, stirs and lets it cure.

The AAC is great for multilevel buildings and commercial construction. "Air crete" seems to be a "hippie" version of AAC. Not really good enough to build a major building but should do fine for a shed.

 

[Navvet]

Look around you-tube some more ... Lots of info on air-crete. The one I liked used steel studs as a frame with wire mesh embedded in the concrete mix.

I have not tried this yet but am looking at it for an end wall for a Quonset building.

 

[stuckmotor]

Look around you-tube some more ... Lots of info on air-crete. The one I liked used steel studs as a frame with wire mesh embedded in the concrete mix.

I have not tried this yet but am looking at it for an end wall for a Quonset building.

Where would a person purchase a few steel studs? I've never noticed them at Lowes or Home Depot.

 

[GLyford]

My local HD carries them, they are in the same aisle as the sheetrock mud...I've not looked for them in lowes.

Drywall Steel Studs & Framing - Drywall - The Home Depot
Try hitting this link, and then checking the "pick up today in my local store" thingy. It will often tell you what part of the aisle they are in.

The other way is craigslist, people have a few left over from projects and list them.

 

[Navvet]

Where would a person purchase a few steel studs? I've never noticed them at Lowes or Home Depot.

I saw them yesterday at Lowes.