Have You Laid AAC?

artisanstone

Looking for anyone with experience/advice on autoclaved aerated concrete block. I'm interested in general info about building with it. I'd like to get some experience with it and offer it as one of our services. I've researched it a good bit and it's captured my imagination as being a great way to build quality structures. I'm esp. interested in how masonry veneers are typically attached, what difficulties to expect with very cut up house plans, how many block a man can lay per day on a straight run, things like that.

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Bill Baddorf
Bill@artisanstoneworks.net
www.artisanstoneworks.net
www.stonefoundation.org

artisanstone

To elaborate; most of the new homes I work on are made to resemble full masonry structures. It seems foolish to me to build a 12,000 sq.ft. home out of little sticks and then try to make it look like it's built of stone, if you can spend just a little more and have full masonry that will last forever. Kinda like putting a ferrari body kit on a fiero. On that same note, some of my research indicates that galvanized wall ties have a life expectancy of only about 50 years. Does that sound right to everyone, and if so, why am I using them on 150 year stonework?

__________________
Bill Baddorf
Bill@artisanstoneworks.net
www.artisanstoneworks.net
www.stonefoundation.org

Tscarborough

First, re the ties: On stone, if they will pay, you should use stainless steel with any type of limestone. If not, HDG. In either case, be mindful of mating dissimilar metals (galvanic corrosion) via the screws.

In regards to the AAC, it is a nice material to work with, but it is not cheap. It is also not a finished surface, so it has to be veneered in all cases.

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It ain't Rocket Science unless you are building rockets.

bobcaygeonjon

Hi, I've used aac for over 20 years now but I work in the UK and have also worked in Canada and Germany. In the UK we lay the blocks using conventional mortar but that is a crap way of building. So I did a web search and found that in the US the manufacturers sell the same systems that they use in Germany using a thin joint system (like tile adhesive). I can tell you from my experiance that key to using this system is to get the first course absolutely perfect. Not good but perfectly level and plumb. That is the one drawback to this system as this takes a lot of time and dont even think about laying ontop until the next day. But once you start buiding corners and running in I dont think I'm exagerating if I say you can get in about 5 times the sq ft per day rather than conventional conc block. And it's light weight too. To cut the block you can use a hammer and chisel, hand saw but for lots of cuts you need power. a band saw is the best. Masonry veneers are built conventionaly using wall ties. The ties are either placed after build by drilling, inserting plastic plug and hamering or built into joints using purpose made ties.

Hope that has answered some of your questions but my question for you is why are you thinking of aac and not ICF (insulated conc form)?

artisanstone

Not to offend, but I love masonry and hate styrofoam. It's an aesthetic thing I guess.

__________________
Bill Baddorf
Bill@artisanstoneworks.net
www.artisanstoneworks.net
www.stonefoundation.org

Tscarborough

One job I have worked with AAC, they used 12" block with 4" stone veneer. For the interior, they rasped the AAC to seashell shapes above all the windows before applying hardcoat stucco. It came out lovely. There were several shows about that house, I will see if I can find one.

Laying AAC in mortar is just wrong. It needs to be laid with a thin joint using the proper thinset (not regular thinset). My only issues with the material are the fact that it is highly prone to chipping in shipment, and cost. The chipping is not really an issue from a materials standpoint, only from customer perception.

It is better in almost every way than regular CMU, Stone, or Brick, when used properly.

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It ain't Rocket Science unless you are building rockets.

artisanstone

What's the difference between AAC specific thinset, and the many varieties available for tile and stone flooring?

__________________
Bill Baddorf
Bill@artisanstoneworks.net
www.artisanstoneworks.net
www.stonefoundation.org

Tscarborough

The main difference so far as I can tell is that the aggregate is AAC dust. It is also probably formulated specifically for the (high) absorbtion of the AAC units

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It ain't Rocket Science unless you are building rockets.

bobcaygeonjon

Whenever we ran out of the aac thinset and had no time to wait around we would run out and buy tile adhesive but it had to be non waterproof. Dont know why, it's just what we were told.