ACC Block (Autoclaved Aerated Concrete)
Last Post 05 May 2011 09:26 AM by jamesmacdonald1. 8 Replies.
Printer Friendly
Sort:
PrevPrev NextNext
You are not authorized to post a reply.
Author Messages
natliteUser is Offline
New Member
New Member
Send Private Message
Posts:1

--
15 Jun 2007 10:47 AM
Has anyone used ACC blocks by Contec, Austin, TX?
We are considering this product for our new warehouse.

http://www.texascontec.com/sitios_relacionados.html
myvillaasutinUser is Offline
New Member
New Member
Send Private Message
Posts:1

--
09 Apr 2011 10:23 AM
Hi
I am a home builder in Austin and I am completing a house built with Aerated Concrete blocks. My crew are specialists on the product. You can read more about the project on my website, www.myvillaaustin.com I cant imagen building wiht any other product, I highly recommend it.
AltonUser is Offline
Veteran Member
Veteran Member
Send Private Message
Posts:1978

--
09 Apr 2011 10:48 PM
I am quite familiar with AAC.  Some companies require their AAC blocks to be covered with a special mix - not just regular stucco.  Having a well-trained experienced crew can make a real difference in savings of material and time.  Untrained crews often make mistakes that will cost the homeowner.

Although I have seen AAC used for basements I do not think it is as suitable as placed concrete is for strength and water resistance.  I know you did not memtion using AAC below grade but since this posting will be here for some time, someone else may need to know this.
Residential Designer & Construction Technology Consultant -- E-mail: Alton at Auburn dot Edu, 334 826-3979
jonrUser is Offline
Veteran Member
Veteran Member
Send Private Message
Posts:4382

--
09 Apr 2011 11:00 PM
Why is an autoclave necessary for these? An aerated naturally cured concrete isn't possible?
AltonUser is Offline
Veteran Member
Veteran Member
Send Private Message
Posts:1978

--
10 Apr 2011 06:23 PM

jonr,

I may be wrong but it is my understanding that autoclaving is curing under better conditions which can add to strength.  Maybe one of the concrete producers or engineers can set me straight if I am wrong.

Residential Designer & Construction Technology Consultant -- E-mail: Alton at Auburn dot Edu, 334 826-3979
jonrUser is Offline
Veteran Member
Veteran Member
Send Private Message
Posts:4382

--
10 Apr 2011 07:50 PM
It also speeds up production. But I did see another lightweight concrete block that only used foaming agents - evidently not aluminum powder or autoclaving.

But personally, I prefer EPS + a thinner layer of high strength concrete - 10,000 and even 15,000 psi are easily attained.


AltonUser is Offline
Veteran Member
Veteran Member
Send Private Message
Posts:1978

--
10 Apr 2011 08:16 PM

jonr,

SABS by StrataUS may not be quite that strong.

Residential Designer & Construction Technology Consultant -- E-mail: Alton at Auburn dot Edu, 334 826-3979
Baldwin2014User is Offline
Basic Member
Basic Member
Send Private Message
Posts:122

--
12 Apr 2011 03:05 PM
AAC blocks are great. Worked with them when I was 15.

some things you may want to consider:

they have very low compressive strenght - i think normally they are about 500-700psi maxing out at about a 1000psi. (normal stregnth concrete is usually around 2500 - 3500)
they absorb water like crazy. once they do they crumble like wet drywall.
over time the lower sections of wall on 2 storey homes start to crack and crumble...
really hard to waterproof and finish as they absorb moisture quickly
really hard to reinforce them
they have excellent thermal properities and inulating properties. but not enough insuatling properties to meet the code. so you will find urself furring it all out and adding foam.
jamesmacdonald1User is Offline
New Member
New Member
Send Private Message
Posts:92

--
05 May 2011 09:26 AM
Autoclaving is primarily for shortening the time before which you can handle the blocks. It makes them reach their strength faster (It might not necessarily increase the maximum strength).
I am not a big fan of AAC because it is primarily masonry construction, depending on mortar beds, etc. It is not as strong as a reinforced concrete wall (unless you reinforce and grout, etc). But even then masonry design codes are not as developed as reinforced concrete. The relative reduced strength is apparent in why you don't see AAC in basement/retaining situations.

Also, I don't like the idea of not having a separate insulation layer on the exterior isolating the structure from the exterior. I understand that it acts as both structure and insulation, but I think from a building science perspective it is better to have exterior weather barrier/finish, insulation, structure and then interior finishes. Because AAC is one material going entirely through the wall section, the problems that Baldwin indicated tend to occur more often than not.

Stick with ICF if you can.
You are not authorized to post a reply.

Active Forums 4.1
Membership Membership: Latest New User Latest: Rache@AECDaily New Today New Today: 4 New Yesterday New Yesterday: 2 User Count Overall: 28983
People Online People Online: Visitors Visitors: 225 Members Members: 20 Total Total: 245

GreenBuildingTalk

Welcome to GreenBuildingTalk, the largest, most active forum on green building. While you can browse the site as a guest, you need to register in order to post.

Register Member Login Forum Home

Search Directory

Professionals Products

Get Free Quotes

Tell us about your building project and get free quotes from green building professionals. It's fast & easy! Click here to get your free quote.

Site Sponsors

For Advertising Info:
Call 866-316-5300 or 312-223-1600

Professionals Serving Your Area:

Newsletter

Read the latest GBT Newsletter!

Copyright 2011 by BuildCentral, Inc.   Terms Of Use  Privacy Statement  Free Quotes  Professional Directory  Advertising Programs