Talk:Autoclaved aerated concrete

Hello, Can we add HEBEL's Xella company as a website reference? -- —Preceding unsigned comment added by TMGroup (talk • contribs) 14:17, 27 August 2008 (UTC) In India BILT and B.G.Shirke andCo manufacture AAC in India. The products are very high in price though they claim that in AAC two of the most important cost components- material and energy consumption is low. How can a product consuming less material and energy be higher in cost? -- The above argument is only based on national experience. All kinds of aspects can affect the above question, even greed. The material AAC is almost equal in price to other wall building materials on the European continent. Of course for Indian marked you might take in consideration the cost of labor is very low compared to Europe and the coast for energy is assumable different to the energy expense ore energy efficiency during production in countries out of India. The article never state no where the production expense  outperform other wall building material worldwide.

However I agree parts of the article, with the exception of “ Raw Material” needs to be edited, as it lacks of substance and reads as a sales flyer. Sprockletwheel (talk) 03:00, 5 March 2008 (UTC)) 02:19, 5 March 2008 (UTC))

---

Less greenwashing, please! I agree that this article reads like a sales flyer; furthermore, the environmental benefits of this material are inflated by the writer. Not only is producing the raw materials for concrete notoriously energy-intensive, but this form of concrete cannot be produced on-site, so embodied energy from transport from factory to site must also be considered. Heat-curing the concrete in an autoclave must be energy-intensive as well. The lowered density increases its insulative value and strength; does it also make it less durable? These are all considerations in considering a product for specification. Perhaps someone with access to actual data on these parameters could edit the article. —Preceding unsigned comment added by 68.149.131.82 (talk) 18:26, 8 June 2008 (UTC)


 * When considering embodied energy of this product relative to poured concrete or concrete masonry units, keep in mind that AAC is mostly air by volume. Therefore, the actual Portland cement content by volume is very low relative to solid concrete or CMU.  I agree that this article sounds a bit like a sales pitch, but alas there is not a lot of information on AAC (in English anyway) that does not come from the manufacturers or distributors.  My understanding is that AAC has been very popular in Northern Europe for a long time, and so there may be more information available in other languages.  I would love to see some of it translated.  Randall Nortman (talk) 17:23, 11 October 2008 (UTC)


 * I agree that this article appears to be heavily slanted to the producers claims, without any counter information. I got here looking for an overview of the Radon gas issues of AAC that have caused most EU governments to provide special building regs for AAC block in dwellings, only to find that it was treated as a one off 'aggregate' issue, it isn't there are recorded issues with all AAC blocks emitting radon gas. Also to claim that anything that has cement as a constituent is ecologically friendly is misinformation, to put it mildy. It may be the case that 'comparatively' this is an innocuous product, but we should bear in mind that all cement produces its own weight of CO2 while curing, and much more during its production. The cement industry is the single largest specific industrial user of energy in the world, and is the second most consumed commodity globally, water being the first. AAC is not an ecologically friendly product, it is a partially reduced damage product. 81.111.39.70 (talk) 22:37, 26 May 2011 (UTC)

---

Since AAC is lightweight the amount of diesel consumed for that of transporting same volume of the concrete or clay brick is lower. The steel and concrete required for bulidng a structure is reduced because of lower vertical weight of walls with AAC bricks. Further more, the labor at the construction site is minimized as well as the time for construction is reduced (the walls made by normal clay brick take more time due to higher handling time of smaller sized heavier bricks than larger sized lighter AAC bricks). Due to its porous nature it has better soundproofing and insulating properties. Due to better insulating properties the airconditioning load also comes down. In all, the premium achieved by using the AAC is larger even if the costs of manufacturing are comparable to that of clay brick or concrete. —Preceding unsigned comment added by 59.90.212.46 (talk) 06:06, 10 June 2008 (UTC) -

Add copy?
Looks like it to me. --EmersonWhite (talk) 08:46, 18 June 2010 (UTC) - Hi, Maybe we could include also the fact that AAC provides very little signal attenuation for wifi networks (0~5 db). Source: https://www.bsi.bund.de/SharedDocs/Downloads/DE/BSI/Publikationen/TechnischeRichtlinien/TR03209/BSI-TR-03209-2_pdf.pdf;jsessionid=D3962E01AFD35C959EC9E5E1B5A02285.2_cid286?__blob=publicationFile — Preceding unsigned comment added by 2.81.203.160 (talk) 20:33, 6 February 2013 (UTC)

Horrible sound attenuation properties
A building where neighbors share walls made of aerated concrete is not fit for human habitation by developed country standards, as it does not attenuate the sound almost at all. Sounds made by physical vibration seem to travel especially easily, like sound from guitar, or even by sweeping the wall/floor join area with a hard brush. It's like there's no wall at all. Very embarrassing in units with toilets on each side of a unit dividing wall. Absolutely should not be used for unit partitioning and even questionable for in-home walls in a family situation as everybody will be disturbed by any noise producing activity until everybody goes to sleep, including things one would not usually think of as noise as watching tv at normal volumes. Perhaps feasible for construction of animal shelters, storerooms and sheds, etc. — Preceding unsigned comment added by 2001:470:36:CFF:50AD:7F4B:226E:2764 (talk) 05:11, 12 May 2014 (UTC) This comment makes no sense since excellent acoustic properties are a key characteristic of the material. Much better sound absorption than standard CMU or many other materials. Perhaps the commenter is confused about what material they were listening through. It has "a high sound reduction for privacy, both from outside noises and from other rooms when used as interior partition walls"   (http://www.cement.org/think-harder-concrete-/homes/building-systems/autoclaved-aerated-concrete)

External links modified
Hello fellow Wikipedians,

I have just modified 2 one external links on Autoclaved aerated concrete. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:
 * Corrected formatting/usage for http://www.hebel.co.nz/about/hebel%20history.php
 * Added tag to http://www.byggnadsvard.se/index.php?option=com_content&view=article&id=459:pionjaerinsatser-i-betongens-barndom-konstruktionsbetongens-historia-1890-1950&catid=45:material&Itemid=84
 * Added archive https://web.archive.org/web/20071030190257/http://www.toolbase.org:80/TechInventory/TechDetails.aspx?ContentDetailID=690&BucketID=6&CategoryID=5 to http://www.toolbase.org/Techinventory/TechDetails.aspx?ContentDetailID=690&BucketID=6&CategoryID=5

When you have finished reviewing my changes, please set the checked parameter below to true or failed to let others know (documentation at ).

Cheers.— InternetArchiveBot  (Report bug) 05:24, 22 October 2016 (UTC)

Seems like advertising more than encyclopedic
Lots of fluff, little proof / few citations.

How lightweight?
5 mentions of density in the article… but no figure cited.
 * The CSR Hebel products are manufactured to a nominal target dry density range of 525kg/m³ to 650kg/m³.
 * Hebel AAC is a lightweight construction material with dry densities ranging from 25 pcf (400 kg/m³) to 44 pcf (700 kg/m³).

Note: (roughly); wood 1500 kg/m³; brick  1900 kg/m³.

MBG02 (talk) 06:11, 5 April 2023 (UTC)

article claims, in successive sections, that the material is both long lasting and has a limited lifespan
This is not an area of expertise for me, but recent evidence in the UK seems to suggest the material is not long-lasting: see https://www.local.gov.uk/topics/housing-and-planning/information-reinforced-autoclaved-aerated-concrete-raac

If there is nuance here, can someone clarify? Maybe it is long-lasting in some specific environments and quick to degrade in others? Or ... has the state of the art in knowledge about this substance changed significantly in the past 10 years? Joebyday (talk) 16:36, 2 June 2023 (UTC)


 * It is the reinforcement (I suppose steel rebar) in RAAC that is failing after 30 years, not the AAC itself.
 * This article would, I think, be improved by addition of statistics comparing the durability and strength of AAC with that of a grade of conventional concrete used for the same building purposes. Chenopodiaceous (talk) 14:26, 11 September 2023 (UTC)

Safety
site needs updated due to unsafe material which may degrade after 30 years causing collapse of buildings 2A00:23C8:1118:5F01:A1F0:6517:FEB0:4D98 (talk) 07:48, 1 September 2023 (UTC)

Correction please?
The sentence containing "calcined gypsum, lime, portland cement, water and aluminum powder", the word is ALUMINIUM, the majority of the world uses ALUMINIUM as the describer for the metal, its alloys and uses say as a powder additive.

92.31.51.0 (talk) 10:31, 1 September 2023 (UTC)

Distinguished from Reinforced?
This section is, I believe, seriously misleading. RAAC is widely used in Europe. The current European standard (Rep BR 445) actually comes from Britain.

I haven't yet managed to find out the significant differences from the way it was implemented in the 1960s. But reading the cautions makes one's hair stand on end. Afaics, they treated it almost like standard reinforced concrete using standard smooth reinforcing rods which didn't cling to the lightweight concrete and only gave any strength by cross bars at the end.

Unfortunately most of the information is in expensive standards and I haven't yet found a cheaper source. If there are any with professional experience, please help. Chris55 (talk) 11:02, 1 September 2023 (UTC)


 * Agreed. A further issue is that the introduction mentions forms of AAC that are highly likely to constitute RAAC:
 * First paragraph: "wall panels, floor and roof panels, cladding (façade) panels and lintels"
 * Second paragraph: exterior and interior walls, firewalls, wet room walls, ... intermediate floors, upper floors, ... opening crossings, beams and pillars"
 * Overall, this article is so poor that it needs a quality warning. AlanS51 (talk) 18:02, 1 September 2023 (UTC)
 * Article needs heavy updating..also, aac keeps humidity more than conventional material and can develop mold unlike is stated in their article 46.11.95.203 (talk) 10:25, 3 September 2023 (UTC)
 * A slight correction on my earlier statement: Rep BR 445 is not a standard, it was a review of the situation in 1990s (final pub 2002). I'm happier with the current state of the section but am still in the dark about whether European panels are showing similar problems to the British buildings. e.g. this advert is quite bullish. Chris55 (talk) 20:22, 3 September 2023 (UTC)

Ontario Science Center
I'm not sure that the closure of the Ontario Science Center is a good fit for this article. While there was indeed an engineering report stating that roof panels needed immediate repair and/or replacement, the public perception in Toronto (where the building is located) and the surrounding areas is that this is more closely tied to political agenda and/or cronyism on the part of the current Premier of Ontario. For example,,,,,

It seems to me like it would be best to leave this out of the article, unless we're also going to include listings of other buildings/facilities that were closed due to requiring replacement of RAAC roofs. 216.168.113.99 (talk) 14:29, 27 June 2024 (UTC)