We discourage using lots of cement because of its adverse environmental impact. However, there are times when it makes sense. For instance, concrete is very useful for making strong bond beams and water resistance structures in rainy climates. Foamed or lightweight concrete such as aircrete has become very popular lately because its lighter weight reduces labor and improves the insulation value. Bricks and blocks are the defacto international building unit, so I did a search for “aircrete blocks” and found the Forterra company in the UK, who is a major supplier of these green building blocks. Their products are profiled below.
Forterra, the maker of Thermalite aircrete bricks and blocks, is one of the largest manufacturers of building products in the UK.
Forterra’s Thermalite aircrete blocks are a cost-effective solution for wall, floor and below-ground constructions. They contain up to 80 per cent recycled content, offer high thermal and sound insulation, good compressive strength, lightness for handling and moisture resistance. Thermalite offers excellent thermal insulation properties inherent to Aircrete, making U-value targets easier to achieve and can help reduce the CO2 emissions during a building’s life.
Benefits of Thermalite aircrete blocks:
-Inherent thermal insulation properties
-80 per cent recycled content
-Can be used in internal and external walls, foundations and beam and block floors
-Make U-value targets easier to achieve
-Improves linear thermal bridging performance at junctions
-BES 6001 Responsible Sourcing certification
Image source: Forterra
Related: aircrete/ foamed lightweight concrete
Cellular lightweight concrete (CLC) is similar to aircrete (AAC) but can be produced at a lower manufacturing capital cost than aircrete and offers more flexibility in terms of the different shapes and densities that can be produced. One company that offers moulds and equipment for the manufacture of CLC is Greentec Construction Technologies (https://greentecct.com/).
Have you ever seen anyone use aircrete in lieu of sand/soil mixture in Earth Bags? I watched a video about a ‘3D Printer-like device that fills Earth Bags with sand, from a Cali Company, and was thinking that kind of system could be very efficient in building an’Earth Bag-Like’ structure. I understand there is an expansion factor, and that could improve efficiency of the process. Just thinking outside of the box, and hoping to find optimal efficiency in this process. Thanks in advance.
I have not seen anyone do this, but I have heard someone propose the possibility before. It does seem feasible and possibly advantageous to do this. I’m sure it would take a fair amount of experimentation and trial to perfect such a system. The 3D printed buildings I have seen seem to use a fast curing foamed product that can be extruded directly on the wall without using a form, so in this case the bag would not be needed.
Thanks for your quick response. Love your websites and content. I’ve thought about what you suggested (without the bag) but am concerned that it will not hold to a desired width, without a form. I’ve thought about using horizontal plank-like forms, but am concerned about the lack of vertical structural strength, unless I use more concrete/ cement in the mixture. Kind of a Catch 22. Any other ideas?
You might check these posts to see how the well the printing seems to work:
https://naturalbuildingblog.siterubix.com/spacecrete-formless-vertical-concrete/
https://naturalbuildingblog.siterubix.com/a-3d-printed-house-for-4000/
Approximatelt how much light are air-crete blocks compared to more conventional blocks / bricks of same size
I’ve missed seeing that
Thank you for your reply
I couldn’t find the exact percentage of difference in weights on their website, but from my experience these types of products are easily at least half the weight of common concrete blocks or bricks.
Buying tested, high quality aircrete blocks might be a safer, better option that trying to make your own aircrete. I know it’s fun to experiment, but please be careful.