Why we GAVE UP on AIRCRETE & What is Our Plan Now? 

A "failed" experiment is the one not attempted. Thank you for your work.

You guys made a really good effort and your evidence based approach has been invaluable! Thanks again for sharing the process. I think your decision makes perfect sense.

To me it seems the biggest macro factor in your experiments that parallels the decreasing results in quality is the fact that the seasons have changed from warm to cold. Maybe aircrete is just a lot more fickle when it gets cold. And others have pointed out that aircrete by itself is not meant to have a durable surface, nor deal with tensile forces. So for others who are considering aircrete, you'll want to evaluate how it fits into an overall system, and not just how it performs by itself in impact and tensile strength tests. And also re: direct contact with support beam- Any time two different materials come into contact with each other it's good to plan for how they will move differently, and the problems that could cause. With weight bearing aircrete you would probably want to pour a concrete bond beam, or if used for insulation, using a material with some flexibility or elasticity between the aircrete and the solid material.

Thank you for sharing failed experiments along with the early successes. So many videos are just exciting preliminary results with little follow up.

I wouldn't give up on aircrete yet! Regarding the testing of your aircrete block under weights, I feel this is a flaw in understanding the strength of aircrete as the blocks were lacking any reinforcement fabric. You need to use a reinforcement fabric over the surface of aircrete which is what attributes to the strength of the aircrete, as well as the shape of the dome itself, if making a dome structure. The blocks by themselves would undoubtedly crumble due to the porous nature of the material. One simple comparison I can make for this might be to consider a foam poster board. The foam by itself on the back of the board will obviously scratch and puncture easily. With the reinforcement of the poster board with the foam, the entire unit then becomes incredibly strong. That is sort of like how aircrete would work as a structure. You absolutely need the reinforcing fabric to give it its strength.

Batch to batch consistency with aircrete is really hard. Recycled, granulated styrofoam is a great stabilizer. It's free. It keeps EPS out of the landfills, it's bug-proof, and it makes batching your aircrete much easier. You still will have to coat the molded panels with a glass fiber matt. Stucco is a great option for aircrete.

Its tough to start from scratch, I admire you guys and your efforts. Keep up the good work.

Your experiments are a success of what materials not to use in certain circumstances. Thank you so much for you time and effort. One year later and I hope your home is strong and secure with all you need it to be.

one way to make it more consistent with its strength and also to improve thermal resistance is adding styrofoam to your aircrete mixture, a lot more thermal resistance and the strength of it is still very good, the only issue is it'll flake against the elements. you need to wrap it with fibermesh then stucco it or like Stephen Williams stucco+limestone. you can find a bunch of neat videos from Stephen Williams on how he built his work shed with it as well as an arched gardenshed now.

Yes! Now you are on the right path. No more need to be running test samples for weeks and weeks and getting frustrated. Now you can build and be confident of strength, quality, and durability. Aircrete was very frustrating for me also. I just could not figure out why I could not get repeatable quality aircrete. Cracking and powdering are all issues I encountered. And do you think you can just repair aircrete?...not with the powdering. So glad to see you are moving along with other tried and true methods.

I applaud the time and effort you put into your Air-Crete investigation. Glad to see you are moving on. Lessons learned in a controlled environment as opposed to potential consequences down the road.

“I never lose. I either win or learn.” Nelson Mandela But... learning by mistake is a long and expensive process. Thank you for sharing your experience, good or bad. It sure help other to go faster.

Good choice. All the test batches and effort was worth it. You learned valuable information. Thanks for sharing

I just wish you guys all success. I know what it's like to have to make radical course changes during a project. It always hurts. But, life itself is really a grand collection of lessons learned.

Let me start by saying, thank you for the awesome video! We need more of us!! However, I'm not sure I agree with your statement that you've "controlled the condition." You never developed a real consistent process. You changed the formula half a dozen times over no more than two dozen batches. You did not measure temperature of the material or ambient temperature for your cure. and as you mentioned you don't seem to have used the same mixing times. Cement is very sensitive to ambient moister and temperature as it cures; mixing time (adding heat into the cement) can also effect cure times. Add to that the fact that the foam is going to loose structure the longer the cement stays open, means you're definitely going to have inconsistency no matter how well you control. I've made about three batches using the same Domegaia set (the newer Dragon XL version). The discrepancy (I believe as I've observed) is due to the fact that the author of the material built these domes in climates which stay stable, well within the cure range of Portland cement. Your place looks like our. COLD! Which means we're going to have huge fluctuations in temp thought the cure process, making it seem like we're not locking in some other factor. IE Did you start every batch at the same time of day, and where they exposed to the same ambient conditions. A really good control (which I need to do if I'm going to cure in the dead of winter) is to enclose the forms in a temperature controlled enclosure, that could keep a nice consistent 60F (the optimal cure temp for Portland cement). The ASTM compression test, uses a hydraulic press with a pressure gauge to test for compressive loads on cylindrical core sample size. The method you used is excellent when considering whether to use this for a lintel or to span an area (which aircrete is not for), it does not inform much as to how much actual compressive strength is available in the final monolithic structure. Adobe only provides about +300 PSI. CEB provides well over 3000PSI. aircrete falls closer to adobe, but still has more than enough strength (even your worst batch, maybe not the cellulose added one) to build a 10 foot wall that is 12 inches deep (no load). Compressive strength is very different than tensile strength. Though aircrete is brittle, and does not have the same tensile or compressive strengths of concrete, it has a very high compressive to weight ratio, which makes it ideal for small structures such as domes and arches where the nature of the structure itself provides load mitigation, and where you're not exceeding the load limits. You can build very strong arches (especially Catenary arch) and domes with the stuff. Most of the materials (even what you would consider failures) can be used in a dome with re-enforcing fabric, and once you have the scratch coat and the finish on it, despite the lack of tensile strength (increased by the wrapping fabric), you now have a strong monolithic structure. Resistant to wind and weather, with far better insulation factors than any conventional frame house you could build, and in the process building an environmentally friendly and cost effective home. I can certainly understand the time constraint, that is a different story. I'm sleeping in a tent, in the dead of winter, build on our property; and as crazy as I am in loving every minute of it, I certainly can't expect my better half to be able to withstand it. So I think your conclusions on aircrete are possibly driven by other factors and not aircrete itself. The inconsistency is not in the product, it is the way in which we (you and I) are producing it, all of my problems with it so far, have been basically self induced.

A bit of summary for my own brain. 😆 (some of my own thoughts included) - while air Crete is a cool material, and someone else might be able to build a house with it, it wasn’t a good fit in this situation for full-wall construction due to batch consistency, compressive weakness, powdering, and microcracks. - difficulty with overall mix consistency despite increased efforts to control for all possible variables. Inconsistency carries the risk of having some good spots and some bad spots in the same structure and even the same wall. - bubble size, issues with large bubbles despite trying additives and nailing down density/quantity. Same risk as with overall consistency. - micro cracks on the surface even in fiber reinforces mixes indicates a risk of long term surface weakness/ potential spalling. Even with surface bonding cement, if the outer layer is weak it can spall. This risk might be ok for a shed but not for a long term residence. - it’s tendency to powder/give way with light pressure is incompatible with the need for lateral support of the metal posts against twisting and bowing. - erratic/low tensile strength carries the risk of exterior wall panel failure in the case of high wind gusts and other weather impacts.

You were so methodical in your aircrete attempt I thought if anybody could do it you would. The alternative to aircrete that I thought was most promising was using ground up expanded polystyrene packing instead of foam. It comes out very fireproof, fairly strong and good insulation. The biggest advantage is consistency without having to rely on foam. There is a company in Phoenix that makes blocks of this material which stack together like Legos and then concrete is poured through the openings to lock them all together. The walls still have good insulation. Another guy on RU-vid built a garage using ground-up polystyrene and cement mixture for the walls and he even tamped them from the top as he was pouring . He then built a second story on the garage to prove the walls were strong. Supposedly you can get the polystyrene packing from furniture stores etc and save it from ending up in the landfill. But you still have to go to the trouble to grind it up.

Congrats. You all weren't completely deceived by crap on social media. Social media is all about getting viewers...not valid info. It's full of many things that makes people wonder "why aren't all homes built this way". There's always a reason.

Thank you for sharing. Comerciallly, aircrete is cured in a controlled environment and the bubbles are produced by a chemical reaction that can be controlled by recipe. This is the difference between CLC (what you have made) and AAC (commercially made). AAC is cured in a temperature controlled pressurized oven. I’m sure your results can be attributed to the cement moisture exposure prior to curing or temperature/pressure changes with weather. That’s my guess anyway.

Sorry to hear the original plan wasn't working. Thanks for sharing your experience though. That is really good info to know. Looking forward to seeing the rest of the build.

Adding fiberglass might help with strength and structure... I did notice that you had a bunch of bags of quickrete... that may affect your batch consistency once you bring the bags home and let them sit outside they can lose quality fast

Sorry for your frustrations! I just came across this video and I am WAY late to the party. Haven’t read the comments from others. Just wanted to offer some information I learned some years ago when I was sold on rammed earth: it’s a method called PISE which is the acronym for “pneumatically impacted stabilized earth.” The system utilizes sheet goods (kind of needs to be plywood) as an inside-of-wall form against which is shot resident soil mixed with Portland cement and fiberglass shards and applied with a gunnite machine which introduced water at the nozzle. I saw a residence and a winery office building done this way in Northern California and it actually passed building code with the addition of some rebar which the builder told me was totally unnecessary, but required here in earthquake country.

Thank you so much! The videos and experiments you made will be of great service and value to many others, so please don't feel your work has been a waste. And if i might ask- many of us would be interested to see an update on the garden wall in the spring or in a year. (And if you have space to keep the samples, maybe evaluate them once they've all had a chance to fully cure and age a bit. I have a feeling a few of them might behave differently after several months)

Aircrete is meant to be built with self reinforcing geometries like domes and arches, just like Roman concrete, then encapsulated on both sides with fiberglass or basalt mesh. When it is kept under compression and encapsulated with these tensile layers it is strong enough to even be earth buried. Straight walls are not recommended. Good luck with your build.

I understand that adding ground up Styrofoam makes aircrete stronger, more insulating, and easier to work with.

You guys gave it such a good shot and I am sorry it didn't work out. I look forward to seeing how the new house goes!

I wouldn't use it for load bearing, but as an alternative insulation it would probably work well.

Thanks for sharing your experiences, even if they didn't turn out the way you hoped.

Aircrete is not good for load bearing unless the bricks are at least 12" ×12"×18". The best way to use it is within structural panels to serve as insulation. That's what seems to work the best. It can be used for domes because that shape is "self supporting".

It sucks to invest time and money in a building system only to have to abandon it. Hopefully your experience will spare others from that experience. Thanks for sharing!

I can tell you exactly what you did wrong as far as the consistency of the aircrete is concerned. This is a mistake many make including me,very frustrating, so don't feel alone. Ignorance is NOT stupidity. The first time you start making aircrete there is a hesentincy to the mixing. As you do more, you naturally mix faster. To keep the small tight bubbles, foam size, it is extremely important that you mix at a very slow rate. Moving up and down, side to side. Never allowing the whirlpool effect to carry air into the mix. Mixing to fast also causes the foam to combine into larger bubbles and when taken to extreme the air crete will collapse during the curing. This is obvious when I watched this video and saw how the progression of the old to new bricks where laid out. #2 The plans for your house are for the most part conventional. Aircrete in this case is only good as an insulator, not a structure. So you made the correct call changing your plans. Beyond what I have to say you guys presented a awesome video of your experiences and I learned from it. Thank you so much for posting!

This was extremely helpful! Thanks for sharing. Glad RU-vid recommended. I won’t bother sourcing the materials. THANK YOU!

I think it would be well worth your while to attend an aircrete workshop. I know both 'Aircrete Harry' and 'Domegaia' put these on. Harry also does consulting work at a very reasonable price. If you watch his videos, you'll see he went through all your issues and he has shown how he overcame them.

Thanks for that useful vid. That will help a lot of people. Not everyone would show a failure.

Perhaps aircrete is more suitable as an insulation material and not rely on structural capability at all. It looks like your cement dried out too quickly, thats why the blocks are powdery, cement needs moisture for a few days to chemically cure.

Most intriguing, I’ve made a hundred honey bee boxes from aircrete but mixed with sheep wool for humidity regulation, but this was done by a pro with my moulds and I finished them of with micro cement

Red and April thank you for sharing your "real" journey. By you sharing your data and your outcomes (good and bad) is like learning right alongside you. --So, as you have proven, Aircrete created with "foam" (foamcrete as I call it) is very fragile. It has its use in certain geodesic forms or non-domiciled structures, and hardfacing helps stability some (Honey Do Carpenter/The Happy Heresiarch) - but you really need chemically generated air bubbles for consistency and autoclaving to make aircrete somewhat durable. (Autoclaved Aerated Concrete = AAC - Think Hebel or Aercon AAC Blocks) But DIY'ing AAC is prohibitively expensive - as autoclaves are. And purchasing AAC is also expensive and defeats the goal of self-sufficiency, IMHO. You folks seem as if you've done your research, so I assume you know how extremely labor-intensive rammed earth really is. --So my question to you is before you move on to rammed earth, had you considered these two alternatives? --1) Creating polystyrene/cement blocks or panels instead of foamcrete? You may be able to create more durable blocks/panels for the walls in your home, that perform just as good - if not better than aircrete, simply by using recycled ground-up polystyrene beads and Portland cement with an ad-mix. (Think "The Perfect Block" out of Tucson - but without holes or need for the expensive grouting) Structural support would still come from your steel frame. Stephen Williams (Aircrete) - has a RU-vid channel where he's built a structure in this manner. --2) If you like the thought of truly using "earth" as the building material, had you considered compressed earth block for your home? It's still labor intensive but less so than rammed earth and it produces similar look/performance of rammed earth. "Sustainable Living" RU-vid Channel

As someone whose only experience with air crete is “I watched a few videos,” I would just add that some claim to get better results with foam crete, using a soap-based foaming agent to “fluff” the mix. I should add these videos were made by people who were promoting/selling the idea of foam Crete, so of course they may not be the most unbiased source, but a suggestion if still considering. I applaud you for trying this build, and doing so very reasonably and methodically.

Graphene-enhanced concrete is tested and it provides a 146% increase in compressive strength, a 70% increase in flexural strength, and a 400% decrease in permeability. The incorporation of graphene in concrete would develop structures with increased durability, an increased conductivity, and thermal properties. Resulting in an overall decrease in CO2 emissions. Hemp concrete or hemp lime, it's a biocomposite made from a mix of the woody core of the hemp plant, lime binder, and water. The hemp core (also hemp hurd or shiv) has a high silica content that allows it to strongly bind with the lime.. As a result, you get a lightweight, cementitious material with good high insulation properties that weighs six to eight times less than concrete. It's ability to aborb CO2 emissions actually make it a carbon negative product. Because of the high moisture content care must be taken in the drying or curing of hemp, unless your intention is to make hemp graphene. At this time hemp is available in moderate amounts except for industrial or textile use and is utilized in a variety of products from clothing and shoes to bulletproof vests, car parts, artesian niche soaps, oils, beauty and health products. For hundreds of years it has been available as rope for maritime travel in boats and netting. Hemp as a means of paper and due to it's strength even the paper is utilzed to make implements, dishes, cups and musical instruments. Aircrete is simply concrete with bubbles., there is no set formula. Fine foam, which has a high density, can be added to increase aerated concrete's strength, which results in a stronger aircrete. When high densities of foam are included, aircrete can become brittle, and chipping can occur. This type of aircrete will have limited compressive strength and could not be load-bearing.Aircrete offers many traditional concrete benefits with added properties to enhance sustainable and energy-efficient homes. Aircrete offers superior insulation properties due to foam and air bubbles built into concrete itself which can be enhanced by adding various types of polystyrene or polyurethane foams improving it's insulation values.Aircrete is most often used for exterior and interior walls. However, aircrete can also be used for several other home applications, such as precast blocks and panels and concrete slabs for an insulated flooring system. In some cases aircrete is used for poured roofs, increasing insulation capacity of ceilings and attics where heat tends to escape from homes. When used with additives it's load bearing capabiities, compressive strength, durabilities and other characteristics are greatly enhanced.

Thanks for documenting this so others will know to not rely on aircrete as structural elements. This is why others use more structurally sound elements within or around the aircrete to compensate. Personally I think such compensations make aircrete a superior solution but your pivot worked well. Well done.

Thank you for showing the reality of aircrete. I commented in your other video that I used perlite, it is rock bubbles so there is no inconsistency in the air bubbles because they are already bubbles incased in rock when you get the perlite. I also sandwiched the lightweight concrete with fiber stucco to give it hard surface. Where are you located that you can do builds like this? Rural Texas? I will also say if you are willing to spend lots and lots of time building, they are many options. My idea was a method that is not labor intensive, but only time intensive using forms to create arches. You can only pour one arch at a time, and then wait days for it to harden enough to do the next one, and 50 arches then takes a long time....but not a lot of labor, and it would scale if you have multiple forms.

I worked for a roof and roof deck company back in the 90's. We used "light gage metal cee's" to make trusses for schools, Structural Engineer designed and all that. However, these weren't the 24 or 26 gage cees used for interior, non load bearing walls. These were up to 10 gage, mostly 12-16 gage.

Temperature's surely could be a factor. Maybe in a stable environment, same temps, etc the results would be the same. Thanks for sharing the information.

You folks are an inspiration. I have been testing mixes of portand cement and native soil here. I have found a 3/1 mix of screened soil is really good stuff here. Thanks!

At about the start of September 2023 approximately 174 schools and other buildings in the U.K. have had to be closed by the government because of crumbling reinforced autoclaved aerated concrete (Raac). Cheaper isn’t always better especially when safety is concerned. That material was predominantly used between the 1950s - 1990s with a 30 year shelf life.

100% agree with your conclusion, heat and cold cycles would have caused cracks and separation.

Add graphene and styrofoam for the perfect building material. Graphene's made with graphite and milk mixed in a blender for ~30 min. It can increase concrete strength 8 fold.

It is because you are expecting it for application that it does not designed to. The aircrete is designed only for low-height one-floor-only mini house with reinforced fiberglass mesh after finished placing it. It is not designed to be used for supporting heavy weight and it is known to have very fragile tensile strength. It is suitable for short wall with very little load. The good thing is that you can add more thickness without problem and will provide more insulating power significantly. This is good for those looking for insulating + wall all in one.

How long have you had that cement powder? It has a shelf life. After three or so months it is starting to absorb enough moisture from the environment to significantly affect its strength. Obviously that number is affected by how well it is stored and the humidity in the area, but as a rule of thumb...

As a residential designer that specifies the materials on house and addition projects I hear from customers interested in all sorts of building systems. A lot of folks lock onto a particular system as the answer for their dream home and I always need to ask what the question is that material answers. It's really easy for people to get caught up on the miracle system that does it all but the choice needs to be based on the sum of a bunch of questions. What is the local climate and what are the site risks, what is the ability of the client to pay, what kind of materials are locally available and meet the clients desires and finances, what are the local trades capable of doing with proven competence are a few of the issues, and there are a bunch of other questions that need to be answered. I have never gotten to build in the desert but if somebody offered me a project on a big lot in an arid place I'd start by looking at what the locals have been doing for the last thousand or so years. If you want low carbon and low embodied energy you're going to minimize concrete, styrofoam and steel. If longevity, healthfulness and sustainability are important then start thinking adobe or rammed earth at a site like this. Wood is good.

Was it by any chance cooler and more humid with those successful tests? I learned if any concrete dries too fast, it cracks and crumbles...or was the heat and humidity the same during pours? I know you've moved on, but would love to know if it's worth it to invest in a hopper that measures those variables in it's mixture ratios so the batches all come out the same. Super important when needing to make a consistent mortar, too, so the walls don't crumble later if they cure at different rates and contract/collapse. Thanks so much for sharing your efforts!

I've done some testing myself and your foam concrete looks like is doesn't use enough sand. What I've done to make it more durable and reduce big air bubbles was to increase the tenside amount and foam it to 30g a litre. I also increased the amount of sand but used very small construction sand. I also added hemp fibres to it. The resulting bricks behave like hard plastic. The denser foam can hold the smaller sand much better and hemp fibres gave extra support. If you need tensile strength you need to add a large mesh structure of some kind, small shredded fibres dont help much and can even make it more brittle. You need long intertwined organic fibres or a glassfibre/metal mesh or similar. If you want to cheap out and have an easier build I'd use earthbags instead of foamconcrete. Foamconcrete is hard to make and needs exp. or one needs to follow a recipe exactly for it to be good.

Coat the aircrete surface with brushable plaster/Paint slurry: Mix up a bit of white cement, water and sodium silicate (2% by weight), Highly reflective (High SRI) and very durable.

Hi in Jamaica we use a constant mix of 3sand 1cement 3gravel plus use 3/8 rebar Plus you can add starofom flakes for insulation

We have urban/ wild land interface fire codes here so any new construction or window replacement needs to comply. At least one tempered glass pane in an insulated glass panel. Easy to order from major window and door manufacturers. Siding can be stucco, cement board or metal. Try to skip the rigid foam since it is extremely flammable. Rock wool is expensive but fireproof.

The first section of wall, that went well for you, was where you tossed in all the old aircrete you'd used for testing. Perhaps it acted like aggregate to add some stability.

It’s very exciting that you can finally move forward! Learning from experiences is never a fail. It’s going to be awesome! Love that snake. 🥰❤️👌🏽

Hi I really appreciate your efforts in building your homestead. What I didn’t notice in the whole video while dealing with all these different mixtures is a vibrating tool to remove bubbles and settle the different “cretes” you’re using. Have you tried any types of tools like that to help with your mixes? Great luck in your endeavors I hope to one day build my own home. May God keep you in His Mighty Hands✨💫💎

The problem is entrainment... you would have to have all the material in a building so it was away from the wind the wind blows away the cement... and then you would have to weigh or precisely measure the materials and use a machine that does the mixing, first dry and then wet... then you would dial in your process with the mixing machine, and dfi your tests, you would arrive at a uniform process if you could control temperature of air and water and and the exact time and speed of mixing... also fibers and probably additives to be considered too... maybe even a different gas than just air, maybe co2 or idk...

Can recommend solid concrete blocks. Readily available. Doesn't take too long to get good at laying them. Just one man can make a house. Indestructable cheap and Fast. External cladding thermal insulation gives fantastic performance. No formwork.

I am no architect but I have worked construction for quite a few years on your c Channel trusses you should be fine just using them as is look up how much load it can actually Handle by the thickness of it and how long it is another thing to think about is you should put wood purlins on it so you can attach the metal sheeting you also want to put a vapor barrier between the metal in the wood to keep down wrought and good way to attach the wood to your c channel is a Ramset make sure you get the right 27 caliber charge but this will be quicker than using screws because you literally just push it up against the wood and pull the trigger screws will burn out and drill bits will burn up it's a very cost-effective way to attach wood to metal but make sure you only use this against heavy metal not the sheathing it will just blow a hole through the sheathing

I've been watching DIY aircrete videos for a few years now and the inconsistency has always seemed like a potentially very serious problem. Your channel is the first I've seen that discusses the inconsistency of DIY aircrete batches. Unfortunately, I suspect that the only way to produce viable aircrete is with commercial production methods that use exothermic chemical reactions, like combining calcium carbonate and aluminum powder to produce hydrogen gas (rather than adding soap bubbles), and then kiln drying, which maintains the integrity of the aircrete.

Hi: 1.Can you tell me what counties in AZ allow you to opt-out of some inspections? 2. Are you aware of any other USA alternative building friendly areas? 3. RE aircrete : Some water sources, due to minerials, are not aircrete friendly. Old bagged cement can also cause problems. IF you wanted to give it another try: A. get some fresh cement ( maybe even another brand, maybe even from a different source ) B. Get some water machine water ( this will have no minerials in it ) . use this water for foam and to mix with cement. I know this can be 30 to 50 cents a gallon; no problem, there are ways to fix your well water if minerials are the problem. C. Lastly, you may need to protect your tests from the cold. If you can answer 1. and 2. that would be great you can skip 3. if you wish. Thanks, Tami

If I were making a tiny retirement house in the high desert, I'd just go with cinder block. For coolness, I'd make an extra-high ceiling and tile floor. Can always cover it with a rug in the winter. Two stories might be best: appliances and summer sleeping downstairs, winter bedroom upstairs. But then as you get older, you won't want stairs. Anyway best of luck.

Portland cement in concrete is a binder for the aggregate. The strength of the concrete comes from the aggregate not the cement binder.

you are looking for: Polystyrene construction foam blocks fireproof, insulating, light, easy to build with

It had occasion to talk with the folks that have been making it commercially for 50 years in Europe when they tried to move into U.S.markets. There were two key things that they did. #1was that they mixed aluminum powder that slowly gave off tiny bubbles as it reacted, so it poured into molds without bubbles and then rose like baking a cake. Then once it roseto the desired amount the mold was heated to speed and finish the chemistry that gives concrete its strength. I still have the sample in I use as a trivia on the stove. It never gets hard against abrasion like regular concrete ( being able to cut it with a handsaw is considered a feature) an will always need protection from abrasion, but it does not fall apart like your sample. As I suspect that the change in quality might have been due to temperature as much as anything else (and the original invention was in Sweden) that would be a good reason to run steam along the outside of the mold.

Considering the climate which looks hot and dry in summer and cold in winter I would have leaned towards digging into earth and using the displaced dirt as a building material. Do an earthen covered home in part.

The test blocks seemed to fracture about the same distance to the proportion. Perhaps resorting to a more common brick size would eliminate the fracturing and lay them like bricks. Hat's off to you guys, I'm a contractor in Houston and all that is labor intensive.

You could do a section of traditional concrete around your beams And i would definitely use traditional concrete for the base footer

I applaud you all for taking on building your own home. Seems to me you took on a course in materials science and engineering, without having an instructor to help you know the chemistry and physics principles in play to explain what you experienced and figure out how to make changes to get what you want. I agree with commenters who made a point about the environmental changes (due to weather) that impacted your results with the aircrete blocks. There are chemistry and physics principles at play that commercial operations tightly control so they get consistency in production variables. Your experiments show how sensitive materials can be to the environment. I wish you well with your new approach and hope the result is all you want it to be!

Did you try using Perlite instead of foam? It makes perlitecrete, much more consistent properties.

What you should use is shredded styrofoam mixed with fiberglass reinforced concrete. Much easier to get a good mix. Problem with aircrete is air bubbles collapse resulting in a poor mix

try adding in dry lime into a wet mix, in decent chunks too, nothing bigger than a pinky nail diameter but not powder. It should help fill voids and cracks as it sets. reducing the problems you're facing. the romans also did this we now know

Super helpful to know! Thanks so much for the warning!

Really appreciate this video.

If were use the pole barn method you could use the aircrete between the 6x6 post and you would not have to worry about loads and from what i understand you need to weigh the foam to get consistent results.

A couple of important tips The ground must be compacted properly. And if the ground is to soft you will need to build a spread footing. Having a proper concrete footing is a must. Next .. if you want aircrete to work here . .you would have been better off to fabricate it into blocks. Temperature & water content is important The other thing you haven't factored in is rebar aka re -enforcing .Spending the time to research the applications & methods is key. To avoid much unnecessary labour and heart ache. 🙂🙏

Have you tried long string hay mixed with aircrete? Fyi air Crete can only be used for non structural areas.

How many days did you let these test blocks cure before you tested them? Concrete gets stronger after 20-30 days

I am someone who is a fan of the Foam core fiberglass construction process. Therefore I would have incorporated foam insulation in the construction. Aircreete looks good but the problem is that it looses 90% of the structural properties of concrete.

I’d go slipform big rocks stone masonry in rammed earth. You don’t need to use cement in rammed earth. Just make sure you use a lot of big fist sized rocks and use as much clay as you’d use for cob with concrete aka sharp sand and lots of gravel from different sizes up to plenty of of softball sized rocks

I'm planning to build a house with AAC (Autoclaved Aerated Concrete) from Hebel USA. It's like Aircrete but it's cooked in the oven at the factory, with accurate sizes ( most common block is 8"X8"x24"). Highest compressive strength is AAC-6 ( that is 6 N/mm2, or 870 psi), can build up to six story high). You could have taken this path, but a bit more expensive.

So , have you ever changed the formula? I just watched it on RU-vid, they use very small amounts of cement. They produce it with a large amount of lime and much thicker than this.

I appreciate Tiny Giant Lifestyle YT channel on aircrete, as he demonstrates that micro-cracks are a non-issue if you apply reinforcing mesh on both sides, and this also eliminates the strength concerns. If you have a rigid frame and are using aircrete to fill in the blanks, how much stronger than rigid foam does it really need to be?

F aircrete 😂, lol, j/k, but the hell I seen y'all went through with that aircrete was just crazy. Y'all did so much work and did some awesome testing that helps everyone else who might have gone down that rabbit hole, I had seen some videos on it and immediately thought man. That's a great idea! You could just pour for thick walls and have super insulation and it would be strong and amazing but I guess the strong point doesn't work. Thing will just crumble like packed together. Sand, lol. Anyway, I guess if aircrete is a dead end, I may look into one of those printed houses where they printed out of special kind of concrete and it prints avoid in the wall so you can fill it up with insulation. Insulation anyway, good luck to y'all. Keep up the great work

Temperature/ humidity was probably the factors. Years ago we contemplated alternative building methods. We tried earth bags. Very labor intensive. What we discovered is that unless you have a lot of free or inexpensive labor, alternative building methods take lots of time. As they say, time is money and money is time . Weather is a big factor when building off-grid. You often need shelter sooner then later. Instead of aircrete, years ago I found some builders who were using pumice crete. Light weight, insulative and fire proof. Not sure on the strength.

I spent a lot of effort on aircrete garden boxes. The finish product was so brittle that I completely gave up. Going to poured concrete.

Weigh out the foam and use portland cement. If you use exact proportions and math it out it will be consistent every single time.

I have a earthbag hybrid. Outside I used concrete, inside I used plaster. You can't drive a truck through it ! The only place I used aircrete was the roof, (steel reinforced ) but only with additional "Paint Crete" to seal tge aircrete and then a speaker on top of that. Worked great. Look for a page called "Flying concrete" for use of ferro cement. You may like that alternative. I have also used burlap impregnated with Portland cement ! Paper Crete was a good mix for interior.

Nice to get more info on this subject.

Sorry to hear you weren't able to make it work for you. I don't if you have seen the 'Honey Do Carpenter' channel? He does almost everything Aircrete. Don't know if his formula or method is different.

Really enlightening, sure appreciate you hard work.

Thank you for sharing this valuable work. you have saved me from tons of work and money.

I'm going with cinder blocks. Not sure how I'll dress the exterior, but I have time to figure it out.

I'm totally new on this channel and this is my first video so my. Question is: why not buy aircrete blocks? With all the time and materials spent on trying to diy it, I think buying pre-made aircrete blocks would have been a better choice. Also aircrete is not like cinder blocks, they are not meant to be in contact with (possibly) wet surfaces. Like compacted soil. It should be on a concrete foundation, and to block any wetness you need to seal the concrete underneath the walls with a tar like foil you heat up to make it stick to the concrete. And it has to be covered both on the outside and inside (ie. drywall or wood etc.)

Keep it simple the support and strength comes from fiberglass wrap over aircrete

That's a lot of hard work folks but hope you get some good fruit for your labors in the future.

An honest reporting of the results. All I can say is keep trying , and maybe you stumble upon the results you want. The cost have to be a factor also. I thought the idea was to have as many bubbles as possible, as it would increase the R value. More lime research self healing concrete. That is what the romans had.