Meco’Briq: Rammed Earth has Nothing Whatsoever to do with Sheep

Alli Dryer — Tue, 15 Mar 2011 18:18:48 +0000

So I took a brief hiatus to go to Paris, and that is why I missed a week of posting. I am sorry. I needed cheese, wine, macaroons, and croissants in the worst possible way, and as a consequence last week I was unable to focus on materials that cannot be ingested. I hope you understand. Now that I’m back, I’d like to kick things off by telling you about a fantabulous rammed earth building system being developed by, fittingly, a French company: Toulouse-based Meco’concept.

We don’t see many rammed earth buildings in the US (outside of the desert southwest) for many reasons including the idiosyncrasies of building code, but it’s a shame because the construction system produces absurdly beautiful walls and it uses extremely local materials. To build rammed earth walls, start digging up the earth on your site (typically the mineral-rich clay-filled part of the earth, not the leafy decaying organic part) mix it with some cement or cement-like ingredients and maybe throw in some hemp fibers to absorb moisture, then tamp the mixture down in lovely wavy layers within the confines of some formwork. The system doesn’t produce much construction waste (you can reuse formwork, etc) and because so much of the wall comes from the site itself there is less embodied energy used for transporting and manufacturing the material. Also note that what you build out of earth will probably last for a pretty significant amount of time (see Pyramids, Mexico).

Images courtesy Meco’concept

The rammed earth technique has itself been around for millenia, but Meco’concept’s innovation is to take the formwork for rammed earth walls and reduce it down to the size of a building block. They’ve developed a snazzy little hydraulic press that can produce 120 bricks per hour (Meco’concept). Each block gets stamped with lego-like protrusions for ease of stacking (Brownell). If you happen to be in France, you can even rent the machine and go to work using whatever materials you find at hand. While building code in the US tends to purse its lips and peer curiously at rammed earth construction as though it were encountering an unexpected stain on a favorite silk necktie, the Meco’briq blocks can stack up to two stories and could behave similar to CMU (Concrete Masonry Units). Building code tends to assume a half-smile and gaze benevolently at CMU as though it were watching its only son excel at sports, so this new technology could potentially make inroads.

WU XING:

Earth. Hello!

Cited:

Brownell, Blaine. “DIY Earth Bricks.” Architect Magazine – Mind & Matter Blog. 02/24/11. Accessed 03/04/11. URL.

Integrity Block

Alli Dryer — Tue, 26 Jan 2010 21:20:15 +0000

Concrete Masonry Units, also affectionately called “CMU,” provide those fortunate enough to be able to lay hands on them with an easy, fire-resistant, low maintenance, cheap way to throw a wall together in a hurry. All that’s needed is a foundation, the aforementioned CMU, reinforcement, mortar, concrete to fill the voids in the blocks where necessary, and somebody with a strong back to put it all together. Convince your somebody to stack these ingredients evenly in neat rows – and voila! You have a wall. You can even cover up CMU with something else if they look ugly. So where’s the drawback?

According to the Portland Cement Association, “the standard concrete block is a rectangular 8X8X16-inch unit (200X200X400 mm) made mainly of portland cement, gravel, sand, and water. The concrete mixture may also contain ingredients such as air-entraining agents, coloring pigment, and water repellent” (Source: PCA). While cement is in many ways an exquisite material, it is also energy intensive to produce. It’s also subject to price volatility due to fluctuations in demand, although I read somewhere that right now it’s being consumed by humankind in larger quantities than water.*

One solution to the problem of too much cement in one’s concrete walls is to bulk the mixture up with a large quantity of dirt. Rammed earth construction and adobe are two alternatives that use soil composites and recycled rock materials – often from the very site on which the construction occurs (local is good). This construction technique produces absolutely gorgeous, thick, luscious walls with amazing striations running through them. Of course, the look is a bit “unconventional” and this might make it tricky to finance the construction in say, a pseudo-Victorian duplex development. The other problem with this type of construction is that not every Tom Dick or Harriet knows how to do it.

Image copyright Bilsano

Integrity Blockhas attempted to take the convenient aspects of a unitized masonry construction system and combine them with the earth-friendly, dirt-filled characteristics of rammed earth construction. Integrity Block’s building blocks are made out of a super-secret proprietary soil composite that contains pre-consumer recycled content (waste material from mining and quarrying operations). The manufacturing process consumes 40 percent less energy and emits 39 percent less carbon (Source: Edmonds). While the goal is to cut cement out of the formula for the blocks at some future date, right now there is 40% less cement than in traditional CMU (Source: Schwartz).

Image courtesy Integrity Block

So here are some reasons why Integrity Block has all the makings of awesomeness: the super-secret proprietary soil composite is formulated such that blocks come in earthy colors like brown or gray; the blocks come in standard sizes, and they meet typical CMU performance standards and established codes. Anyone (by which I mean almost everyone) who can lay CMU will be able to work with Integrity Block. I can practically smell the LEED credit.

As far as I can tell, Integrity Block distributes its product only in Northern California, in order to keep the old carbon footprint low, but they’re trying to expand production across the United States (Source: Edmonds). Let me know if you’ve used this product and describe the experience, if you’re inclined.

Image courtesy fastcompany.com

WU XING: EARTH

The large quantity of soil that has crept into these blocks make assigning them to the Earth category something of a no-brainer. I wonder how they would perform in a marine environment – I’m picturing a sea-side marsh in Georgia, for example.

*I can’t properly attribute this statement and you may choose to assume that I made it up.

Cited:

“Concrete Masonry Units.” The Portland Cement Association. Accessed 01/29/10. URL.

Edmonds, Molly. “What’s so Special about Integrity Block?” HowStuffWorks.com. Accessed 01/26/10. URL.

Schwartz, Ariel. “10 Green Startups to Watch” FastCompany.com 11/10/09. Accessed 01/26/10. URL.

rammed earth – ARCHITERIALS

Meco’Briq: Rammed Earth has Nothing Whatsoever to do with Sheep

Integrity Block