Concrete’s use as furniture is relatively new. Only a few decades ago, concrete furniture would have been laughable as a concept. But you look at modern houses nowadays and it won’t be at all a surprise to see households sport a stylish new concrete dining table. As a whole, concrete’s versatility as a building material is unquestionable. Concrete has been used as early as 4,000 years ago in older civilizations like Rome and even the Mesopotamian empires. As such, its viability as a building material is time-tested and has been refined over the millennia.
Its use in more intricate details however, such as interior design applications and furniture uses, is fairly new. Its innovation in those aspects of space design started in the early part of the 1900s. Thomas Edison, interestingly enough, is known mostly for his development of the modern-day light bulb, but had a plethora of other groundbreaking innovations, concrete furniture being one of them. He set up the Edison Portland Cement Company which would use different ore mining and milling technologies to create cement mixes suitable for use in house construction and masonry blocks. Some notable furniture that Edison made using concrete was the concrete phonograph cabinet, as well as other proposals for concrete furniture and musical instruments.
The various applications and the sheer versatility of concrete have produced many not-so-conventional uses for the material. Concrete can be used in furniture, yes, but also for sculptures and other artistic media. Centuries of refinement and development resulted in various effective concrete molding and setting methodologies. To really understand the characteristics of the material, let’s take a brief look at the basics of concrete.
Concrete is generally made of two main parts: the cement and the aggregate. The cement, which functions as the main binder or “paste” of concrete, has a consistency, stability, and structural integrity that is dictated by the amount of water that is mixed into it. The basic science behind it is that the cement paste has a very specific chemical reaction with water which causes it to crystallize and harden. When it comes to the water-cement ratio, the lower the amount of water in relation to the cement, the harder the cement. On the other hand, enough water should be added so that the cement is plastic and viscous enough to flow smoothly.
The aggregate, which is qualified as either fine or coarse, are added to supplement the strength and stiffness of concrete. These are made from cleaned and consistently sized particles of rock. Coarser aggregates can be made from up to 1-1/2 inch diameter gravel pieces, and finer aggregates are usually made of smaller sand particles, usually with diameters below ¼ inches.
A third optional component is different admixtures that can be added to concrete slurry. These admixtures can serve different functions, such as change the required setting time for concrete, increase its strength, and even change its appearance and color.
A combination of these different components defines how easily workable concrete is. This knowledge is important to be able to create interesting and structurally sound molds for different concrete furniture.