As a break from my theme of the architect’s role in the project delivery process I will be starting this miniseries of blog posts entitled “architectural opportunities”. I will be using this to delve a little deeper into the materials and processes we are studying in class. First on the docket is concrete.

Every time we are assigned a new project in studio someone will inevitably decide to experiment with concrete. I’ll admit, it does have many impressive material qualities, but its use is not without its challenges.

To me the most interesting aspect of concrete isn’t the material itself but rather the inverse- the processes and materials that are used to turn a liquid into the world’s most ubiquitous building material. More specifically, I think it could be argued that formwork construction is the most challenging and impressive aspect of this seemingly magical material.

In reading more on the subject I came across an essay called “A Building and Its Double” by Mabel Wilson. This essay describes the sculptureHouseby Rachel Whiteread in London. In this project Whiteread cast the inside of a Victorian house in concrete. (Essay)

This project brings a visual aspect to an idea that we touched on in class- the idea that a concrete building is really “built” three times. Once in the formwork, once in the reinforcement, and finally, in the concrete.

Being that it is clearly critical to the final result I decided to look more into the opportunities, and challenges, presented in formwork construction.

In his book Stuff Matters Mark Middownik says “If you can build the mold [formwork] you can create the structure.” After that all you need is some steel, cement, aggregate, and water and you’ve got your concrete building. However, it’s not quite that easy, or simple.

To achieve the aesthetic qualities specified by the architect, builders must come up with inventive ways to create functional formwork. Since formwork construction is considered means and methods, it is up to the contractor to design and build. Below I have given some examples of the different formwork types and materials that are being used to achieve these architectural goals. A quick note, this type of concrete construction is considered “architectural concrete” meaning that it has a visible finish surface. This distinguishes it from structural concrete such as floor slabs and hidden columns, etc. Structural concrete can have some inventiveness with its formwork, but there are more prescribed, traditional methods to form those portions of the building.

Fabric Formed Concrete

Fabric can be used to create flowing, sensuous forms. The difficulties here are creating secondary formwork to hold the fabric taut and in place and developing a reinforcement system to match the complex geometry.

Church of Light, Osaka Tadao Ando, 1988

Here, metal plates were used to create what architects affectionately call “Ando-crete” distinctive for the way in which the form tie plugs are incorporated.

Traditional Wood Formed and Reinforced Concrete

once the concrete arch has cured it will be entirely in compression and therefore able to stand on its own. However, while curing it must be held in place.

Form Liners

Patterns can be creates in concrete that is traditionally formed with incorporate form liners. This requires a high level of precision from the builders.

(Photos courtesy of Slideshow by Thomas Mills)

Plastic Formwork

One of the main advantages of plastic formwork is that it can be easily reused, meaning less waste. It also allows for nearly seamless finishes.

Foam Formed Concrete

Foam formed concrete is especially useful when the foam can be left behind as built-in insulation, such as in foundation walls.

One more thing that I would like to point out that I found disheartening in doing this basic research is that the builder is almost never given credit in architectural journals and websites. I find it unethical on the part of the architect not to give credit to the builders for making their drawings into reality, they did not achieve these results on their own.