Design Considerations

(Updated 11/01/2013)

I sometimes am asked how I go about the process of design. What I like to achieve, though don't always manage to, is a sense of elegant simplicity, a sense that the design is as simple as possible, but no simpler (as discussed in Ockham's Razor below). It is an often elusive quest because achieving elegant simplicity is more demanding than simply achieving complexity.

As I consider a new design I contemplate a long list of questions: "How important is the perceived need that this design is addressing? Is it really a need? If so, what is the simplest way in which it can be met? What are the trade-offs between simplicity of design and convenience of use? Does the form of a design reflect its function in an aesthetically pleasing way? Does the design address the need in ways that tend to make my life more free or more encumbered? More integrated with the local environment or less so? What is the environmental and economic and social justice impact of the materials used? Is this design versatile--can it serve multiple purposes? Is it simple enough to be easily replicated?

Since many simple technologies are not available "off the shelf", they are often constructed by the user, so ease of replication is an important consideration. Whether a design utilizes materials that are native, scrounged or purchased new, the easier those materials are to obtain and to work with, the more likely the design is to be replicated. Easily replicated designs will inspire others to use them and when the time comes to repair or replace a particular technology, it will be simpler to do so.

Another aspect that is indispensable to the design process is a commitment to use a design on a daily basis for extended periods of time. For example, at Casa Juliana in the early 1990's, after visiting several appropriate technology centers in which many of the technologies were in disrepair or disuse, we decided as a community to commit to two rules that would apply to all the technologies we designed. The first was that we would only design and build technologies that we intended to integrate into our daily lives. The second was that we would strive to make those technologies work 100 percent of the time. That is, if an existing technology needed redesign or repair, that was given a higher priority than pursuing a new technology.

This commitment to consistent use resulted in input from community members that proved indispensable in facilitating improvements in the simplicity, function, aesthetics, ease of maintenance, etc. of all the simple technologies we developed.

Simplicity vs. Complexity

When comparing technologies that perform the same function, a technology that is simpler in design will tend to be simpler to construct and repair, but will tend to require greater skill to use, whereas a technology that requires less skill to use will tend to be more complex in design and more complex to construct and repair. For example, a straight razor is relatively simple in design and construction, but requires considerable skill to use, whereas an electric razor is relatively complex in design and construction but requires little skill to use.

Another example is seen in the various toilet designs featured on the composting toilet page. The toilets that are most convenient to use are also the most complex in design: their construction involves fairly specific dimensions, screening details, etc., and requires several days to a week or more to complete. In contrast is the simple bucket toilet which can be put together relatively quickly by almost anyone, but using it involves frequent emptying of buckets which requires some skill and attention to detail.

There is a cultural bias in the U.S. towards convenience of use in spite of the accompanying increase in complexity of design and difficulty of construction. I've often observed this bias, even among those desiring to go "sustainable," whether in regard to composting toilet designs, gray water systems, house designs, etc. In our experience, challenging that bias and instead focusing on developing simple solutions to daily living needs and learning the skills required to use them well have moved us towards a greater sense of self-sufficiency, freedom and satisfaction.

Ockham's Razor as Applied to Technology

William of Ockham, a 14th century Franciscan theologian and logician, is noted for an adage known as "Ockham's Razor" that has enjoyed various iterations through the centuries. Einstein's version is appropriately succinct: "Make your theories as simple as possible, but no simpler." Although his version applies to physical theory, it has a corollary applicable to technology as well: "Make your technology as simple as possible, but no simpler." During many years of designing, building and using a variety of such technologies, I've repeatedly observed the applicability of this corollary.

For example, some years ago we acquired a few 55 gallon drums which we decided to use as outdoor food storage containers. One design challenge was to devise a lid for the barrels that would keep out elements and animals. After some thought, I decided to use a square piece of sheet metal, bent to form a simple lid.


Pantry barrel lid


The lids worked well and we were satisfied that the requirements of Ockham's dictum had been met. One evening some months later however, we heard a rattling outside and peering out the window, saw a raccoon entering one of the barrels. Obviously, the technology was too simple to be effective. I then devised a simple and convenient system for securely fastening the lids. This proved to be raccoon proof and we were again convinced that Ockham was satisfied.

Pantry barrel lid with hold-down ropes


Then, several months later, we had a heavy thunderstorm after which we discovered standing water in the bottom of each barrel. Subsequent experiments with a watering can revealed that water drops were being carried under the lid and then dripping into the barrel. After further thought, I decided to apply a bead of caulk to the underside of the edge of each lid. This acted as a "drip edge", causing raindrops to fall to the ground outside the barrels.


Pantry barrel lid drip edge


That was some years ago and the lids have since performed without problems, having finally achieved the correct balance between simplicity and complexity to satisfy Ockham's dictum. This is not an isolated instance, but rather is just one of many examples of the process of observing problems, devising solutions, implementing those solutions and observing the results, all in an effort to "make the technology as simple as possible, but no simpler".

2013 Update:

The food storage barrels described above have clearly satisfied Ockham's dictum.  Now in their 15th year of use, they continue to serve as our primary food storage system without any further modifications. 

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