Biomimicry & Sustainable Architecture/Design/Building

Biomimicry is a rapidly developing discipline in design that draws inspiration from the startling structures that natural organisms have evolved over the course of the last 3.6 billion years.

Proponents of biomimicry contend that many solutions exist within nature that we can employ to radically transform our construction techniques in order to build super-efficient structures, high strength bio-degradable composites, self-cleaning surfaces, zero waste systems, low energy means of creating fresh water and much more.

Biomimicry (also referred to as ‘biomimetics’) is distinct from biomorphic design, which essential seeks to copy or allude to natural forms and shapes for symbolic effect. Biomimicry is a functional discipline. It involves studying the way that forms deliver function in biology and then translating that understanding into design solutions that suit human needs.

Biomimicry offers completely new ways of approaching design such that the whole system can be optimized and radical increases in resource-efficiency can be achieved.

Typically, human-made systems and products involve using resources in linear ways. Often the resources are derived in highly energy intensive ways, then used inefficiently and partially ending up as waste. While some benefits can be derived by looking at each of these stages separately, it is worth remembering Einstein’s maxim: that problems are not solved by thinking within the same level of consciousness that created them. Biomimicry offers completely new ways of approaching design, such that the whole system can be optimized and radical increases in resource-efficiency can be achieved.

If future generations are to enjoy a reasonable quality of life then we urgently need to redesign our buildings, products and systems to be completely ‘closed loop’ and to operate with current solar income. While no one suggests that these transformations will be easy, biomimicry offers a vast and largely untapped well of solutions to such problems. There are countless examples of plants and animals that have evolved in response to resource-constrained environments, and a lot can be gained by treating nature as mentor when addressing our own challenges

The biomimetic office building

The Biomimetic Office is an example of how biomimicry can be applied to the radical rethinking of a conventional building type. The client entrusted the architects to assemble a team of excellent consultants which included a globally renowned professor of biomimetics. The client also accepted the proposal that to achieve the best results a new approach would be required as follows:

1. The team should do a concept study first with a minimum of constraints (no specific site or budget at the start)
2. The second stage should be a commercial feasibility study that refined the concept proposals to suit a target budget identified by market research as realistic for a high-performance building
3. A truly collaborative process which requires a certain amount of ego suppression on the part of the architect

The selection of polymaths as part of the team resulted in a very rich dialogue in which the boundaries between disciplines dissolved and several ideas emerged, some that the individuals had been nurturing for many years but had never had an opportunity to implement. The team set out to design an office that would be radically more resource efficient in terms of its energy and material usage, that aimed to achieve a minimum 10% improvement in the productivity of its occupants, to generate more energy than it consumes and for the air coming out to be cleaner than the air going in. It was clear that some of these objectives went beyond sustainable design to strive for restorative aims. The first workshop concluded that daylight was likely to be the most important driver of strategic form for the building. Light is a pre-condition for most life on the planet so it’s not surprising that there are numerous examples of organisms that gather light in intriguing ways:

The spookfish, for example, has amazing mirror structures within their eyes which point downwards to focus lowlevel bio-luminescence into an image on the retina.

The stone plant, a succulent native to desert climates, was another example. The majority of the plant structure grows below ground for reasons of thermal stabilization, and it has what could be called a ‘skylight,’ which brings the light down into the plant to where the photosynthetic matter is.

Brittle stars, such as Ophiocoma wendtii, are a type of starfish that have a covering of calcite crystals which function as effective armour, as well as near-optically-perfect lenses. These crystals focus light onto receptors below so that the whole body works like a compound eye. Additionally, brittle stars can control the amount of light coming in by means of chromatophores (pigment-filled cells) and adaptively tune the focusing of the lenses.

It is often organisms that live in the lowest light conditions that demonstrate some of the most interesting adaptations, which can provide inspiration for architecture. The rainforest plant Anthurium warocqueanum has evolved a covering of cells whose diameter, shape and spatial layout create lenses over its leaf surfaces. This surface appears to be able to concentrate diffuse light onto a group of chloroplasts aligned at the point of highest concentration. This strategy ameliorates the basic disadvantage of its growth habit: receiving no direct light because it lives near the forest floor, under the shadow of dense canopy above.

With these examples, the team was encouraged to design more creatively with daylight in mind, and the building was designed to ensure that every inhabitable part of the office floor was within 6 meters of a window.

Anthurium, the forest floor dweller, sparked the idea of rooftop lenses that could concentrate diffuse light into fibre optic tubes so that daylight could be conducted around the building to where it was needed. There are some similar products on the market today, but they all depend on focusing on parallel rays of direct sunlight, which is less appealing when there is direct sunlight because general illuminance levels are higher, and getting light into the building is less of a problem. Anthurium inspired the interesting prospect of gathering light in diffuse conditions, and the idea is now progressing as an independent research project.

Biomimicry offers enormous potential to transform our buildings, products and systems.

The idea of incorporating a symmetrical pair of large-scale mirrors in the atrium to reflect light into the ground and first floor levels was borrowed from the spookfish. Additionally, the space under the mirrors was well suited for the creation of a dramatic auditorium – a feature that would add value to the building.

Another added value of abundant daylight in a designed space is the a range of plants that can be grown in the office space. NASA has carried out extensive research into creating self-sustaining internal environments, and found that in sufficient quantities, three plants – the Areca palm, the Mother-in-law’s tongue and the Money plant – can process and neutralize all the contaminants in a normal internal environment.

Areca palms produce oxygen during the day; Mother-in-law’s tongue produces oxygen at night; and the Money plant removes formaldehydes and Volatile Organic Compounds (VOCs). This was tested in a 5,000 sqm office building in Delhi and resulted in a 52% reduction in eye complaints, a 24% reduction in headaches, and more than a 20% increase in productivity. The team plans to do the same in the biomimetic office building which should help towards the aims of boosting human productivity and wellbeing.

The strategic design of the structure was led by optimization of daylight use and biomimetic techniques used to refine the structure that minimized the amount of material required. Professor Julian Vincent has characterized natural structures by saying, “In biology, materials are expensive and shape is cheap”. To express this in another way, biological structures often achieve their resource efficiency through complexity of form, evolving to place the material exactly where it works most effectively. A bird skull demonstrates this principle in the way that very thin layers of bony material are laid down and connected with tiny struts, not dissimilar to dome or spaceframe architecture. Another interesting example is the cuttlebone, which is also made up of thin layers of bone connected with undulating walls. Both the bird skull and the cuttlebone achieve strength through complexity and use a minimum of materials to their maximum effect.

The team analyzed a standard type of building construction – a floor and column structure – in terms of its structural efficiency and found that a lot of that material in the middle of the columns and the middle of the floors could be removed. Following the shapes dictated by the present forces suggested that the columns should be hollow, and the floors deeper in the middle. Excess mass from the floors could be removed with void formers of varying size. This could be achieved with relatively minor adaptations to established technologies such as ‘bubble-deck’ and fabric formwork. The resulting design approached the kind of efficiency present in the two biological examples.

Developments in 3D printing offer the potential to get even closer to the efficiency seen in biology because there is
no cost penalty to complexity in additive forms of manufacturing. This example of structural optimization captures how useful biomimicry can be as a tool. Through design we can pursue the most idealized form and from there compromise so that the project is achievable within the financial, programmatic and technological constraints that the team must work. The team took the view that you should never start with reality; you should always start by identifying the ideal and then compromise as little as necessary.

This idea of hollow columns led the team to discuss secondary purposes that hollow structures serve in biology. These ‘conducting services’, such as the exchange of fluids, gases or sensory information as in the case of nerve cells, led to an idea of constructing the building into the ground beneath to benefit from the steady temperatures that exist a few meters below the surface. Ground burrowing animals like rabbits and foxes use this to regulate the temperature within their burrows. Termites are the accomplished masters of this and can create thermos-regulating structures by using a combination of steady ground temperature and evaporative cooling. For the team, the ideal was to create a network of pipes that could utilize this stable ground temperature to be used as a source of free cooling in summer and free heating in winter.

Developments in 3D printing offer the potential to get even closer to the efficiency seen in biology because there is no cost penalty to complexity in additive forms of manufacturing.

When the team turned to the building’s exterior skin, the design ideal emerged from a careful identification of functional requirements. The main desire was again to optimize the use of daylight – partly for human health, and partly to reduce energy usage. Daylight varies enormously in brightness from zero at night to 20,000 lux on a bright day, but inside, a reasonably steady level is required for working. The team also wanted to minimize heat loss that would otherwise demand an additional source of energy to warm the building during winter months. The ideal identified was a highly insulating and transparent skin with a layer of movable photovoltaic leaves that could allow in exactly the right amount of light, converting all surplus light into usable energy.

The next stages of the project explored the use of complex genetic algorithms to further refine the optimizations between a wide range of criteria. These software tools essentially replicated the process of evolution at greatly accelerated speed, demonstrating the changes which organisms underwent to fit their respective ecological niches over aeons.

Biomimicry offers enormous potential to transform our buildings, products and systems. For every problem that we face – whether it is generating energy, finding clean water, reducing waste or manufacturing benign materials – there are precedents within nature that we can study. All those examples will run on current solar income, and there will be a closed loop in all their use of resources. As with any period of dramatic change, the early adopters of new ideas and new technologies are likely to be those that achieve the greatest success.