28 July 2020

Wood health

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Three years ago, TRADA’s Timber 2017 Industry Yearbook featured an article titled ‘Is wood good for your health?’, which considered how the choice of materials we surround ourselves with could affect our well-being. It was an exciting time as building occupant well-being was rising up the agenda and the first building in Europe to achieve WELL Gold Certification through the WELL Building Standard™ was the Cundall office at One Carter Lane, London, in November 2016.


At the time, the logic for using wood as a construction material was simple and built upon the increasingly recognised health and well-being benefits of the forest resource as an asset. It considered that through ‘biophilia’ – our connection to nature – we respond, heal, learn and relax better in environments that mimic nature. Wood as a natural material is a strong proxy for nature, bringing us warmth, diversity of pattern, thermal comfort, and acoustic and aesthetic qualities.


This article discusses what has happened since then and glances to the future, focusing on three topics:

  • the evidence for health qualities of wood
  • building momentum
  • the opportunity for increasing specification of wood using health qualities.


Evidence for health qualities of wood

It is incredible to think that a material as ancient and widely used in our built environment as wood could have qualities that we are only just beginning to quantify. At last year’s TTJ Wood and Wellness conference in London, TRADA’s briefing document ‘The role of wood in healthy buildings’ was launched, documenting the scientific evidence for the positive impacts of wood on people in buildings.


Empirical scientific evidence is key to our understanding, but we also have to judge that evidence: it is not all the same and often cannot be directly compared. For example, we have to consider the experimental set up, the inherent bias, the data sample size, the demographic of the people participating in the study, culture preferences etc. Scientific evidence is key, but we must also value the distillation of years of anecdotal evidence and instinct. This shapes designers, craftsmen and others drawn to work with wood, creating a deep experiential quality to their buildings, products and interiors.


The global evidence suggests that, from studies of the perceptions of wooden surfaces compared with other materials, a ‘wood preference’ exists. People who are asked to compare materials by looking, touching and smelling material samples prefer wood to steel, plastic, metal, stone, ceramic, brick and aluminium. This is connected to the naturalness of the wood material and extends further as solid wood is preferred to wood-based materials and, perhaps no surprise, that real wood is preferred to false wood. When asked about rooms with different amounts of wood present, mock-ups or visualisations of wood present in a room (from no wood to everything wood) there seems to be a limit, with some wood present (for example the floor and furniture) being consistently the preferred option.


People have positive attitudes towards wood in interiors. Wood is commonly perceived as natural, warm and healthy, and is often preferred over other materials.


Healthcare and education

The global evidence of the physiological and psychological benefits of wood is somewhat sparser, but some encouraging work published in Canada by Augustin and Fell found that, in healthcare environments, natural materials and views are associated with better patient outcomes with respect to recovery times, lower pain perception and positive dispositions. For education, Kelz et al studied the use of wood in Austrian classrooms and found that, over the course of a school year, pupils’ heart rates significantly decreased in a solid wood classroom but increased in the control non-wood classroom.


There is good evidence that wood has a positive impact on human psychology and physiology. There are only relatively few studies, but they are long term, thorough and create a movement towards using wood for health benefits. These promising results should be replicated in the UK and/or Europe, with more subjects and different age groups to build upon these exciting findings. This would be hugely beneficial in accelerating uptake of specifying wood for health.


Building interiors are experiential – instinct and first experiences are important. Is wood being specified for health and wellness qualities now? Globally there are some examples of wood specified for its health and well-being qualities. It is repeatedly specified as a versatile, natural, low-carbon, beautiful material, but health and well-being is a quality specifically embedded in some projects in Australia (Wood Housing Health, Humanity), Canada (Wood in Healthcare) and the US (Thinkwood case studies). In many cases the function of the building – mental health centre, children’s hospital, care and assisted living complex, healthcare centre – might have been driving its consideration.


Many people prefer wood as a material and there is increasing confidence that the positive impacts wood can have on occupants of buildings can be measured, but these health benefits are not currently specified.


Building momentum

We must continue to build this momentum, expand and share experiences and new studies. TRADA’s Case Studies showcase fantastic buildings celebrating the diversity of wood and its ability to deliver and be part of our built environment. It would be valuable to revisit and extend this building evaluation to the health and well-being of the building occupants, and understanding and then communicating those tangible benefits to a wider audience.


The opportunity for increasing specification of wood using health qualities

Certification schemes for whole buildings are a good route to examine, although even with health-dedicated schemes reference to wood will not be directly found in many places. We have seen that a core tenet of biophilic design is contact with nature and analogues for nature – natural things. Wood is a proxy for nature, each element being unique and natural. TRADA’s Wood Information Sheet Specifying timber for healthy buildings reviews, in Tables 6 and 7, how the qualities of wood impact within certification schemes, such as indoor air quality, visual comfort, biophilia, thermal comfort, acoustic comfort etc. We are now considering the next step to map the credits available to wood in certification and assessment schemes, in place of an alternative material, for specific applications such as flooring, furniture, doors and interior cladding panels.


Specifying timber for healthy buildings explores the possibilities for the specification of wood for healthy buildings, to encourage delivery of interiors that positively impact on our well-being. It recognises the importance of the type of project, with particular opportunity around refurbishment and fit-out (RFO) projects. This is vital as much of our existing building stock will remain with us for many decades and be refurbished and repurposed. It is second nature now for us to minimise emissions in the selection process for preservatives, fire retardants and glues in products, but we also need to push this to operational issues such as the aftercare and cleaning products that we recommend.


Making a compelling case

To further enable specifying timber for healthy buildings it is essential to understand more about the qualities that wood delivers, gather more evidence as case studies and have a consistent compelling case for us to communicate. We need some or all of the following to accelerate this uptake:

  • a collaborative sector-backed research strategy to articulate and ‘attach’ wellness qualities to wood products
  • occupant monitoring of wood-rich and control buildings providing a catalogue of UK exemplar wood-rich buildings with health and wellness credentials
  • communication of our findings as evidence turned into targeted guidance to enable specification of wood for its wellness qualities.


Wood products have an exciting role to play in contributing to positive indoor environments where the benefits to our health and well-being manifest as improved experiential qualities and building outcomes. These outcomes include:

  • recovery rates in hospitals
  • education success in school
  • comfort in our homes
  • better business outcomes in our offices.


The health qualities in future will be more readily articulated so that wood solutions can be proposed by designers to meet clients’ needs such as low carbon, strength, durability but also the significant values of health and well-being.


About the author

Ed Suttie, Research Director, BRE


This is an extract from the Timber 2020 Industry Yearbook. Download the full article, including supporting images, references and further reading, here


For more information about healthy buildings, visit our dedicated area