Background
In the past few decades, there have been a variety of approaches used to make construction greener and more sustainable. Examples include using solar panels and integrating eco-friendly, biodegradable materials into building design. Biodegradable materials – like organic paints – limit the negative impact on the environment by easily breaking down without releasing contaminants, whereas traditional materials can result in the accumulation of waste products and toxic chemicals.
Why do we need to improve our construction methods?
As an industry, we have a significant impact on the natural environment, economy, and society – from the number of hazardous materials generating pollution to the use of materials that come from increasingly limited resources. Further, as the industry grows, and materials become more limited and thus costly, traditional methods often need to be adapted to keep them fit for purpose. Three critical areas of concern are energy, waste and CO2.
Globally, construction consumes approximately 40% of total worldwide energy production, produces 30-40% of all solid wastes and 35-40% of CO2. By using environmentally conscious building methods like solar technology and increasing our focus on a building’s thermal performance, the industry can incorporate new technologies and make the end design and structure more sustainable.
In the UK, the construction industry is using sustainable construction techniques to help meet their target of reducing CO2 emissions by 50%, with 50% faster delivery and 33% lower costs from initial outlay through the life of a built asset.
Environmentally friendly techniques
One of the main design techniques being adopted throughout the construction industry across the world is green building, which includes vegetation-based roofing. Green roofs are often an aesthetic choice as well as a sustainable one, and the appearance of plants and flowers raises the building’s appeal to investors, workers, residents and visitors. A good example of green vegetation-based roofing is the ACROS Fukuoka Prefectural International Hall where greenery was placed on the slanted side of the building to enhance its beauty. An additional benefit is how the building blends with environmental surroundings while still using as much of the site as possible, thus improving the building’s long-term economic sustainability.
Another environmentally friendly technique being explored involves modular building methods that allow workers to create structures offsite and then transport them to the end location. Offsite construction typically takes less time, and less raw material may be needed to complete a project while still achieving high-quality results. An example of this is Sunderland’s Northern Spire Bridge, where most of the concrete deck components were precast offsite to a high finish. The decision served as a positive step-change to casting the concrete parts in situ, which can result in considerably more noise and mess and require far more workers, thus increasing associated time, costs and materials waste.
Researchers are also looking into how they can adapt current materials to make them more sustainable. Universities often carry out this type of research, with a good example being Cambridge’s exploration of self-healing concrete. Chemical additives are introduced that instil the concrete with reparative properties, which will continue to develop over the material’s lifetime. Findings could result in less maintenance, lower workforce demand, and potentially serve as a new development for a more sustainable and environmentally friendly solution in the long term.
Project lifecycle
When looking at how best to develop and use environmentally conscious techniques, many aspects are reviewed based on whether they will be successful throughout the asset’s full lifecycle. This includes planning, design and construction through to building operation and maintenance and then on to possible refurbishment and, finally, demolition.
When looking at an asset’s operational stage – who will use it and it how – numerous factors can impact a building. For instance, building users produce moisture; therefore, systems must be put into place to ensure efficient moisture removal. The more organic material used in a building the more ventilation is needed, and this can lead to building financing issues. Therefore, a balance must be struck to ensure that guidelines are followed while still using sustainable construction to its full capacity.
What happens after the building has served its purpose also needs to be considered. In the past, this stage of an asset’s lifecycle has often been overlooked, thus creating unanticipated difficulties during demolition. One example of this is a Sheffield city centre project in the early 2000s where several mid-century buildings took a considerable amount of time to demolish. This stemmed, in part, from the original choice of materials and issues like overly complicated reinforcement designs. The result was unforeseen risks and hazards that only became apparent once demolition was being planned.
Future of environmentally conscious building
As the construction industry has become more aware of the vital role it plays in wider society, sustainable approaches to construction have become more widely used and apparent within modern designs. These include walls that self-regulate indoor temperatures and buildings made from living trees such as the Citicape House in London, which incorporates the largest living wall in Europe. In future, environmentally conscious methods such as those mentioned in this article could lead to a new and improved built environment for all. The possibilities are endless and could improve construction efficiency as well as provide economic gains and improvements to physical health.
