Blue Forest’s Senior Designer, Dan Wilson Provides Some Sustainable Building Design Tips.
1. Design the building to limit the users resource consumption (water, heat, power).
This can take many forms, including the use of low consumption technology, such as L.E.D light bulbs and reduced capacity flush toilets, etc. In addition energy saving solutions should be consciously designed into the fabric of the building. The simplest example of this is structural insulation. If a building is well insulated less heat energy is required to keep the internal climate comfortable and subsequently less energy is lost to the outside environment.
Further reductions in heating requirements can be achieved through the use of simple design features like passive solar gain (PSG). PSG is a term used to describe the greenhouse effect created by the interplay between the suns radiation and the windows/glazed areas of the building. Where suitable, buildings should be designed to maximise PSG. A simple way of doing this is to include large windows on the south elevation of the building to naturally absorb more of the suns radiation and subsequently to reduce additional heating requirements. Large areas of mass can be designed into the building to absorb the heat energy (& release it in the winter), clever ventilation and heat transfer systems can be utilized to make the most of the energy and retain it in the building.
As you can imagine, there are a myriad of other design and technological solutions which can reduce the users need for resources. Please contact the Blue Forest team to discuss your requirements.
2. Localise the sourcing of materials.
Localised sourcing is a simple concept, the closer to site that materials are sourced the lower the embodied energy they contain due to the reduced transport requirements. In addition, the use of local materials supports the local economy.
3. Reduce wastage by basing the dimensions of your design around the dimensions of standard building materials.
As with many of the best sustainable design concepts this is simple common sense. If you design your building around multiples of standard material dimensions then there will be less cutting and so less material, energy and time wasted.
A simple example is Ben Law’s famous woodland house. This is a round-wood timberframe structure (using wood harvested from site). The walls are insulated with straw bales and finished on the inside with lime plaster and wood cladding on the exterior. Ben based the dimensions of his design on the size of a standard straw bale. For example, the footprint of the building is 18 bales by 12 bales. By doing this there was no need to cut any of the bales so wastage and build time were reduced.
4. Create a building utilizing high quality materials. A design which is strongly desirable to inhabit will ensure the longest lifespan possible.
It makes sense to create a building which lasts for a long time. This is obviously far more sustainable than creating a building which has to be replaced every generation. Unfortunately, a structure that is built to last will cost more initially and this is not popular in today’s world where short term profits are king. The old mantra “buy well, buy once” springs to mind.
In today’s world many products are built to fail and to be replaced as trends change. If a building is thoughtfully and well designed it will be a delight to inhabit. The user will develop a strong sense of ownership and affection for the structure which encouragers them to take better care of the building and maintain it to a higher standard, resulting in an extended lifespan.
5. Seek design inspiration in the vernacular in the hope of creating a building which is appropriate to and in tune with it’s environment.
Vernacular architecture has evolved over many years to suit the local climate and environment and to make the most of the immediately available local materials.
Many useful design features can be learned by studying vernacular architecture. For example, in some regions of Scandinavia, where there are strong prevailing winds, the lowest elevation of the building is orientated to face the wind and trees are traditionally planted at the rear of the house. When grown the trees improve the aerodynamics of the building. If you built a large modern home in the same area with the largest elevation facing the wind and with a an open garden it would not be as pleasant to inhabit.
6. Minimize the buildings impact upon the site (e.g. low-impact foundations, minimal site clearance, etc)
One should always aim to minimise the buildings impact on the surrounding environment. A simple example of how this can be achieved can be seen in the foundation requirements of two different types of buildings. We will compare a timber framed house to a traditional English bricks built house.
The brick house has large subterranean foundations, built using a lot of concrete. This design requires a high amount of energy to excavate the foundations and level the site. It also requires lots of concrete (high in embodied energy) to construct the foundations.
The timber framed building can be raised upon a number of posts, supported with the use of smaller pile foundations. Less work is required to level the site as the height of the posts can be adjusted to ensure the buildings sub-frame is level. Because of this, the development will use less concrete, require less landscaping and therefore use less energy.