Background
This report responds to a call for proposal to recommend an engineering solution to a specific problem in the built environment sector.
Cement is inarguably the most used and crucial construction resource since civilizations came into existence and more buildings that are bigger and taller will inevitably be constructed in the future. Rodger (2018) states that most of our concrete in the world is being used to construct buildings and that the main ingredient of concrete is cement, whose production contributes to 8% of the world’s carbon emissions, which is equivalent to 2.2 billion tons of carbon dioxide per year.
According to Climate & Clean Air Coalition (CCAC), the process of producing bricks in kilns releases large amounts of pollutants such as sulphur dioxide and black carbon into the atmosphere. These effects are not easily reversed and will accumulate in the earth’s atmosphere much to the suffering of future generations.
The Intergovernmental Panel on Climate Change (IPCC) mentioned in their special report that it is essential to maintain global temperature within 1.5 degree celsius . A one-degree increment of global temperature can result in a drastic increase of the atmospheric temperature.
Based on National Oceanic and Atmospheric Administration (NOAA), the global temperature in September 2009 was 0.62 degree celsius. Currently, the global temperature is at 0.95 degree celsius. Despite it being under 1.5 degrees, there was a 0.32 degree increase of global temperature within a decade.
Dr Koh Poh Koon, Senior Minister of State for Trade and Industry, mentioned that Singapore generated 52.5 million tonnes of greenhouse gases in 2017 which contributed 0.11% of global emissions, that equates to 8,000 tonnes of CO2 per capita in that year (Tan, 2019). According to Dr Muhammad Eeqmal Hassim, senior research scientist with the MSS Centre for Climate Research Singapore (as cited from Channel News Asia), with the rise of carbon emission, it will lead to an increase of Singapore’s daily temperature from 35 to 37 degrees celsius (Hassim, 2019).
The most direct way Bricknology can contribute to the reduction of climate change is through convincing BCA to adopt the idea of using mycelium bricks in Yio Chu Kang private housing estate as a pilot programme. By implementing the use of mycelium bricks as a pilot programme in Yio Chu Kang private housing estate, the team hopes that Singapore could set an example to the world that mycelium bricks can help in reducing the overall global greenhouse gas emissions problem.
1.1 Current practices for Yio Chu Kang private housing
The team had observed that the bricks used to build the internal structure of the house in Yio Chu Kang private housing were made up of clay and concrete.
Clay bricks
1.2 Problem Statement
Building Construction Authority (BCA) to authorized the use of mycelium brick for all future construction. However, BCA is not implementing the use of mycelium bricks despite its potential.
1.3 Purpose Statement
The purpose of this report is to convince Building & Construction Authority to adopt the idea of using mycelium bricks and initiate a pilot project in Yio Chu Kang private housing estate.
2. Proposed Solution
The team has referenced online research done for sustainable bricks and have decided to propose a solution for BCA to consider:
2.1 Use mycelium bricks in place of conventional bricks
The team conducted interviews with the construction supervisors and workers in Yio Chu Kang private housing during a site visit. The team was told and observed that bricks used in Yio Chu Kang private estate houses to build internal walls were mainly by concrete and clay bricks.
The production of making these bricks involve heating the bricks to high temperatures which produces a high amount of CO2 as a by-product. It is also noteworthy that the production of concrete and clay bricks produces a ratio of 1 tonne of bricks to about 250kg of CO2 (Rathi, 2017).
Mycelium is an organ belonging to fungi that plays the role of digesting and absorbing nutrients for the fungi. The current technique for growing mycelium bricks incorporates a process of decomposition and drying.
Mycelium bricks reduces the carbon emission of producing the same number of concrete or clay bricks by a large margin.
3. Advantages of mycelium bricks
3.1 Good physical capabilities
Mycelium bricks is fifty six times per cubic meter lighter than your typical conventional bricks. It is capable to withstand a high amount of compression force. Mycelium bricks can be grown in a controlled environment where the mycelium is grown in such a way so as to produce desired physical capabilities. In one such experiment, the results are a mycelium brick that is 200,000 times more ductile than steel, 10,000 more rigid than brick while still able to support the weight of 50 cars (Abrams, ???). As proven from architectural structures, it is able to withstand external factors such as wind and rain.
3.2 Fire resistance
Although mycelium does take a shorter time to ignite in comparison with clay and concrete, the beauty about mycelium bricks is that the moment the outer layer is burnt, a layer of char forms on the surface of the mycelium which actually increases the flame resistance of the entire brick itself. This results in the bricks actually being able to last longer in prolonged fires, maintaining its structural integrity long enough so that the building does not collapse under its own weight., leaving room for people to escape.
3.3 Good thermal insulation
Mycelium insulation has way better R-value and EPS R- value as compared to conventional insulation boards.It does not absorb heat as fast as the conventional boards. It is also thinner and lighter which makes it easier for construction process.
3.4 Environmental effects
Mycelium are 100% biodegradable and they can be found in abundance on the planet. It does not release any volatile organic compounds. As it is made up of fungi, people will get the misconception that overtime it will turn rotten and start releasing foul smell and release harmful gases. Thus it will not release any external harmful effects.
3.5 Resources and production
The production of mycelium does not cost much as it uses bio-based materials and is biologically grown. Even pieces of agricultural waste materials and natural bio materials can be used to make mycelium bricks. It does not rely on factories for producing mycelium bricks unlike conventional bricks. Thus hugely reducing the use of artificial energy and the amount of CO2s to produce mycelium.
3.6 Social benefits
4. Disadvantages of mycelium bricks
4.1 Weak compressive strength
Mycelium bricks can only withstand 30 psi whereas a concrete block can withstand 4000 psi to 10,000 psi. Mycelium bricks can not support as much weight as compared to a normal concrete block.
4.2 Production
As mycelium takes time to grow, it might take a few days to weeks to be able to use it as a component to make the bricks. External factors such as temperature and moisture might delay the growth of the mycelium.
4.3 Long term
Mycelium bricks are still in the early stages in their line of production. As a result, the full capabilities of these bricks have yet to be known. Much of its credibility is theoretical as to how long it is able to last in residential and non residential buildings. It might be the solution to replacing all conventional bricks but because mycelium bricks have only been around for about 5 years, no concrete research is available for these bricks in a 50 year lifespan. No matter how much research and claims from experts that says it will last, it will only remain as projections. The only thing we are able to fully trust is to wait until it reaches its maximum brick lifespan.
