What Are Green Buildings?

A sustainable building in Malaysia (Wikimedia)

Some time ago, during my normal musing, a thought came to my mind. It was about the colour GREEN. It was in the form of the rhetorical question: Why did God choose GREEN as the colour for vegetation? Didn't he see blue or red or even pink? Why must it be GREEN? 

After pondering for a while, I gave up the thought as I couldn't get the answer. I assumed the colour GREEN is as important to God our creator as it is significant to us human beings. I mean, If it were not so, why would God choose green out of a range of other colours? But that's by the way. 

Green is one of the many colours in the colour spectrum. In colour chemistry, green is a secondary colour that can be gotten from a mixture of yellow and blue pigment. I learnt that during my industrial training at a paint company at Uyo.

GREEN is a cool and stable colour that symbolises a new beginning, vegetation, environment or better put, nature.

What is a Green Building?

I asked a young adult the other day if he knew what a green building was, and he naively responded this way; “a green building is any house that's painted with green colour”. I couldn't help laughing. His response reminded me of the funny definitions we would often use for greenhouse gas back then in junior secondary until a senior student, who was conversant with the subject, corrected us one day.

Of course, the guy was right, literally correct, only that he didn't know the term had a technical definition beneath it. There are many people around who don't quite know what the term means; perhaps, they would've responded the same way too.

Green Building refers to both the physical structure as well as the practice of building such structures that are environmentally responsible and contribute towards reducing carbon footprint.

Green Buildings are those buildings that generate as much energy as they consume; resulting in a net-zero energy footprint. They are simply energy-efficient buildings.

ICMA (International City/County Management Association) defines green buildings as an integrated approach to designing and building cost-effective, energy-efficient, healthy, and eco-friendly living and working environments.

The choice of materials has a significant role in designing green buildings. During construction, materials that are recycled, reusable, non-toxic (plant materials like bamboo and straw), and renewable are primarily preferred over other materials. Furthermore, green buildings need structural and design innovations to achieve the goals of sustainability.

In a broader sense, green building is not limited to only designing a building. The entire life cycle of a building (design, construction, operation, maintenance, demolition, and renovation) comes under the green building concept.

A striking feature of green buildings is the use of building materials that can add energy efficiency and resource responsiveness to the nely built environment.

HISTORY OF Green Buildings

Architecture has evolved exponentially in the course of our human history or civilization. Many forms of home designs have emerged like bungalows, flats or apartments, terraces, semi-detached, detached, duplexes, penthouse or maisonettes, etc. But the basic idea of home stays the same: it’s a safe place to stay. 

The green building initiative can be traced back to the 1960s when American architect Paul Soleri proposed the concept of ecological architecture. Soon after, another American architect Ian McHarg published a book titled “Design Integrates Nature” in 1969. Several experts loosely agree on the fact that this book paved the way for the official birth of green ecological architecture. 

Green Architecture

In the subsequent years in the 1970s, the global energy crises compelled further advancement in this trend as designers focused more on energy-efficient buildings with provisions to reduce energy consumption and use alternative renewable energy sources. There is a direct relationship between the increase in human population, growth in building construction and energy consumption. 

Scope of green building

A green building is sometimes called a sustainable building, as sustainability is one of the main objectives of the green building concept. Also, a Green Building is not necessarily the same as a Smart building, but a smart building can help achieve a green building since they're often eco-friendly. Almost all multi-story green buildings are designed to accommodate a robust and centralized building automation system (BAS) for the energy, air and water conservation characteristics.

A building can be green if it fits certain criteria, listed as follows;

• The materials and resources used are non-toxic and sustainable.

• The design integrates energy efficiency and water efficiency features.

• Energy sources used in the building should be renewable energy.

• Water conservation should be included as part of the sustainable design.

• Zero pollution and minimal waste generation measures are adopted.

• Indoor air quality is good and natural.

• The design, construction, and operation phases have no negative environmental impact.

• Occupants enjoy a superior quality of life.

Homes, offices, schools, hospitals, community centres, commercial buildings, and other existing buildings can be green buildings, provided they adopt green building practices and fulfill other green building requirements mentioned in the list above.

WHY DO WE NEED GREEN BUILDINGS?

The short answer is that we need green buildings because they are simply sustainable. But there is a need to expatiate further into its import and purport.

The exponential population growth in the past few decades has led to the relentless growth of modern cities and incessant new construction. This has contributed to catastrophic environmental degradation. Adding to that, the need for buildings and habitats is only going to increase in the future.

Studies have shown that the energy consumption of buildings surpasses other sectors in different regions of the world. The negative impact of energy consumption on buildings has a significant effect on the environment and people's well-being. The increase in energy demand for buildings leads to the need for the deliberate adoption of smart strategies towards mitigating the effect of climate change and high-energy consumption in the context of the building sector.

Energy-efficient appliances and sustainable urban and building design have been suggested as measures to reduce energy demand and consumption. There is an urgent need to adopt these measures in Nigeria, especially in the design of buildings to reduce high-energy demand and consumption.

 A significant aspect of the call for sustainable buildings is a call on building designers to devise ways of designing buildings that have little or no adverse effect on the natural environment and people's well-being. It has been largely argued that optimisation of building design is key to achieving the commitment to lowering GHG emissions to a significant amount by 2050. 

Excellent building design can leverage the benefits of natural systems towards a significant decrease in the energy consumption of buildings. Prudent building design using appropriate passive and active technologies can greatly reduce energy demand, consumption and the contribution of greenhouse gas (GHG) emissions by the building sector. Correct design of the building envelope can considerably improve energy efficiency and help to realize heating and cooling targets. A study by Al-Tamini showed that the extent to which non-renewable energy resources are required for building services is determined by building design. 

Okba also argued that proper design of the building envelope could lower the total cooling load on buildings thereby reducing overdependence on air conditioning, corroborating this view. Other studies have shown that careful design of the building facades can decrease the energy demand of buildings. In line with this argument is the opinion of Latha et al that proper building design using the building envelope is key to reducing the heating and cooling load in buildings.

The design of buildings can have both positive and negative impacts. Poor building design can contribute greatly to the increase in the building’s energy consumption. Many buildings found across Nigeria are thermally uncomfortable to stay inside without the use of cooling systems.

Sustainable architecture presents suitable design solutions to reduce the negative impacts of buildings on the environment without compromising building users’ comfort. Many residential buildings in different climatic regions around the world have been found unsuitable for users due to poor design, which does not consider the local climate.

Green Building Innovation

Therefore, green building innovation provides a sustainable solution to deal with the global environmental problem and is vital to avert the undesirable consequences of global warming and harsh climate conditions. Green building is a potential solution to curtail the negative impacts on the natural environment.

The green building initiative is definitely a step in the right direction. Global cooperative practices such as the enforcement of the international green construction code are necessary at the moment to undo the worrying climate action.

Green construction materials sourced directly from natural resources should also be included in the national green building standard framework.

THE SITUATION IN NIGERIA

In Nigeria for instance, some buildings are indiscriminately set up without consideration to the local climate. For example, proper ventilation through external shading has been identified as an important means of enhancing building energy efficiency in hot-humid climates. Hence, there is an urgent need to encourage and advocate green building designs that are responsive to the local microclimate.

In the Nigerian building sector, there's a need to achieve energy efficiency by decreasing the energy demands of buildings. One of the key strategies being adopted for the substantial reduction of energy demand in the Building Energy Efficiency Guide for Nigeria is the bioclimatic architectural design approach. Hence, intelligent design of buildings, especially the building envelope, can considerably improve energy efficiency and help to realize heating and cooling targets.

ADVANTAGES OF GREEN BUILDINGS

#1. Improved quality of life

It's no secret that our surroundings significantly impact our health. Green architecture focuses on sustainable interior design elements, including ergonomic design features, improved lighting sources, optimum thermal conditions, and better air quality. Due to these features, occupants living or working in green buildings experience improved health, lower stress levels, and a better quality of life altogether.

#2. Low water wastage

The green building concept puts great importance on water efficiency. A water-efficient plumbing system is incorporated to improve water conservation and lower water wastage. Moreover, a specially-engineered water purifier and storage system enables water recycling. This is an important step towards saving vital natural resources.

#3. Increased efficiency through shared resources

Local shared resources are becoming scarce, especially in overcrowded cities and urban settlements. Green building practices consider sharing vital resources like water and energy and saving them from overexploitation. The sharing of resources also helps in close-knit community development.

#4. Achieving energy efficiency through renewable energy resources

Energy efficiency is a primary goal of any green building design. This includes the energy required during the construction as well as the operational lifetime of the building. Innovating the building design to accommodate better natural ventilation and light can reduce dependency on external energy sources for heat and light. 

Several other structural and technological innovations to enhance energy efficiency in a building have been discussed in the later section of the article.

#5. Minimal carbon footprint

As per the Environmental Protection Agency (EPA) findings, buildings alone account for about one-third of all greenhouse gas emissions in the USA. Therefore, large corporations, public sector enterprises, and even people in large are enthusiastically making efforts to achieve carbon-neutrality goals through green initiatives. Using low-carbon or zero-carbon building materials in green buildings helps achieve these decarbonization goals.

#6. Green buildings are more highly-priced than conventional ones.

Green buildings witnessed a 10% or greater increase in asset value in the United States. Client demands and healthier buildings are two primary reasons for the increase in green technology construction across the country.  

#7. It boosts the environmental credibility of a business.

For a business, occupying a green and eco-friendly building can help it earn some credibility. Constructing LEED-certified buildings highlights your business’s passion and commitment to sustainability. It can improve your brand’s positioning and help you attract more eco-friendly investors and clients.

#8. Green buildings enhance the public of their builders and executors.

Adopting green building practices and technology as a builder can also help improve your construction business image and enhance the existing construction business ecosystem in Nigeria. Going green can be a differentiator for your construction company. More clients and owners will care about the green construction initiatives you bring to the table.

DISADVANTAGE OF GREEN BUILDINGS

To the best of my knowledge, the only disadvantage of Green buildings is that they are expensive to construct, design, and maintain. It is relatively more costly to put up than traditional buildings. This is so because most green technology used in green buildings are highly-priced. Of course,  environmental construction methods have a higher cost. 

As a builder, before you use green technology construction, you should understand the green building construction cost.

From the front-end engineering design (FEED to Procurement and Construction), net-zero-energy buildings can be created using complex and intricate designs made available by 3D concrete printing technology. In other words, green buildings are more difficult to achieve than traditional methods.

HOW TO MAKE BUILDING GREEN

Selection of sustainable materials. As I mentioned earlier, this is very key.

- Sustainable Room Design

Green buildings are built from sustainable building materials that are renewable, recyclable, and reusable. Non-toxic plant-based materials (like bamboo and straw) have little or no negative impact on the environment and are thus, preferred over other building materials.

- Structural innovation

Architecture and designers around the globe are finding new ways to accommodate better sustainability in terms of energy, water, and light. Innovative designs include large windows and open spaces for better ventilation and natural lighting. Integrating provisions for rainwater harvesting is another innovative feature to enhance water conservation in residential and commercial buildings.

- Green Building Structural Innovation

For instance, BiPV (Building-integrated Photovoltaics) is a game changer for meeting sustainable goals. Integrating Photovoltaics or PV panels onto the basic structure during the construction phase of a building can make the building self-sustainable for electricity needs. This can reduce the dependency on the main electric grid, thereby curtailing the electricity network expansion, which is one of the major contributors to CO­₂ and greenhouse gasses.

- State-of-the-art technology integration

Integrating ArchiTect(Architecture + Technology) can substantially contribute to mitigating the challenges of the wide-scale adoption of green construction. Innovative technological solutions like BIM (Building Information Modelling), BMS (Building Management System), or IBMS (Integrated Building Management System) are already changing the face of the construction industry. 

These technologies help to achieve better decarbonization, improved eco-friendliness, and higher energy efficiency.

- Towards a greener planet through collective responsibility

The responsibility to achieve carbon neutrality and reverse the negative environmental impact lies on everyone’s shoulders. The public-private partnership is necessary to deal with the challenge of finding a sustainable design and building solutins without negatively impacting the environment.

Federal & local governments, including the city council, can incorporate green building principles on the administrative level. They are also responsible for establishing a green building standard framework to achieve sustainable development goals.

On the other hand, people are largely responsible for adopting eco-friendly practices. The real change will be visible when people, in general, will push for implementing green building concepts in their homes.

The World Green Building Council, a United Nations Global Compact member, is an action network comprising more than 70 national-level Green Building Councils. The organization acts as a global supervisor to enforce the green building standards code and international green construction code throughout the world.

Moreover, the organization is on a mission to transform the strategic building and construction sectors by optimizing existing practices with sustainable construction practices. It aims to achieve better climate action, health, quality of life, and resource distribution through collaborative research and actions by the various stakeholders in the construction sector.

Currently, the council has associated itself with the World Bank to promote the Green Building concept in developing countries and emerging markets through the Excellence in Design for Greater Efficiencies (EDGE ) Market Transformation Program and certification.

Any physical structure can be flagged as a green building if it fits into the criteria of using recyclable and renewable materials for its construction and is optimized for high energy and water efficiency. As the construction sector is one of the latest contributors to greenhouse gas emissions, the green building concept can be a potential solution to reduce carbon emissions. However, it needs strategic public-private cooperation and investment apart from policy reformation.

Energy efficiency in buildings is a new concept in Nigeria and little or no efforts have been put in place to make the design of buildings energy-efficient in the Nigerian building sector. Key institutional frameworks have been established no doubt. 

The first Building Energy Efficiency Guide (BEEG) for Nigeria was released in 2016, while the Nigerian Building Energy Efficiency Code (BEEC) was launched in August 2017. This framework will help the design of energy-efficient residential buildings in Nigeria and is expected to significantly reduce the challenges associated with climate and control the energy consumption of buildings in Nigeria.

However, to achieve energy efficiency in buildings, there is a need to identify specific design and construction variables that will aid comfort and decrease buildings' energy consumption. These variables should be well appropriated and emphasized under building form, building orientation, floors, walls, fenestration (openings like doors and windows) and roofs.

The incorporation of these energy-efficient measures into subsequent housing intervention will no doubt improve people's well-being and the human environment.

This is excerpted from a lecture I gave at the 2023 AGM of the National Association Of Building Students (NAOBS) of Nigeria.