- Use energy, water and other resources efficiently
- Reduce waste, pollution and other negative impacts on environment
- Maximize occupant health and productivity
- Decrease life cycle costs
- the design of our homes plays an essential role in the quality of our lives, comfort level and health;
- the design of our schools has a lifelong impact on our children who study in them, in terms of influencing students’ attention and health;
- the design of our workplaces influences employee productivity and health and the business success of our companies;
- the design of our hospitals has an impact on patients’ recovery period and overheads in healthcare institutions;
- the design of our cities and communities strongly defines their economic and social dynamics.
Green building is perhaps best understood as a convergence of two movements: (1) an architectural movement emphasizing environment conscious, integrated, efficient and innovative design, and (2) an environmental movement arising from the principles of sustainable development.
In that context, GREEN BUILDING:
- represents an intelligent approach to energy
Green building encourages setting energy goals and target from the start of the project, taking advantages of building site and climate attributes to reduce heating, cooling and lighting loads, integrating landscape design for shading and windbreaks, facilitating the use of public transport, incorporating renewable energy where possible, etc.
- protects our water resources
Green building tries to reduce water use and protect its quality, by using water efficient fittings and fixtures. Other technologies such as rain water harvesting, recycling and reuse of grey water, etc. are also being used.
- reduces waste and pollution
Waste minimization requires careful planning throughout the design, build and occupancy phases. Green building minimizes negative impacts on the environment by “Reduce, Reuse and Recycle” strategies. For example, by reducing impervious area, we reduce stormwater runoff and reduce surface temperature. Reusing previously developed sites or existing structures is one of the best ways to limit the negative impacts of development. And certainly, there are a myriad of opportunities for recycled materials use in site development.
- promotes health and well-being of all building users
Green building emphasizes on providing adequate supply of fresh air throughout the building premises, which is achieved by good ventilation which maintains high indoor air quality, and avoidance of materials and chemicals that can cause emissions of harmful gases.
It encourages extensive use of natural light to illuminate rooms and makes sure that their occupants have a nice view of the surrounding environment, which not only provides the building users with great amount of comfort and a possibility to enjoy the surroundings, but also reduces the need for artificial room lighting.
It is a design that “appeals to both eyes and ears”. In fact, when it comes to schools, health care institutions, private homes and workplaces, acoustics and sound insulation play an important role in providing an ambiance that is good for concentration, recovery as well as for enjoying work and spending time in one’s own home.
By providing a pleasant indoor temperature, it contributes to the creation of a good atmosphere and a pleasant microclimate in rooms where people spend most of their time. Humidity control and air movement control are all important for keeping thermal comfort, but also the biggest consumers of energy. Green building encourages the use of passive cooling through proper use of shading and natural ventilation, or simple but effective equipment such as ceiling fans.
- keeps our landscape green
Particular attention is paid to site selection, preservation of existing vegetation or the addition of vegetated area during green building design. Vegetation can reduce heating and cooling needs, clean the air and reduce heat island effects, among other benefits.
- connects us
As early as at the design stage of a building, thought is given to shortening the distance between people’s homes and workplaces or other social locations, which results in a reduced environmental impact of personal vehicles as well as of road and rail traffic in general. Green building encourages the use of environmentally friendly means of transport, such as bicycles and other green transport modes.
- Looks at the costs of a building over its entire lifecycle
Green building considers costs over the entire life of the building, whereas conventional building is often focused on initial design and construction costs.
GREEN BUILDING CERTIFICATION
GREEN BUILDING CERTIFICATION SYSTEMS
Green Building Certification Systems (such as LOTUS, LEED, Green Mark, etc.) are necessary to evaluate if a building is a green building or not.
A Green Building Certification System is a framework for:
- Integrating sustainable (“green”) measures to the design, construction and operations of buildings
- Setting benchmarks and targets for sustainable measures being pursued
- Verifying how sustainable a building is
Various green building certification systems have been developed worldwide.
In 1990, the first version of BREEAM was launched in the UK.
In 1998, the first version of LEED was launched in the US.
In 2002, the Green Building Council of Australia introduced Green Star rating system.
In 2005, the Building and Construction Authority (BCA) of Singapore introduced Green Mark rating system.
In 2010, Vietnam Green Building Council (VGBC) introduced LOTUS, the first green building rating system that considered Vietnam’s building regulations, climate conditions and construction pratices.
In the last three decades there has been a significant evolution in the way rating systems assess the building sector. In the early 1990s the assessment methodologies were developed with the main focus in design stage, where the actual construction was paid less attention. At the start of the 21st century, the trend has gone in reverse, where most rating systems attached much more significance to the actual construction and less focus in merely building design. At the same time, since 2006 a new trend in green building rating has emerged, where the main focus is now on the form of sustainable performance. This recent trend has greatly expanded the scope and implications of green building. As the attention continues to shift to the construction and operational stages, the green rating systems will evolve accordingly and may have a powerful effect on the future configuration of the building sector.
UNDERSTAND YOUR MOTIVES
Knowing your reason for pursuing green certification for your building sets the tone for the rest of your project. Common motives include:
- Reducing operations and maintenance costs
- Keeping building occupants healthy
- Protecting the environment
- Differentiation from market competition
- Corporate mandate
CHOOSE A CERTIFICATION PROGRAM THAT SUITS YOUR NEEDS
Generally, you’d choose a program that serves your motives while considering the complexity, costs and benefits of certification. Take a look the criteria in each certification program, then assess what you already have or can easily achieve and how far you can go within your budget.
Two commonly used green building certification programs in Vietnam are LEED (developed by US Green Building Council) and LOTUS (developed by Vietnam Green Building Council). There are notable differences in costs of certification, baselines and complexity between the systems.
COSTS OF GREEN BUILDING
Higher first costs are often quoted as the foremost reason by investors who choose not to build green. In the early days of LEED, uncertainty regarding the system’s requirements coupled with inexperience resulted in substantial cost premiums for LEED-certified buildings, as high as 15-25% above conventional construction costs in some cases. Not surprisingly, the added cost of green construction meant many project teams stuck to conventional practice.
Today, as the green building industry has matured, sustainable building products and technologies are readily available and more affordable. Several studies have documented that the “green premium” is much less than initially feared.
What are the cost implications?
Many studies indicated that construction costs (hard costs) of green certified projects are well within the range of non-green projects. However, there still some cost items that are indeed directly related to green certification. These costs are mostly soft costs. These costs include:
- Registration and assessment fees
- Cost of documentation time and effort
- Cost of extra research and design
- Cost of commissioning and modeling for compliance
- Additional construction activities for compliance
1. The fees
The most direct cost is also the smallest: the fees you pay to the assessment organization (VGBC for LOTUS, GBCI for LEED) to register and then to certify your project. For a new construction, these fees are roughly $0.3/m2 for LOTUS and $0.6/m2 for LEED, depending on the size of the project.
2. Cost of Documentation time and effort
Either for LEED or LOTUS, someone has to compile and submit the documentation and generally manage the compliance process. This cost could be for an outside consultant hired just for that task, someone on the staff of the design firm, the contractor, or the owner. It could be tough for someone doing it for the first time, but much easier for someone who has done it and has an effective tracking system.
It helps if the team is experienced and each person doesn’t need too much coaching to provide her pieces of the documentation. It also depends how many credits you’re going after, and, to some extent, which ones. It may take a few hundred hours (around 200 hours) to pull everything together for a big complicated project; simple and small projects should take less time and effort.
3. Cost of extra research and design
To realize any high-performing building the team must develop a range of scenarios, run simulations to determine how they will perform and prepare cost estimates to price them out. They also must investigate alternative products and materials and explore the feasibility of new technologies. All these steps take time and effort – how much depends a lot on how experienced the team is and how aggressive the performance goals are for the project.
4. The cost of commissioning and modeling for compliance
Commissioning may seem like a big investment, but it’s cheap compared to the cost of call-backs, fixes, and inefficiencies that are likely if you don’t do it. For this reason, many large owners, require commissioning for all their projects, so for them it is not an extra green cost (they’d do it anyway). Commissioning costs may start at $10,000 and go up for more complex projects.
Energy modeling is different. While energy modeling should be used to inform the design process for every building, they are most useful during early design phases. The models that are required for LEED or LOTUS documentation, on the other hand, are an added step, done late in the design process and often with different parameters. They may start at $5,000 for smaller or less complex projects and goes up for more complex ones.
For small projects pursuing LOTUS, it is possible to earn energy points using the prescriptive path without doing such a model.
5. Costs of construction
If the design team is experienced and the goals aren’t too aggressive (Certified or Silver, for example), there may be no overall added cost because most cost increases can be offset with savings somewhere else. (For example, a smaller HVAC system resulting from a more efficient envelope).
If a project only aims for a minimum green goal (for example, LOTUS Certified), there are many low-cost green measures that can reasonably be incorporated in most situations, such as:
- An improved building envelope with lower WWR, using concrete block (with proper installation and good quality brick) and some shading mechanism;
- LED lighting
- Efficient HVAC equipment (refer QCVN 09:2017)
- Efficient water fixtures
- Non-baked material for interior partition
- Low-VOC paints
The above six measures can already help projects go a long way towards minimum level of LOTUS Certification. From here, projects can targets a wider variety of sustainable measures for higher green goals, depending on budget and experience.
On the materials side, using greener products (for example, ones that are locally sourced, made from recycled content, or rapidly renewable materials, or certified) could be more expensive. This cost could be compounded by the scheduling challenges and delays created by using green, non-standard products if project team was inexperienced or the decision to build green was made too late.
On the labor side, there may be additional time burden of managing the construction site in accordance with green building principles, usually related to:
- Construction Activity Pollution Prevention
- Construction Waste Management
- Reused structures and/or recycled materials
- Construction IAQ Management Plan
For projects pursuing higher green goals, some advanced, innovative technologies can be involved and have big cost impact, such as onsite renewable energy generation, demand-control ventilation system, etc.
It should be recognized that both potential increases in hard and soft costs due to green specifications are coming down as green technologies, processes and materials become more widely available. Market competition also acts as a force to keep these costs down to reasonable levels.
Many empirical studies have been done to determine the cost of green building. In these studies, LEED certification (or some alternatives, such as Green Star or BREEAM) is often used as a benchmark for green. Then there are several methodologies to assess the cost premium of green:
Method 1: Comparing original budget to final budget.
This method should be used with caution, since the original budget was rarely adequate, and not all extra costs are due to green. Most of the studies that use this methodology report average green premiums in the range of 1%-2% to achieve a moderate level of sustainable design (for example, LEED Silver).
Method 2: Comparing green buildings to non-green buildings of similar type and use
Compare to other methods, this method requires you to make fewer assumptions of what you would have built or what it should have cost, but the challenge is to find a population of comparable buildings and the adjustment for time and location to bring the comparable buildings to a common base. Because of the data demand, this approach is not widely used.
Method 3: A point-by-point assessment of the cost premiums associated with LEED (or BREEAM, Green Star, etc.)
This method views most green features as additive to a baseline project. It often does not reflect design choices and trade-offs typically made during the design and construction process.
In all cases, the actual cost of green building will depend greatly on many factors, including building type, project location, experience of project team, certification target, and whether advanced or innovative technologies, usually expensive, are used. The studies demonstrate that sustainable design is within reach for most projects. Green goals should be established and integrated early as any other project goals. By good planning processes, buildings that are better for the environment and healthier for occupants can be delivered in a cost-effective way.
One of the first comprehensive studies, titled Costing Green: A Comprehensive Cost Database and Budgeting Methodology, was published in July 2004 by Davis Langdon, a construction cost management consulting firm. Focused on construction costs only, the study assessed the incremental cost of individual LEED credits, as well as the construction cost impact of various levels of LEED certification. The study included 90 non-LEED projects and 50 LEED-certified projects and found no statistically significant impact, with the conclusion that “the cost per square foot for buildings seeking LEED certification falls into the existing range of costs for buildings of similar program type” and “many projects can achieve sustainable design within their initial budget, or with very small supplemental funding”. A July 2007 update, titled The Cost of Green Revisited, studied 221 US buildings and arrived at essentially the same results. According to the report, “there is no significant difference in average costs for green buildings as compared to non-green buildings.”
How to minimize additional cost of Green Buildings?
Best practices from past projects include:
- Start early:
As with any aspect of the building program, a project’s environmental and performance goals should be established as early as possible, whether or not green certification is pursued. Green building goals should be seen as simply part of the building program, rather than something outside of the normal process.
As with any specialized project requirements, selecting design and construction teams experienced with green building certification will increase the odds of success.
- Applying Integrated Design Process:
Green building certification can be pursued with the conventional design-bid-build project delivery; however, the construction management approach, with the resulting earlier involvement of the construction team during design, is particularly well-suited to the integrated design process.
Certification programs like LEED and LOTUS encourage the full project team to collaborate to achieve the project’s performance goals. The most effective approach to certification is in fact to forget the points. When teams focus first on broader goals, such as reducing energy use or improving water efficiency, more integrated, cost-effective solutions can often be developed.
For effective process performance optimization, the first step is to reduce the loads (smart design), then to meet the loads efficiently (efficient equipment). Then, only after these have been accomplished, considering greening the residual supply required to meet the reduced loads (renewable energy, rainwater harvest, etc.). Green design is expensive when it only consists of adding expensive technologies to an essentially conventional project.
Quantitative analysis, such as energy modeling, is required to document performance for LEED or LOTUS certification. However, the results of this analysis can be used most effectively to inform the design process, rather than simply documenting performance after the fact. The Davis Langdon study recommends that energy and cost models be combined “to make a very effective decision-making tool, preferably early in design.”
Energy modeling can be used to understand where the big impacts are for a project type in a particular climate, allowing the design team to optimize the design. When leveraged in this fashion, quantitative analysis becomes a value-added tool for reducing a project’s cost of ownership.