How to Design an Energy-Efficient Building?
This can be achieved by thinking of the structure as a single organism. All its parts and interaction with the environment are interdependent and contribute to the organism’s overall function.
Back then in construction and architecture, facade systems are treated as separate components of the buildings. However, to achieve high efficiency and building performance, the facade should be actually integrated with the overall building design and function. It’s not a separate entity anymore. Due to their huge potential impact to energy use of buildings, facade systems now get more attention and require a thorough planning. This is to integrate them with the structure and environment as well.
How to achieve a high-performance facade system?
A facade is often thought of as a boundary between the external and internal environments of the building. It can also be viewed as a layer of protection against wind, sun, rain and other external elements. But perhaps the more accurate view is to think of it as a cell membrane (biological systems are amazing sources of inspiration). That’s because aside from protecting the cell from its surroundings, the cell membrane also controls the movement of substances in and out of the cell.
This is very similar to how facade systems work. Facades protect the buildings from outside elements while also “controlling” the flow of light and heat into the structures. It’s a protective layer and yet an essential one in allowing or limiting certain elements into the building.
For example, there are now innovative glazing systems installed in modern buildings that allow maximum visible light transmission while also interrupting heat gain or heat loss. This results to maximum daylighting (which is good for people’s mood and productivity) and lower energy use for artificial lighting, heating and/or cooling. This can be achieved by utilising a kind of glass that selectively controls which spectrum range will be allowed to enter the building. For instance, infrared rays (responsible for the heat) can be excluded while other spectral ranges will be allowed for daylighting.
There are even smart glazing systems that automatically adjust according to outdoor lighting conditions. This results to optimising indoor daylight performance (maximum sunlight coming into the building) and controlling glare (blinding brightness).
Many building facades also have incorporated double and triple glazing systems. Double glazing systems provide a “thermal break” which reduces heat transfer. To achieve higher thermal performance, triple glazing systems are used. Aside from reducing thermal conductance, these glazing systems also contribute to better acoustics performance. This is an excellent feature in noise-polluted environments and crucial in the proper function of recording studios, laboratories and other facilities that require minimal noise.
There are also “traditional” ways of blocking heat and daylight. For example, many modern buildings still have horizontal overhangs and vertical fins that physically and straightforwardly block the sunlight. However, this can affect exterior and interior aesthetics because of limited view opportunity and addition of “clutter” on the building surface.
Nevertheless, innovative glazing systems can be installed in both new and retrofit construction. As discussed earlier, the design of facades and incorporation of glazing systems should be a vital part of the big picture. It should be an integrated package with interdependent parts and systems (just like a single organism).
Aside from heat, light and sound, facade designers and engineers also pay attention to the following important factors:
- Orientation of the sun & Earth’s movement (how sunlight changes direction as hours go by)
- Day and night ventilation (e.g. reduced heating or cooling expenses)
- View opportunity (e.g. residential tenants want a nice view of the coast)
- Wind direction all year round
- Earthquake & fire safety
- Local climate conditions
All these factors make facade design and engineering more challenging. These variables are dynamic and their combinations can be unique according to each site and purpose of the building. Also, the changes in these variables can be erratic and unpredictable. Each month wind direction and local climate conditions might wildly vary. The design of the facade (and the building overall) should account for these possible deviations and changes.
Why energy efficiency is so important
40% of the world’s energy consumption is due to building energy use. Moreover, buildings are also a source of 33% of greenhouse gas emissions. Expect these numbers to rise even further due to urbanisation, increasing population density and progress. The outcomes could even be worse if there’s significant rise in the temperatures which can exacerbate cooling and air conditioning expenses.
That’s why from construction to utilisation of the building, almost everything should be geared towards sustainability and minimising environmental impact. It’s especially the case in designing highrises and other buildings that require a lot of energy to maintain and operate. Even a 1% reduction in monthly energy use is significant. Aside from cost savings, there will be less carbon footprint and lower environmental impact.
To achieve this, it’s crucial to focus on the few things that result to biggest impacts. For instance, if the building’s design is “smart” and high performance, long-term cost savings will be the result. It can start with replacing the facade (for retrofit) or properly designing both the facade and the building as an integrated package (for new construction).
There should also be a balance between the engineering requirements and architectural advantages. Both the design and function should work hand in hand to express the building’s purpose. For instance, the building should be of high performance (efficient energy use) while not sacrificing its architectural integrity. This is a huge challenge whether it’s a residential, commercial or government structure.
Accurate 3D models aid in easy visualisation of the structure once it’s finished. Aside from viewing the representation of how the building and facade will look like, 3D models would also allow us to better visualise the building’s relationship and “interaction” with the environment. As a result, preliminary designs could be modified or improved based on the future appearance of the “finished product.”
That’s about the aesthetic part but what about the actual performance of the building? How will we know if a certain design or material will result to the desired outcomes? Let’s also think about the cost because we’re always aiming for efficiency or achieving the same outcome with fewer resources.
To evaluate the future performance of the building, often simulations and mock-up tests are performed. Aside from evaluating and validating the facade’s design, these tests and simulations also allow engineers to detect flaws and problem areas such as water leakage and air infiltration. Facade engineers will also focus on the following:
- Structural loading
- Thermal cycling
- Impact safety
- Dynamic seismic performance
- Compliance with standards & specifications
There are parameters to be used and these should be selected according to Australian standards. Moreover, the test results should validate (or invalidate) the facade design, selection of materials and workmanship in the job site.
When it comes to selecting and sourcing materials as per the desired specifications, facade consultants also pay attention to this crucial part of the whole process. Often there are factory inspections to ensure the products adhere to standards and specifications. Factory inspections may include inspection of manufacturing design, initial production, raw material storage and quality control measures. It can be a random inspection for better accuracy and sampling. Facade engineers and consultants may also perform a final inspection prior to shipment of the fabricated materials.
An energy-efficient building for your organisation
High performance and energy efficiency can only be achieved through an integrated approach. From design up to validation (including product sourcing and logistics), every step of the facade design and construction should always be left to the experts.
That’s why here at CGS Facade Group, our team with international experience (Sydney, Melbourne, Singapore, Middle East, Macau and other locations) provides personal attention to each project. We understand that each site and project has its own unique challenges.
When it comes to design and construction of facade systems and building envelopes, CGS Facade Group is able to handle it all from the design up to the validation. We also handle factory inspections of the materials to be used to ensure quality. We even take care of the facade management so the building frontage will remain beautiful and sophisticated.
Contact us today and let’s discuss your vision about how your facade should perform and look like. We have an office at Suite 8.05, Level 8, 139-141 Macquarie Street, Sydney NSW 2000, Australia