Building sustainable, green buildings is not a simple task, especially when aiming for Green Star ratings or other certifications. Selecting materials and products for green building starts with setting actual performance targets.
Just as one green building doesn’t make a green city, merely having solar photovoltaic (PV) panels on the roof also doesn’t make a green building.
While simple interventions such as solar PV and solar heating systems or double glazing will increase a building’s energy efficiency, there are many other categories of building construction in which to score additional green points. The Green Building Council of South Africa’s (GBCSA’s) Green Star South Africa rating system, like others from around the world, provides a range of “green measures that can be used in the design, construction and management of building to make it more sustainable”.
Set actual targets
To implement these green measures, green building consultants, Solid Green, says it is important to set specific targets upfront.
“Often people want an energy-efficient building, but they don’t define what that means. For us it may be a completely different target than for an electrical engineer. Without setting targets with measurable benchmarks the professional team is not able to give you an energy-efficient building,” says Marloes Reinink, founder of Solid Green.
Her colleague, Chilufya Lombe, a mechanical engineer with extensive experience in performance and accreditation modelling for sustainability projects, explains that to set targets, one has to have a benchmark.
“In South Africa, we’ve got the SANS 10400 building code, which is not a very challenging standard in terms of green building, so we look at with what percentage we can improve on the standard, generally starting off on about 50%. We work with actual numbers based on factors such as climate. And because there is published data from around the world, one can make comparisons with other buildings,” he explains.
Going for gold
With the announcement of the World Green Building Council’s (World GBC’s) “Advancing net zero” project, which aims for all new buildings and renovations to be built net zero, starting in 2030 and 100% of buildings being net zero by 2050, achieving this target has become the ultimate goal.
In support of this initiative, the Green Building Council of South Africa (GBCSA) has committed to employing a net zero/positive building certification scheme by 2020.
Net-zero refers to buildings which are either “net-zero energy” or “net-zero carbon”.
• Net-zero energy buildings are highly efficient buildings which consume net-zero energy (on an annual basis), meaning all the energy needed to power the building is generated through on-site renewable energy.
• Net-zero carbon buildings are buildings which produce net-zero carbon emissions (on an annual basis). The definition of zero carbon varies across countries and schemes, but can include an element of carbon offsetting.
For a building to really achieve such high targets, the ideal is to optimise the design from the get-go. “Architects should consider the impact of their designs and start by determining the environmental performance of the building. If one gets the passive and functional design elements right – things like orientation and the facade – then one won’t later on have to add expensive shading, glass or cooling systems just to make the building comfortable,” states Lombe.
“Clients often want views and natural light, but if glare and thermal comfort are not taken into account, the blinds will be drawn most of the time. The right size windows have to be put in the right places and this type of analysis is not always done,” he adds.
“Or, if one starts too late, one may just miss some easy green credits because the project would be too far along to make changes, leaving one with credits that are more difficult or expensive to achieve.”
It’s not always that simple
A green start, according to Reinink, can sometimes be hampered by the process though. “We find that even though many project teams realise the value of input by green consultants right from the beginning, it all depends on the process.
“For example, when it comes to commercial developments, the space needs to be sold before the developers can commit to pay anybody, so the first thing is to ask the architect to draw up some pretty images in a very short time frame. The architects can’t involve many other parties since there is no guarantee that the project will go ahead. Once it is sold and the project continues, one can’t make major changes and has to work with what you have. This is just the nature of construction,” Reinink explains.
“Also, no two buildings are the same, so what was applied on one project might not apply to the next. Therefore it is important for architects to understand what they are doing and interact with other professionals. Just as we don’t know everything, it is important for other members of the project team to acknowledge that they need input from other professions to come to the right solution and products,” she states.
Many things to consider specifying products
The embodied energy of materials is an important consideration for comparing options such as timber, steel and concrete, but data is not always readily available in South Africa, nor is it easy to know what to take into account and what not.
“It depends on the products you are looking at,” says Reinink. “The green aspects you look at for insulation are different from the green issues you look at for timber applications, for example. You need to be really aware of what you are looking at when considering materials.
“It is almost like the PVC vs aluminium discussion,” she continues. “To manufacture PVC toxic emissions are released in the atmosphere, but then it lasts forever, doesn’t discolour etc. The manufacturing of aluminium requires a lot of energy, but often has a high recycled content. So there are always things that you have to understand and weigh up against each other before making the decision. It isn’t straight forward at all,” she explains.
Reinink further says that green labels can play a valuable role as long as they are objective and transparent in providing information about what they are actually labelling and the results.
Do these three basic things
Having been involved with sourcing green products for Google’s Johannesburg office interior, which was awarded a five-star Green Star SA Interiors certification from the GBCSA and won the International Green Interior Award 2015, Reinink says it was interesting to see how far they could go.
“But in the end it comes back to the basics,” she says. “Try to reuse as much as possible. Get products with as much recycled content as possible, get it from local suppliers and make sure it was manufactured locally. When you do these three things, you are already on the right track when it comes to green.”
But sometimes, even having an appropriate product might not count towards certifications if not proved. “With timber it is always very difficult,” Reinink points out. “While most timber in South Africa is FSC-certified or comes from an FSC-certified forest, one needs chain of custody certificates of every single person who handled the wood for GBCSA or LEED certification, which is not always available. This is where the team just has to make a call and accept that it is better to have a piece of FSC timber than not, even without getting rewarded for it.”
There are also times when the client wants something, even though it isn’t the greenest option, and according to Lombe, this is where one just does the best to make it as green as possible. “People sometimes think that because you have a green building, you can’t do certain things. Or if the building is orientated incorrectly, that you can’t have a green building,” he says.
“But you just have to mitigate it or come up with ways to improve the performance.”
Reinink adds that architects shouldn’t feel that it is their responsibility alone – they have to use the team. “On the Google project it was a collaborative effort between us and the architects to get the materials right. They told us what they wanted and we gave them options that met the criteria.”
Don’t stop once the building is completed
According to Lombe, many examples exist of green buildings not being managed well from an energy and water perspective since the way in which the building should operate is not properly communicated to the people managing or occupying the building. In addition, many developers and building owners don’t see the benefit because they don’t track the building’s performance.
“Most places don’t have any data on the performance of the building and often buildings are already performing better than thought. But it is much easier to convince building owners that their planned HVAC is double than what they need if you’ve got data showing the energy use of the building. Even ones that put in metering don’t monitor or interpret it the way it is meant to be,” Lombe states.
Prove the value
This is an important step since the proof is ultimately in the pudding. At a time when rental deals are not signed on a weekly basis, it is even more difficult for developers to get tenants to pay a premium for an energy-efficient building of which they can’t guarantee performance.
“And it will probably be worse for net-zero buildings,” says Lombe. “With developers already feeling that energy efficiency is something they pay for, but the tenant enjoys, and it being very difficult to monetise the saving in terms of a rental premium on Green Star buildings, the only way developers will create a net-zero building and spend the extra money is if they have a client who asks for it or if they can work some sort of return into the rental agreement.”
Feedback on green investments
Case studies are one way to prove that investments in energy efficiency and alternative energy sources not only save energy, but also provide an attractive financial return for building owners.
Clay Nesler, VP of global energy and sustainability for the building efficiency business of Johnson Controls, points out that in 2009 the Empire State Building in the United States embarked on a project to reduce costs, increase real estate value and protect the environment. In 2011, the building beat its first-year energy-efficiency target by 5%, saving $2,4 million. The following three years saw the programme generate a total of approximately $7,5 million in energy savings at the landmark building.
The multimillion dollar investment in greening the building is projected to save 38% in energy consumption, not only saving money for the building’s owners, but also for the building’s tenants, who agreed to build out their office space to high-performance standards.
The 2016 Johnson Controls Energy-Efficiency Indicator (EEI) survey of more than 1 200 facility and energy management executives in the United States, Brazil, China, Germany and India indicates that as many as 72% of the organisations surveyed anticipate increased investments in energy efficiency and renewable energy over the next year. It also pointed to a lack of funding, insufficient payback, uncertain savings and a lack of technical expertise as the most significant barriers to investment.
The cost concern
Although South Africa didn’t form part of the survey, Nesler says there is a similar perception in South Africa that investing in green buildings is prohibitively expensive.
“While it can be costly, the cost savings will usually more than make up for the expenditure over time and subsequent to the payback period, the savings add directly to the bottom line,” he states.
“Over and above the cost saving and contribution towards a more sustainable environment, there are multiple additional benefits to energy-efficient buildings, such as the positive effect on a business’ brand and reputation with investors, customers and employees. There is a feel-good factor to knowing that a business is concerned with the environment,” Nesler points out.
The real green premium
Local research undertaken by the Cost of Green Building Study Committee, which comprised selected members from the GBCSA, the Association of South African Quantity Surveyors (ASAQS) and the University of Pretoria (UP), shows that building green in South Africa costs on average only 5% more and can be as low as 1,1% more than conventional building. In addition, since 2011 green cost premiums appear to be declining.
Certification date – green cost premium (%).
Year Minimum Average Maximum
2010 3,6% 3,6% 3,6%
2011 6,8% 8,3% 11,7%
2012 2,7% 8,2% 12,2%
2013 1,7% 3,5% 14,2%
2014 1,1% 6,6% 10,2%
The study points to a maturing of the South African green industry over time. Since 2011, green cost premiums appear to be declining.
The study includes cost data on a total of 54 Green Star SA office buildings, certified through the GBCSA’s Green Star SA – Office v1 tool up to the end of 2014.
As would be expected, the green cost premium increases with the Green Star SA rating, with an average premium for a four-star Green Star SA rated building being 4,5%, going up to an average of 10,9% for a six-star Green Star SA rated building. Other factors influencing green building costs are location, construction area, base building cost, tenant mix, vertical facade-to-construction area ratio, rating type (Design or As Built) and certification date.
“It all comes back to the importance of an integrated design process,” says Reinink. “If that happens right from the beginning, green building doesn’t have to come at a premium. Yes, that extra step to go to a six-star or net-zero building might cost more. But we often forget that if design elements, such as shading, are changed after the fact, then the cost is easily double what it would have been if it was planned from the beginning.”
Full thanks and acknowledgement are given to Solid Green Consulting, www.gbcsa.org.za, www.worldgbc.org and Johnson Controls for the information given to write this article.
Caption: One of the chairs in Google South Africa’s head office that was upholstered with material from jeans that were collected from staff members.
Photo by Graeme Wyllie, www.graemewyllie.com