In the heart of Observatory, one of Cape Town’s heritage buildings has become a space that future generations now call home. A space where old and new – quite literally – intertwine, Peak Studios student accommodation is part of Growthpoint Properties Student Accommodation Holdings portfolio, Thrive Student Living, and recently achieved EDGE – Excellence in Design for Greater Efficiencies – certification. The art deco design, dating back to 1938, flows smoothly into the new curves of the nine-storey building rising from the back of the original structure. Apart from housing 563 students, the project exemplifies resource efficiency and a sustainable way of living.
According to Cornelia Mey, EDGE auditor and sustainability engineer at Ecolution, the EDGE rating places resource efficiency front and centre. “Being more efficient is considered one of the biggest potential energy resources,” she says. Peak Studios is proof of that. “Resource efficiency is important to the team responsible for operating the building as well as the students who use it,” adds Grahame Cruickshanks, Growthpoint Properties’ head of sustainability and utilities. “The green initiatives ensure that it’s both cost-effective and reduces environmental impact.”
Face brick is used to pleasing visual effect on the curved exterior of the new building.
Designed with the resident in mind, this project achieved EDGE certification by exploiting efficiency. “The EDGE model takes into consideration who the building is aimed at, and what their typical usage patterns would be,” says Mey. You wouldn’t, therefore, use the same tool to rate high-income apartments and student accommodation.
Compared to the average of a 15%, this building’s window-to-floor ratio is 4% – reducing heat loss from the core of the building.
To achieve EDGE certification, the project must use 20% less energy, water and materials, than would typically be used in a similar development. A score of 40% on energy savings elevates the project to EDGE Advanced, and from there, projects can aim for a Net Zero rating.
Energy savings: 39%
Two big energy consumers in residential spaces are cooking and hot water – these areas are where Peak Studios demonstrated its biggest energy saving, despite not yet having an integrated solar energy system in place.
“You get your best results by reducing consumption,” says Mey. “That’s why it’s important to get those down as far as possible before you add solar photovoltaics [PV] to the system, to start compensating for additional elements.”
The largest portion of savings is attributed to the water heating system. “The heat pump system is much more efficient than conventional geysers,” she says. “The base case for the heating of water would have consumed 30kWh [kilowatt-hour] per square metre annually – now it’s consuming only 8kWh, reducing consumption by a third.” According to Mey, the fact that the building will use 41% less water also contributes to energy saving.
In addition, the building’s passive design also plays an important role in energy savings. Compared to the average of 15%, Peak Studios’ window-to-floor ratio is 4%. “While there are a lot of windows on the facade, the floor plan is quite deep, which reduces the amount of heat lost from the core of the building,” says Mey. Cruickshanks adds, “By taking an integrated approach to the facade design, the consultant team has ensured that the students who use the interior spaces are comfortable and receive enough natural light, but also that the building is performing in an energy-efficient way.”
Although there isn’t a solar system now, the roof has been designed to accommodate it in the future. Working alongside fellow GASS architects Piet Boer and Chris Bakker, project architect Leoné Wierenga says the team went the extra mile, particularly in regard to the design of a suitable hatch. “This was quite a challenge,” she laughs. “To future-proof the building, the hatch has specifically been designed in terms of its size, so that when the solar panels are ready to be incorporated, it’s accessible.”
Water savings: 41%
The secret to saving 41% of water in student accommodation? Low-flow showerheads and aerated basin taps.
Wierenga says all the sanitary ware used in the project are from Hansgrohe’s entry-level series, which affords a flow rate of only about 5 litres/minute – much less than the base case of 9.5 litres/minute. “All the taps and mixers are fitted with an aerator, to a reach of 5 litres/minute for the kitchen, and 3 litres/minute for the basins in the bathrooms, which allows control over the amount of water used.” According to Mey, to a lesser extent, the dual flush toilets also help with water saving.
Pipework from the previous building has been incorporated into the new building.
Some of the building’s design elements highlight attention to finer details. “In the courtyard, the main feature in the middle is a large portion of permeable paving,” says Wierenga. The goal, achieved with the help of the AECOM Civils team, is to reduce storm water run-off. “It just seeps in, and that’s very beneficial for the soil water and the civil systems of the city.” Moreover, all the landscaped areas make use of water-wise plantings and there’s a cap of 4 litres/minute on irrigation.
Material savings: 44%
From the project outset, one thing was made abundantly clear: any material that could be salvaged from the original building had to be used – much to the joy of the architects.
“The portion of the building that we did keep is the front, as it was heritage-graded,” says Wierenga. “It has an important presence on the road, and the greatest thing is to see the existing building with the added ‘life’ pumped into it after the new addition.”
Attention was turned to a chapel incorporated in the original building – owing to its art deco design, it was a relatively dark space. “It was clad in wood and we ended up having to break it open,” recalls Wierenga. This created a gap between the old and the new buildings, and now it’s a courtyard that floods light into the entrance.”
Nomamfengu Mbele, a sustainability specialist at Growthpoint Properties, underscores the importance of using existing infrastructure, fabric, and even the building’s orientation. “They say reusing [what’s available] is better than redeveloping on a new site, and it shows in the seamless certification achieved here.”
Although Mey says it wasn’t necessarily a determining factor in the rating, the upcycling aspect is noticeable – and important to the client’s representative, Manuel Maragelis. “He was very specific about trying to salvage as much as we could from the building,” says Wierenga. “We ended up with a long list of salvageable materials that the contractor had to remove before demolitions began.”
Materials for reuse included timber cladding from the original building’s chapel and office space, which can now be seen on the benches in some common areas, as well as the new office. Some of the pipe work and an old fire hydrant have also been retained, along with the previous buildings’ fire doors. “We added the doors to the study space to separate the open study area from the more private computer area,” explains Wierenga.
According to Mey, the biggest contributor to this score is the post-tensioned concrete floor slabs, which are much thinner than the base case. “They also have a lower steel bar usage, and because of the broad floorplan, fewer bricks were used there.”
The exterior makes good use of face brick, while the interior walls consist of perforated, 90mm maxi bricks. This also meant fewer bricks were utilised, and the decision to use different-sized bricks afforded an opportunity for the contractor to showcase their skills – using bricks that aren’t uniform on the same wall is not an easy feat. “[This was compounded by] the fact that [it has] a very curvy facade, which is not easy to build,” Wierenga says. “But in the end, it contributes to the success of the building. We were able to use much less material in creating the same space.”
Today’s efficiency – tomorrow’s heritage
The buck doesn’t stop here. “This is the first time most of the occupants would have left their family homes, and this sets a [benchmark] for them,” Mey says. “It normalises an efficient design and raises the bar of expectations for those just entering the property market.”
Another element Wierenga highlights is the use of smart meters – and Cruickshanks concurs: “With smart meters, you’re able to isolate some of your consumption patterns. You can monitor when you use electricity and what is consuming it.” In this way, a more conscious way of consumption is reinforced, and according to Mbele, the market is ready for it: “It’s exciting to see how resource efficiency is attracting financing! [Finance houses] are looking to see if portfolios are meeting specific Green Star or EDGE requirements, and that helps us embed certain principles within our developments that support carbon neutrality in the long term.”
