Developing both the body and the intellect

Compiled by Benjamin Brits

Paterson Park Sports and Recreation facility in Gauteng, is a multi-purpose complex comprising eight buildings – the main hall celebrating a heritage structure.

As part of the City of Johannesburg’s strategy to meet their demand for new social infrastructure, the Johannesburg Development Agency (JDA), has completed the construction on this project that will benefit and enhance the the lives and lifestyles of the residents in the community of Norwood, Orchards, Orange Grove and the adjacent neighbourhoods.

The project handover took place in December 2020, after over a five-year period of delays due to contractor changes that resulted in a challenging stop-start type development, and consequent ‘canvass to complete’ for the final appointed teams.

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The idea behind the recreational facility is to provide a safe space that facilitates the development of fundamental skills, such as reading and writing partnered with various physical activities and health, to stimulate growth and development in the community.

The land available for new social infrastructure within the Louis Botha Corridor (where the facility is located) is limited and therefore existing clusters have to be optimised and upgraded for current and future use. Patterson Park was already a well-maintiained area and therefore was ideal for the upgrade and expansion.

This facility is one of the latest completed projects by the JDA, adding to the more than 600 implemented projects across all administrative regions of the City.

After the various project delays and contractor changes, the JDA appointed GVK-Siya Zama Construction in mid-2019 for the completion of construction of the facility, which they have seen through with commendable quality.

As part of the facility upgrade, an old club house in Paterson Park – a heritage building – was commemorated through a special mural on the side of the new recreation centre’s main hall that overlooks the site where the original structure once stood. What was retained of the heritage building was the original foundations and four pillars.

An important aspect of this project for both the JDA and City alike, is not only the safety and security of the facility, but also a sense of ownership from the community, ensuring that the facility will be used by future generations too. Further, reducing crime in the youth by allowing them to express themselves and learn various skills through what the facility has to offer.

The main hall’s decorative design celebrates the history of the heritage building it looks onto. The foundations and pillars were the only elements retained. Photo by © GVK Siya Zama

Project features

The client brief was essentially the development of a multi-functional recreation park to cater to the communities’ recreational needs through various sports, learning and creative opportunities.

The facility is equipped with:

• near-olympic-style swimming pool and adacent splash pool (with grandstand)
• full size soccer field (with grandstand)
  two smaller five-a-side fields
• two tennis courts
• multi court and a basketball court (with pavilion)
• enclosed multi-functional gymnasium
• fully equipped gym with power circuit
• state-of-the-art library (printed and electronic access)
• craft centre (to facilitate artistic expression)
• amphitheatre (for community-organised shows, presentations and recitals)
• administrative building
• various kitchen areas
• medical facility
• security houses

The project also includes a water reclamation system where all of the excess water and rainwater that gets harvested is collected into a huge storage tank located between the swimming pool area and outdoor football field. This is then used to irrigate the sports fields.

Further a 112kW solar photovoltaic (PV) system was installed, covering the entire roof of the gymnasium. The energy generated from this system feeds a 120kWh battery bank and is linked to supply electricity to the library, admin building and also directly runs the pool pump system. The battery bank is able to supply the equivalent of 300 Amp hours to these facility builings.

HVAC elements

Carrying the project through to completion, Thembakele Consulting Engineers (TCE) was appointed to handle and manage the remaining elements, including the mechanical (HVAC).

TCE were appointed as the civil, structural, mechanical and electrical engineers from the outset of this project. In the execution of the project, this multi-disciplined professional engineering practise was responsible for all engineering functions of the works.

TCE’s civil engineers designed and oversaw the bulk earthworks, layerworks, foundations and construction of the various buildings, stormwater management and drainage systems of the project. Their structural engineers dealt with the structures and finishes, whilst their mechanical and electrical engineers added the “unseen” value elements of the works.

Achieving the best balance between cost of operation, cost of installation, future development and maintenance were all considerations given to the final design layout applied.

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The majority of the air-condition installation comprised various unitaries in the form of split wall units, cassette units and some hideaways. This was to accommodate the numerous small areas and offices and also the number of occupants in these areas at any time.

Ideally, TCE would have liked to see an installation of this type move more towards the variable refrigerant flow (VRF) technology, however, for one unit at a time being used, it would be economically unsound. TCE therefore had to choose a solution that would be balanced between practicality and utilisation.

“You cant handle something like the Coronavirus without understanding it and how it spreads.”

What influenced the development and the design of the HVAC system in the gymnasium was the fact that this area could be utilised for a basketaball game with 150 spectators, or could be utilised for a seven-a-side hockey game with only 40 spectators.

The supply and return air ducts to the gymnasium located at the plant space area. Photo by © RACA Journal | Benjamin Brits

Dealing with this differential in heat load, and the load to accommodate the return air temperature, these parameters proved suitable for a packaged VRF system that was installed with a multi-stage cooling function and VRF control of capacity load-gain from 10% to 110% (the system can actually utilise upto 110% of the calculated load in the event that the conditions of use require this).

This project required an energy efficient rooftop unit and HC Heat Exchangers therefore supplied a hybrid rooftop unit, which includes the latest VRF technology. The unit was an excellent choice to meet the project demands of varied heat profiles coupled with accurate capacity control- enabled by the multiple variable speed compressors of the Hitachi VRF condensing units. The part load efficiency of these VRF units offer lifetime savings as they are designed to accommodate the varying load profiles found in our local and international markets.

A further benefit of this design was the reduction in start-up power required which also ensures continuous electrical savings. Being part of the solution to HC Heat Exchangers client’s needs, a particular example of this was the need to accommodate the limited plant room space available on the allocated deck, without compromising performance. Working side by side with the contractor and consultant they were able to design a purpose-built compact hybrid unit to match both the capacity and space requirements.

Originally, considerations had been towards a chilled water system, but because of the long lead time required in getting chillers into the country and the additional electrical load of these units, TCE had to look at greening the installation as far as possible and thus partnered in developing the packaged VRF system. This newly-developed packaged VRF system has since become an accepted system for other installations of the same nature, as well as specialised applications in Africa.

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The fabric ducting into the gymnasium area (supplied by Fabric Air), something seen on the international level for more than 30 years is not very common in South Africa, and is in fact a brilliant product for this application according to TCE because it produces a constant cooling system right the way through the large open auditorium and the return air is ducted back directly to the packaged unit that is mounted on the high-level service platform deck at the back of the building. Both the return air and fresh air to the gymnasium are sterilised through the use of UV-C lights mounted within the packaged unit.

All ventilation systems for the ducted units and toilet extraction was completed according to the requirements of ASHRAE airflow guidelenes. The ducting was manufactured strictly in accordance with SMACNA guidelines for the flow and distribution of conditioned air within the occupied spaces. (SMACNA is the Sheet Metal and Air Conditioning Contractors’ National Association that is an international association of union contractors. SMACNA standards and manuals address all facets of the sheet metal and HVAC industry, from duct construction and installation to indoor air quality, from energy recovery to roofing, from solar energy to welding.)

Project challenges

As you may have experienced, picking up the pieces of a stop-start project is not an easy feat as there are many loose ends to be identified and managed – not to mention a limited budget. One such element that TCE had to navigate was the appointment of the prior HVAC contractor. This original HVAC sub-contractor was appointed by the first main contractor and assumed that their engagement would be automatically validated by GVK Siya Zama when they were appointed as the final main contractor.

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To TCE’s disappointment, this prior contractor could not provide current gas handling and recovery certification. Nor could they demonstrate a professional knowledge of the differences between various refrigerant gases and the protocols applied to their application. When it comes down to these important fundamental elements, TCE has very specific requirements for the contractors they appoint (as should all consulting engineers) and thus had to seek out a more competent HVAC contractor.

Worth including here, TCE notes that the Montreal Protocol on Substances that Deplete the Ozone Layer was developed and adopted to establish a worldwide awareness of the fragile state of our environment. The terms of this protocol state that, “Parties shall take appropriate measures in accordance with the provisions of this convention and of those protocols in force to which they are party to protect human health and the environment against adverse effects resulting or likely to result from human activities which modify or are likely to modify the ozone layer”.

The intent of this Protocol is to specifically assist in the reduction of the depletion of the ozone layer through the use of ozone-friendly gases.

The Kyoto Protocol was then established to support the Montreal Protocol and South Africa is not ony a signatory to these Protocols, but also a signatory to all of the ratifications thereto, binding the country by international convention to maintain the prescriptions and requirements. Not knowing or abiding with the intent or application of the content of these international treaties is considered negligent.

The gymnasium posed the most significant challenge in the HVAC design for this project, purely due to its sheer size – a monstrous void that houses various possible indoor activities and along with that – variable occupancy. Attached to the gymnasium itself is something similar to a minuature version of a gym or health club circuit, and the HVAC system installed there needed to run independently on its own AC system when the main gymnasium was not being used.

Technical difficulties that needed to be addressed in this project, and specifically under the changes in regulations imposed by the global Coronavirus pandemic that has caused severe issues with health and indoor air quality, in June 2020 the South African government issued a gazette (43400) that specifies all return air must be filtered through high efficiency particulate filters (HEPA) which provide a 95% effective filtration at 0.3 microns. A custom sterilisation system (described above) was therefore designed and supplied to meet these requirements in the gymnasium.

Unique elements and efficiency

The custom system that has been installed in the gymnasium makes it one of the most advanced in the country – there is only one other system like this that is operating at a hospital in Klerksdorp in the North West Province, with the same sterilisation methodology – pressurised air coming into the system from a circulatory, and exhaust air being returned to the atmosphere (conditioned through the addition of the UV-C lights).

Having conducted a significant amount of research around the Coronavirus from sources around the world including Japan, Finland, Switzerland, Belgium, Ireland, Canada, USA and Germany about how the virus spreads, TCE obtained evidence from laboratory testing that indicates that UV-C treatment of air in a circulatory application has been shown (in laboratory) to be effective in encapsulating the SARS-COV-2 virus (essentially meaning this process restricts the reproductive process of the virus).

The rationale for inclusion of the UV-C solution was due to the fact that although HEPA filtration is effective for particle sizes of 0.3 micron, various research has shown that the coronavirus is as small as only 0.1 micron therefore passing through a HEPA filter. The UV-C solution was therefore a must to include in the system.

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The benefit and thought process of re-cycling air through a sterilisation system such as installed at this project is informed by available laboratory testing that indicates that every time the air passes through, you get further sterilisation, eventually resulting in up to 90% of encapsulation of any virus (thus greatly reducing the risk of spread). TCE also rightly stated that you can’t handle something like the Coronavirus without understanding it, and further how it spreads.

On the energy efficiency aspect, with unitary equipment TCE notes that all you can do is hope that the users will be considerate and switch the equipment off after use. Ideally occupation sensors for lights and energised cooling circuits would have been preferable but this became too expensive to fit within the remaining budget after all of the prior contractor changes and depleted balance of budget. 

Sources: 

• Thembakele Consulting Engineers
• Johannesburg Development Agency
• New Urban Architects and Urban Designers
• HC Heat Exchangers
• GVK Siya Zama
• Tesla Electrical

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