Case Study: Sports Centre (UWC)

Jo Noero architects commissioned Structatherm Projects to carry out a rational design for a new sports centre at the University of the Western Cape. The Sports centre is an extension to the existing sports facility adjacent to the existing stadium.

The building houses a gymnasium, administration offices, change rooms, bar, restaurant, a sports hall and medical suites. The building was designed to make use of natural daylight with a glazed external west facing wall and a large portion of the roof over the gym and restaurant covered with skylight.

At first glance the design concept appeared to be counter intuitive to standard energy efficiency design principles. There was a window fenestration to net floor area ratio of over 50% and more than 50% of the roof was covered with skylights. The architects had however carefully thought out detail and mitigating design solutions that helped contribute to energy efficiency which could only be considered using a rational design. After the energy baseline usage was established, fine tuning recommendations brought the building into compliance with the regulations to ensure that the operation of the building would be thermally efficient.

The architects designed a breezeblock wall outside the offices to provide shade from the low west sun. The blocks were orientated so that maximum shade could be provided while maintaining views.

A double concrete slab was designed for the floor for noise reduction and the void in the floor was used for HVAC ducting with vents positioned in the floor of the gym

The Sports hall was designed to be fully covered but partially open to the elements. It was therefore possible to exclude this area from the calculations.

The roof of the gym is made up of a series of concrete U beams which contain the gutters and support multiple smaller pitched roofs. The Southern portion of the roof contains a skylight with a tinted polycarbonate cellular sheet thereby reducing the solar heat gain, and the northern part of the roofs contain a standard steel pitched roof with insulation

In order to bring the building into compliance the following recommendations were implemented.

  • Roofing- A 16mm tinted poly carbonate cellular roof sheet was specified to provide sufficient conductance and SHGc values while it still allowing visible light. The roof light area was reduced to 103 square metres.
  • Fenestration-the glass in the windows was changed from clear glass to low E glass in thermally unbroken frames to reduce the solar heat gain. The shading provided by the breeze block wall was utilized in the calculations to reduce SHGc
  • Walls- standard cavity wall construction was used without insulation.
  • Lighting- All light fitting were specified using new technology fittings- T 5 fluorescents fittings, compact fluorescent fittings and LEDs. Day-light sensors were used to reduce lighting levels when natural lighting levels allow.
  • Hot water- An efficient heat pump was specified to heat the existing hot water tanks. All resistive element heaters were removed.
  • HVAC- the required levels of HVAC was achieved by installing a direct expansion converter, reverse cycle, variable Refrigerant Volume heat pump of 140kW cooling capacity.