SA Roofing Magazine,
July 2012.
The former Davenport Centre, now called Davenport Square, recently underwent a R21 million revamp that has completely converted the outdated Glenwood shopping centre into a modern and inviting complex that is simply delightful to visit. The highly talented and acclaimed Durban firm Sphere Design & Architecture spearheaded the architectural design of the project. Here they share insight into the elements that made this transformation so successful.
SA ROOFING:
All round congratulations to Sphere Design & Architecture on your stellar architectural design of the recently revamped Davenport Square. What used to be called an old, drab looking shopping mall has undergone a complete makeover into a bright, stylish and trendy complex. Can you share with us more about your brief for the project?
SPHERE:
Thank you! Refurbishments are a challenge, but there is much reward in comparing the before and after photos when the job is done. As with most projects, budget was a key driver regarding how far we could go with the upgrade, we had to ensure that maximum aesthetic and functional improvement was achieved. The main strategy was to simplify the look of the shop fronts to all the stores, and use increased lighting to improve what was a dark main corridor. New ceilings and floor finishes and uniform signage criteria ensured that the modern look was carried throughout the mall. The exterior of the mall also received a “face lift” with a new colour palette and feature towers to highlight points of entry. Improved relationship with the street was achieved with the addition of a unified restaurant block along Brand road.
SA ROOFING:
What was the most challenging design aspect you faced?
SPHERE:
We had to ensure that design decisions took into account that the building was to remain fully functional as a shopping mall for the entire duration of the project. This influenced how we designed various details to cause minimum possible disturbance to tenants and shoppers. It was a constant challenge!
SA ROOFING:
Were there specific factors that influenced your design or the execution of your plans?
SPHERE:
The client is very concerned that all their buildings seek to employ energy saving methods and this was an important factor, for example, seeking to balance the energy consumption of the mall lighting with the required lux levels for a mall. Energy waste was reduced via improved insulation and water saving technologies.
SA ROOFING:
Did you use a BIM (Building Information Modeling) process for this design?
SPHERE:
BIM was not used for this specific project.
SA ROOFING:
One of the most significant changes to the complex is the impressive new food court atrium. Please tell us more about the concept behind the dome shaped roof.
SPHERE:
The history of the building is that it was once designed to be an open mall, which after some years was closed over. The impressive steel dome structure was in much need of a refurb, and remnants of mall decorations were not doing much to highlight the beauty of the engineering. Another big problem was the intense heat gain that this area experiences during the summer months. As such, we had a framework with which we could work.
SA ROOFING:
Were there specific factors that influenced your selection of roof sheeting and other cladding, as well as the roof support system (trusses) used on this structure?
SPHERE:
The existing steel trusses were in good shape apart from some rust patches, which we cleaned up and re-painted. We looked at various roof covering options, but the flexibility of the IBR sheeting proved the most economical solution. Heat gain was still a big issue, so we decided to employ a sandwich detail consisting of an externally cranked IBR sheeted roof under which an appropriate insulation material was fixed between the existing trusses. Finally, below this, an additional layer of cranked IBR sheeting was used as the “cladding” the underside of which was powder coated white to amplify the light, clean look of the mall. We then added a combination of whirly bird and strip roof vents to assist with the cooling of the atrium space. The combination of the vents and insulation has made a noticeable difference to the reduction of heat gain to this area, and both are passive cooling strategies which are great alternatives to mechanical ventilation options.
SA ROOFING:
What is the significance of the upper bulk heads that are used throughout the passageways of the complex?
SPHERE:
The existing mall construction incorporated deep beams at regular grid intervals, and these were visible along the length, using coffered spaces between the beams. The beams are thus concealed by the parts of the ceiling that drop down between the illuminated coffered “boxes”.
SA ROOFING:
The ceiling detail is quite remarkable. How did this design element come about?
SPHERE:
We wanted to design a bright, continuous ceiling that incorporated different lighting options to create a modern effect. The mall ceilings extend into all the shops by a metre to accommodate improved shop front lighting and a consistent design aspect to every store, despite the various store offerings, thereby linking all the stores together.
SA ROOFING:
Given the locale, did you have to work around any extreme weather conditions or considerations in terms of both architecture and engineering?
SPHERE:
The humidity of Durban is always a key design concern. The grade of lighting materials, stainless steel and galvanising is cognisant of this.
SA ROOFING:
Still with weather in mind, and particularly high winds, can you tell us what fastening systems were used on the roof, and if these were locally sourced?
SPHERE:
We consulted with our roofing contractors, M.J. Cheater & Co, in this regard and they provided us with the recommended specification.
SA ROOFING:
Can you tell us more about the insulation materials used?
SPHERE:
The insulation product that we used is called Isover “Factorylite” 50mm. “Factorylite” is manufactured from high quality non-combustible flexible Glasswool insulation with aninert binder, which makes the product lightweight, safe and resilient. “Factorylite” is faced on one side with either a re-inforced foil, white metalised foil, or black metalised foil. This product has both thermal and acoustic properties. It is suitable for use in humid climates which was important given the location of the mall.
SA ROOFING:
Was the roof cladding profiled on site and if so, what thickness coil was used and why this particular brand?
SPHERE:
The product is Safintra SAFLOK 700. The cranking radius was 4000mm. The sheets were cranked off site and transported to site where they were assembled and fixed to the steel dome truss structure.
SA ROOFING:
What is the highest point of the domed roof?
What safety precautions needed to be taken to work at this height?
SPHERE:
The highest point is approximately 9000mm from the internal finished floor level. Safety was a big concern as the area below the roof was in constant use by the shoppers. Even so, scaffolding was erected and safety officers oversaw the process and ensured that there was ample warning signage in the vicinity.
SA ROOFING:
Any closing thoughts on what made the revamp project so successful, ensuring a more inviting and enjoyable place for Glenwood shoppers to visit?
SPHERE:
The project team worked very well together-and definitely makes for a smoother construction process. The client was also concerned that the tenants be informed of their various construction stages and accommodated where their requests were within reason. As such, the team worked hard to maintain the balance between a great finish within budget and happy tenants and shoppers. Our client is very happy with the final result, and that is important to us.
SA ROOFING:
What has the shopping community’s feedback been?
SPHERE:
We have had a lot of positive feedback, many shoppers and tenants have expressed their gratitude for the “new” centre and hearing their approval makes all of our effort worthwhile.
