Comvita Warehouse in Paengaroa

Hive of activity - BY MARY REAN, published in Rooflink Magazine, Spring 2019. 

Acknowledging the company’s core business of producing bee products, the brightly patterned new Comvita warehouse in Paengaroa is designed to resemble a collection of large, colourful beehives.

For Comvita, sustainability was a key part of their new premises, as a reflection of the company’s products – natural health products made from sustainably sourced raw materials – and its philosophy of helping people to be well and connected with nature.

The purpose-built 3500m2 East Wing warehouse on the company’s seven-hectare site was sustainably designed by Jigsaw Architects in Tauranga, and sits alongside its existing head office and tourism venture, Experience Comvita. Within this new $11.7m building is storage space for the company’s natural health products, a new honey sampling room, and covered outdoor work areas for loading and unloading trucks.

Chief Executive Scott Coulter says the completion of the East Wing is a significant milestone in the company’s growth journey, which started 45 years ago when co-founder Claude Stratford began making natural health products in the basement of his family home with his business partner, Alan Bougen. “We now have a purpose-built and sustainably designed warehouse to store our world-renowned honeys, and to support our global logistics,” Coulter says.

Sustainable features include the Bay of Plenty’s largest solar panel installation, enabling the building to generate enough energy to power 53 New Zealand households. The temperature control system in the building uses cool, night-time air during the summer months to maintain a desirable temperature. Fitted through the premises are LED lights that should reduce onsite energy consumption by 25,000kW annually.
Additionally, more than 65% of construction waste from the project has been recycled. Waste water is treated onsite using environmentally friendly practices and is used to irrigate a community garden that is open to local residents and supports 40,000 native and bee-friendly plants. Local construction company Marra built the warehouse, and civil and drainage work was carried out by Higgins.

Central to the design of the new warehouse is the roof and wall cladding, which uses Kingspan panel systems. The construction schedule required that the roof and external walls were erected first. The enclosed environment meant that the concrete could be poured and finished to achieve a very flat floor surface. This enabled the high-reach turret trucks to work in the narrow aisle racking configuration.

Brad Harkin of Harkin Roofing, whose company supplied and installed the 3600m2 roof, as well as external and internal wall cladding, says the roof design was straightforward, apart from the fact that Kingspan insulated panels (KS 1000 RW) were specified rather than a more traditional material like long-run steel. However, there was a very valid reason for this decision. Using insulated panels for the walls and roof of the warehouse ensures the temperature inside the building can be maintained at a constant, warm level, important when the product being stored is honey.

Each Kingspan panel measures 11m long by 1m wide with a 100mm core thickness, and weighs 120kg. “These large insulated panels are installed in quite a different way to a traditional iron roof, and the impact on the interior of the building is obviously very different too. With these panels, it is possible to maintain a constant temperature inside the building, whereas corrugated iron cools down at night and heats up  during the day.

Kingspan has a high R value so it stays at a constant temperature,” Harkin says. Installing such large and heavy panels added complexity to the project. Harkin Roofing used a new system to them to get the panels from the ground to the roof without damaging them. “All the panels were installed with an 80-tonne crane and a cladboy – a suction lifting device that is charged up overnight and is attached to the crane. Each panel can be lifted into place so there is no manual handling of the panels. Then a couple of guys on the roof screw each one into place,” says Harkin.

“At 120kg, there is a real risk of damage to the panels if they are being moved around, so using the crane and cladboy substantially reduced this risk,” he says. “This technique adds some cost and a bit more logistics to managing the project. We need to keep a close track of how many panels are installed each day to ensure we are keeping on schedule and don’t need the crane on site for any longer than necessary.”

But, on the other hand, this technique reduces the number of roofers required to work on the roof and Harkin says he really prefers it, "because there is less chance of damage to the panels when they are lifted straight up and into position. Also, such large, heavy panels are very awkward when they have to be lifted manually.” Harkin says the Comvita warehouse was the first job where they have used the cladboy, and it was so successful the company has now bought a second one.

The external walls, which are a key design feature of the building, use Kingspan horizontal wall panels (KS 1000 AWP) from the architectural range. These 1m-wide by 9.8m-long panels are applied to the building in a selection of different colours reminiscent of stacks of beehives  sitting in a field.

“One of the biggest things about the project was the use of coloured panels for the walls. They are non-standard, so Kingspan had to do special customised runs to produce the various shades of blue, pink, red and yellow specified by the architect for the Comvita building.
“The colours also made installation a bit trickier. The guys had to make sure they put the different colours in the right locations according to the architect’s plans and, logistically, we had to ensure we ordered enough panels in the various colours. There was a nine-week lead time from Australia, so we had to be extra vigilant to ensure panels weren’t accidentally damaged during installation. It wasn’t possible simply to
order more panels to be delivered, and we couldn’t have extra panels in all the different colours sitting around the site, just in case.

With a whole white wall, it’s not such an issue,” says Harkin. As with the installation of the roof, Harkin Roofing used one of its smaller 10-tonne cranes and the cladboy to lift exterior panels into place, to minimise the risk of damage. An advantage of Kingspan’s exterior wall
panels is that there are no exposed fixings – everything is secretly fixed to present a clean, unmarked finish, with each horizontal panel fixed in place and the next one fixed over it.

The panels are then joined on the portals with flashing details, and cracked corners, supplied already formed, are used instead of traditional flashings, and the panel itself forms the corner. This system, says Harkin, results in a building with a much cleaner and neater appearance, but it can be more challenging to install. Work starts at one corner of the building and the wall is set out from that point, so it’s essential to ensure the corners are right before moving on.

Each external wall on the Comvita warehouse is 12-panels high. “With this external Kingspan product, you cannot replace panels once they
are installed, and if a panel is damaged during the building process, the whole wall has to be pulled down to replace it. So, it’s important to keep the quality of workmanship high and for the roofers to proceed carefully.

“Luckily, this job went well and we didn’t damage any panels,” says Harkin. Even though installing insulated panels such as these requires fewer roofers to be on the job than with a standard roof, temporary safety nets were slung around under the eaves and edge protection was installed to ensure a safe working environment.

Harkin Roofing also installed internal Kingspan (KS1100 Cool Store) panels, 1100m wide and 11.8m long with a 125mm-thick core for walls and ceilings, in a vertical pattern. Internally, the warehouse space was divided by walls into areas, such as honey warming rooms, so insulated panels were chosen for this part of the project. Again, the weight of the panels made this a logistically challenging job, which called for a forklift and the cladboy to lift each panel into place.

Because the floor had been poured to achieve a high-quality flat finish, care was required during the internal installation. “We had to wait for the concrete to cure enough that we could go in without damaging it, and we used forklifts with white, non-marking wheels,” says Harkin. Installation was complicated, not only because the panels were so large, but also because the walls had to be able to move independently of the rest of the structure in the event of an earthquake.

The panels were fixed to the floor, but at roof level they were fixed into beams with oversized slotted holes, so if an earthquake struck, the walls and floor could move independently. Earthquake requirements also made the design and installation of the flashings complex. The flashings had to be designed to allow for up to 150mm of movement, and where the old and new buildings met, the flashings could not be tied together, but needed to be able to move separately if the building experienced an earthquake. “The new building looks really good, and
quite different with all its coloured panels; it really does achieve the appearance the owners and architect were aiming for, I believe,” says Harkin.