Burj Zanzibar - TOWER of the future

Why the size and structure of Burj Zanzibar –set to be the world tallest timber tower in the world – could be the secret to the island’s sustainable success.

The Fumba Peninsula is a 14km by 3km promontory south of Zanzibar’s capital flanked on both sides by pristine coastline. Sebastian Dietzold compares it in size and shape to the island of Manhattan in New York.

The urbanisation of Fumba over the past decade – overseen by the German-led engineering firm CPS Dietzold founded with his wife, Katrin – has advanced the similarity. Launched in 2015, Fumba Town is Zanzibar’s first eco city with already over a thousand state-of-the-art apartments and villas housing a cosmopolitan community supported by on-site schools, universities, shops, health centres and even an organic food delivery service.

If Fumba Town is Zanzibar’s Manhattan, then the Burj Tower looks set to be its Empire State Building. At 96 metres in height, the 27-storey timber tower will be an iconic addition to the Fumba skyline. Dietzold describes the development – which will include a Canopy by Hilton luxury hotel on the first six floors, topped by 187 sea-view apartments and topnotch amenities throughout – as Fumba Town’s “flagship building”. Currently all that exists are some mouth-watering artist’s impres- sions of the tower – including its ultra-luxury penthouse suites with roof gardens and spectacular public spaces such as the roof bar, pool and gym – with the ground-breaking ceremony scheduled to take place early next year and completion anticipated in 2028.

Record-breaker

Already the building’s headlining height has attracted global media attention. If Burj Zanzibar was built today it would be the tallest timber tower in the world.

The scale of the Burj and the natural materials used to build it are integral to the Dietzolds’ vision for sustainable urban development in Zanzibar and beyond.

“The tower will be our landmark,” Dietzold says. Not because it’s a glamorous highlight but because it will promote responsible, sustainable buildings and trigger a whole new industry in Tanzania, from agroforestry to the production of engineered wood products.”

“The Burj Zanzibar tower is part of our mission to meet the massive housing demands in Africa in a responsible way. We want to support a technology that protects our planet.”

Tanzania has one of the fastest rates of population growth in the world with the number of citizens projected to reach 100 million by 2035. That’s more than a 50 per cent rise on the current figure. When working with mother nature, Dietzold believes high rise buildings can be the answer.

“60,000-plus new homes are needed in Zanzibar Town over the next 15 years,” he says. “Space is limited on Zanzibar. We have to go up.”

The Zanzibar government is aware of the housing shortage and gave permission to CPS to create an inclusive urban development.

Across its 149-acre site that fringes 1.5km of coastline, Fumba Town is already more than a third of the way towards building 5,000 units with the emphasis of the last stage of development – known as Phase 3 – on more high-rise properties with Burj Zanzibar at the pinnacle.

“Fumba Town has been designed for two to three million people in the long run,” Dietzold says. “Phase 1 began with two-storey buildings, now there are three-storey and four-storey buildings. Phase 3 will be predominantly high-rise and will give the development more of a city character.”

Wonder of wood

As well as the raised height of its new buildings, Fumba Town is featuring increased use of cross-laminated timber (CLT). Dietzold describes it as “the concrete of the future” and is so sold on its benefits that when we connect on Google Meet for this interview, he appears on my screen from the office of his timber-built villa in Fumba Town where he lives with his family. “We feel like this is home now,” he says.

CLT is an engineered product consisting of layers of wood boards stacked in alternating directions and glued together. The result is a solid, durable panel that has the load-bearing qualities of concrete, without its heavy carbon footprint. Conventional concrete construction is responsible for around a quarter of global CO² emissions while CLT absorbs carbon during the building’s lifetime. Measures that can stem the march of climate change on the fragile ecosystem of Zanzibar Island are crucial. Building a sustainable future here is a goal shared by CPS and the Zanzibar government. Currently, the wood is sourced from Austrian spruce forests and fabricated as CLT panels in the same country by Binderholz, a global leader in timber construction.

The panels are then shipped to Zanzibar where they are kitted together Lego-like by local construction company Volks. house. Dietzold is proud that the 160-strong Volks.house team is predominantly made up of neighbouring villagers trained to assemble the timber-based homes in super quick time.

“We have moved from construction to production,” he says. “Our mass-made timber homes are an important development if we are to keep up with demand.”

Talented team

The team’s work is so finely tuned now that its latest project, the three-storey timber homes that make up Fumba Town’s new Vizazi collection, was completed in just seven weeks earlier this year.

“We have around eight years’ experience with timber homes,” says Dietzold. “Our team is becoming internationally recognised for its expertise. We have had recent requests from German buyers wanting to make use of our workforce.”

These smaller projects are priming the team for the big one: Burj Zanzibar. The design by OMT architects features timber columns and beams as well as cross laminated timber slabs to form the tower’s honeycomb-like outer structure. This will be built around a steel-reinforced concrete tube at its centre.

The inclusion of conventional materials at the building’s core is to ensure all required fire and life safety standards are met. While there are all-timber towers in Norway – including the 85.4-metre-high current record holder in Mjøstårnet – and Switzerland, they are not permitted in Zanzibar.

While he accepts the ruling, Dietzold points out that CLT is renowned for its inherent fire resistance.

“It’s funny that people think timber is more combustible, but it is the opposite. Engineered timber structures are safer than concrete – we know how they react under fire. We have been working with [fire safety service] Ingnis running thousands of fire tests. If you heat timber walls to 1,200º they just crust and that crust is a heat insulator – the temperature doesn’t rise more than 10 degrees inside.”

Dietzold adds that CLT remains structurally stable when subjected to high temperatures and – fond as he is of a Big Apple-analogy – he references one of the most tragic moments in New York’s modern history to power his point: “If the World Trade Centre was a timber construct it would not have crashed to the ground.”

The chance to own a part of such an iconic building and to enjoy elevated living has meant apartments in Burj Zanzibar are selling fast. Dietzold says over half of them have already been snapped up. As with the rest of the Fumba Town development, buyers and investors have proven to be a cosmopolitan crowd. “We have had buyers from around 60 countries, including the US and UK” Dietzold says. “Many are Africans. Zanzibar is a safe haven on the continent and now you can get residency for US$ 100,000.”

Creative culture

The majority, though, are Tanzanians with Dietzold saying it was always in the CPS plans to target the country’s rising middle class with their pricing. Apartments in Fumba Town start at just under US$ 38,000 while you can get a studio in Burj Zanzibar from US$ 108,442.

The influx of these young professionals is helping to build a vibrant culture in Fumba Town. The fine homes are attracting fine minds. Last year the Indian Institute of Technology opened its first international branch in Fumba while the eco city is also home to the African School of Economics, which has 5,000 students.

“There is a culture of innovation growing. Fumba is transforming. We are trying to make a change here,” says Dietzold.

The Burj is a symbol of that change, but I ask Dietzold whether any of the early Fumba Town residents are concerned that their homes will soon be in the shadow of a gigantic neighbour.

“There has been some criticism, but most people are excited,” he replies. “Everybody who bought into Fumba knew this was growing community and it would evolve over time. The Burj is already attracting investment and all Fumba homes are appreciating in value as a result.”

With residents onboard with the changes charted for Fumba Town, the city moves forward with the sustainable future of Zanzibar at its heart. Construction of the Burj will require a huge increase in timber, which CPS is hopeful it can begin to source from Tanzanian forests. “It will simulate a lot of investment in the Tanzanian timber industry,” says Dietzold. “Tanzania has huge pine forests in the south. Pine is fast-growing so you can sustain the lumber stock for a long time and create a circular supply chain.”

The CPS website singles out a forest development in central Tanzania near Iringa. Its size? Twice that of New York.