NORMALLY on a Monday morning, Nick Rankin and Neil Jackson would be sipping espressos in Chiswick, west London, and discussing the week’s targets for the software development company of which they are directors. Last Monday they were shovelling rubble in one of the poorest townships in Cape Town.

Around them 40 employees who usually spend their days at computer screens designing search engines and websites for clients such as Direct Line Insurance, B&Q and Royal Bank of Scotland, were hard at work mixing cement, plastering and bricklaying. As for the owner and chief executive, she was digging a sewerage trench.

Tanya Goodin, a British entrepreneur, had taken her entire company to Africa for a week to build a block of classrooms and lavatories as well as a playground and basketball court for a deprived school in Guguletu.

The founder of Tamar and mother of two usually takes her staff on a more traditional annual away-day. Last year they went sailing in the Solent. But Goodin had resolved to do something more productive this year. However, she concedes, she got “a bit carried away” on the project that cost £100,000 - 10% of the firm’s projected profit.

“The company is 12 years old and doing very well and I thought it was time we gave something back to the communities we work in,” she explained. It was an idea that had been growing in the back of her mind since a near-fatal car crash in 2003. “I didn’t want to feel all I’d done with my life was creating wealth.”

She chose South Africa because Tamar had recently opened its first overseas office in Cape Town. For all its glitzy waterfront, packed with restaurants and tourists, there are sprawling townships of plyboard and corrugated-iron shacks less than 10 miles from the city centre.

A committee of younger company members was appointed to draw up a shortlist of projects. “As the mother of young children, I wanted something to help children,” Goodin said. “I also wanted it to involve physical labour - at Tamar we spend our time in the virtual world creating things that don’t physically exist so I wanted to create something tangible.”

They all agreed on Vuyani primary school, which had been built in the 1960s during the apartheid era and had far outgrown its few classrooms. What most impressed them was the charismatic headmaster, Mahlubi Ngqukuvana, who, they felt, had achieved a lot with very little and would look after whatever they did.

All he had asked for were new blackboards and repairs to the windows as children were getting asthmatic from the sand blowing in. But he also let slip that the school did not have enough space for all 774 pupils, aged 6 to 15, and was having to teach the youngest in a local church, carrying desks back and forth.

Goodin immediately rose to the challenge. “I thought if we brought the whole staff out for a week, that’s 280 man hours a day and we could do a lot more than just refurbishments.” She contacted Across the Divide, a Somerset-based organisation that helps facilitate projects for charities and companies. “More and more companies are wanting to do something to make a difference rather than traditional outdoor-pursuits team building,” said Ian McLaughlin, who headed their team. “But they are usually youth centres in Swindon or doing some gardening at an old people’s home. This is by far the most ambitious I’ve ever seen.”

Goodin admits she did not realise how much it would cost when she embarked on the project. Although the local building suppliers, Cash-build, donated some of the materials and labour, Tamar spent £80,000. A further £20,000 was raised by staff through wine-tasting, selling cakes, an eBay auction, and donations from friends and family.

One of the biggest fundraisers was Justin Stenner, head of production, who earned £1,000 in sponsorship for removing all his body hair. Yet he admits he was sceptical about the project. “I was worried about shutting down the office for a week and leaving our clients,” he said. “And I wasn’t sure that sending 30 people 6,000 miles across the world was the best use of the money.”

Others were worried about leaving behind family. One employee’s daughter was sitting GCSEs in that week; another was pregnant and had a two-and-a-half-year-old. Some even tried to pull out the day before.

Most had never been to Africa and were shocked by the shanty towns they passed on their way from the airport. Several admitted they were nervous. “I’m not very strong and I’ve never done manual work before,” said Nicky Rogers, who moved from London to head the Cape Town office.

At the start of the week, the chances of completing the classrooms looked grim. Cape Town’s wettest winter for years had delayed preparations and although the foundations had been laid, they were waterlogged.

“A lot of my energies over the last few weeks had gone on convincing staff,” said Goodin. “Then when we turned up on the first day and it was pouring with rain, freezing cold, thunder and lightning, water dripping through the plastic sheeting, I looked at their faces and thought, I’ve brought them 6,000 miles for this.”

They were also disappointed to find no children. A nationwide strike of public sector workers had closed all state schools since June 1.

But they quickly got stuck in, some teams assigned to small jobs such as replacing cracked window panes, while others were laying bricks, plastering and tiling. The faces of local builders who had been hired to supervise registered both amusement and alarm. “I’ve never seen white women doing building work,” said one.

Only a handful of the Tamar team had ever done DIY. Nick Rankin, the managing director, admitted he had recently struggled to construct an Ikea patio set.

Soon the web designers marking out the basketball court were having problems. The tilt of the surface meant however many times they measured, they could not seem to mark out a square. Over at the jungle gym, three other team members scratched their heads as they struggled to remember enough school trigonometry to work out the positions of the poles.

But the rain dried up and spirits rose. “Before I came out I couldn’t visualise what we were going to do,” said Rob Gaskarth, Tamar’s project coordinator. “But now, seeing conditions out here, the scale of the project and the effect it will have on people’s lives has really hit home.”

It is not only the school that will benefit. “I’ve never used a drill before in my life,” said Amira Burzic, the financial accountant, waving one alarmingly as she put up new blackboards. “But now I might try at home.”

Occasionally BlackBerries pinged with requests from the UK but Tamar’s clients had been briefed on the project, and only a few times did people have to rush to their laptops.

Ngqukuvana, the headmaster, looked stunned as the classrooms took shape. “It’s fantastic,” he kept saying. “They’re doing a big job for us.”

He admitted he had been taken aback by Goodin’s insistence on installing six toilets for the two new classrooms. Why became clear when he took me to the nearby Lotus settlement where most pupils come from.

Many live in former dormitories for migrant workers where 18 families share one bathroom. Most parents are unemployed and the children were coming to school so malnourished that they were fainting until Ngqukuvana secured the assistance of a feeding programme earlier this year. Now they get bread and soya-mince or jam before lessons.

The school provides no extracurric-ular activities as the children are expected to go straight home to help with chores or work, selling peanuts, chewing gum or phone cards at the railway station or on the highway.

By the last day of the week, the Tamar team were leaving their lodgings before dawn, desperate to complete their task. But the rain intervened once again and they had to wrap up, leaving walls to paint, floors to tile, doors to hang and basins to plumb in.

The building suppliers took pity on them and agreed to send in regional managers to finish the job as their own team-building exercise.

Such concerns were forgotten when the children arrived on Friday afternoon. Their eyes widened in wonder at the new classrooms and a mural painted with animals of the world. There was a whoop of pleasure as they rushed to clamber on the jungle gym with slide, rope ladder and swings, and to play on the new basketball court.

“We love it!” shouted Phumeza and Viwe, two cheeky nine-year-old twins in matching black woolly hats.

“All they had before to play on was this,” said the headmaster, pointing at a small tree.

“It’s amazing,” said Sarah Graveling, one of several workers wiping away tears. “It was worth all the hard work and aching backs.”

Goodin looked on proudly. “I could have spent the money on designer handbags, clothes or my own children but instead all of us will know for the rest of our lives that we’ve built classrooms in Africa,” she said. “I joked that next year we’re going to come back and build a hospital and none of my staff looked at all fazed.”

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