A decade after being orphaned by the Asian tsunami, British brothers Rob and Paul Forkan are successful entrepreneurs who are giving back to the Sri Lankans who helped them by building an orphanage.

The brothers, their two younger siblings as well as their parents, Kevin and Sandra, were relaxing in their hotel complex on December 26, 2004, when the giant wave crashed through their bungalows.

Rob and Paul managed to climb on the roof and clung on as the water rushed by.

When the wave subsided, Rob saw his brother Mattie perched on a tree, his face covered in blood.

A little later, the brothers located their badly injured sister Rosie, placed in a tree by their parents moments before they disappeared.

Aided by a young Sri Lankan who had just lost his mother, Rob tried to track down his parents, visiting several hospitals and stumbling across scenes of devastation that still haunt him today.

Empty-handed, the siblings set off on their own, travelling on foot and by van to the capital Colombo, 150 kilometres from their hotel in Weligama.

Ten years later Rob, 27, and Paul, 25, recounted their incredible story and their philanthropic work, wearing their trademark flip-flops and Bermuda shorts in their beachwear company's London office.

"When we were in Sri Lanka and we got affected by the tsunami ourselves, and we lost our parents, the children of Sri Lanka helped us get home. So this is kind of returning the favour," Rob said.

The two have published a book this year about their experiences entitled Tsunami Kids and in the coming weeks, they will inaugurate what they hope will be the first of several orphanages on the island.

The institution, which will accommodate 400 children, will be financed with part of the profits of their flip-flop business through the charity they have set up - "Orphans for Orphans".

The brothers have travelled to Sri Lanka this week ahead of the orphanage opening on what is only their second visit to the island since the tragedy on Boxing Day 2004.

(TV 3 News)