The Philippines' giant band of overseas workers, already regarded as national heroes for toiling in foreign lands, are coming to the rescue again as they dig deep to send more cash back to their typhoon-hit homeland.

With relief workers overwhelmed by the magnitude of this month's disaster and unable to provide adequate support to the millions of survivors living in flattened towns, Filipinos abroad are proving a crucial, direct lifeline.

In the ruined city of Tacloban, farmer Teudolfo Barmisa queued up at a money transfer outlet on Tuesday and withdrew the equivalent of $600 sent by his daughter who works as a maid in Hong Kong.

"The money will go to buying food first, then other supplies to help us rebuild our home, like plywood and cement," Barmisa told AFP.

Barmisa was among hundreds of people withdrawing cash from financial outlets in Tacloban, many of which had just re-opened more than a fortnight after Super Typhoon killed at least 5,240 people and destroyed or damaged one million homes.

Barmisa's daughter and the other 10 million Filipinos working abroad are commonly referred to at home as "mga bagong bayani", or "new heroes", because of their sacrifices in leaving their families to work abroad.

The number overseas is roughly 10 percent of the population -- with many of them working as domestic helpers, labourers, sailors or in other low-paid professions -- and they often send much of their savings back home to relatives.

They are forced overseas because, despite impressive economic growth rates in recent years, the Philippines remains in large part a desperately poor country, and their remittances has long been an important plank for the nation's economy.

The overseas foreign workforce last year sent home $21.39 billion via bank transfers and other official channels, equivalent to nearly 10 percent of the Philippines' gross domestic product. Even more money arrives unofficially.

Overseas heroes give more

And when a major disaster strikes in the Philippines, the amount of cash coming home spikes.

Remittances jumped an average of 13-14 percent over the nine months that followed the country's previous 10 deadliest typhoons, Patrick Ella, a Manila-based economist at the Philippines' Security Bank, told AFP.

A 14-percent increase over three quarters would equate to about $2.3 billion, based on last year's remittances.

"But Typhoon Haiyan was definitely an outlier, so the gains will probably be more than usual because of the extent of the damage and the well-publicised problems in the distribution of relief supplies," he said.

Haiyan was one of the strongest typhoons ever recorded and generated freak storm surges that swallowed up entire towns.

The confirmed number of fatalities has made Haiyan one of the deadliest storms ever in the Philippines, and it could turn out to be the most destructive on record if, as expected, the death toll continues to rise.

Exacerbating the catastrophe is that the worst-hit areas, the eastern islands of Leyte and Samar, are among the poorest in the Philippines, with most of the four million people there enduring near subsistence farming or fishing lifestyles.

Barmisa, the farmer, said his family had managed to buy a vehicle, a small home and little shop on the outskirts of Tacloban using the money sent home by his daughter over the six years she had worked in Hong Kong.

All of that was destroyed in the storm surges.

"Hopefully, when she returns home we will have a house again," he said, as he left the money transfer outlet with his daughter's money.

Overseas workers return home

Some overseas foreign workers have also left their jobs overseas to return home directly with money and emotional support.

Among them is Lourdes Distrajo, a 27-year-old single mother of two, who lost a son and 12 members of her extended family in the disaster.

She had only recently started working in Kuwait as a maid, and had hoped her $700-a-month salary would pay for her children's schooling, renovations to her wooden home and sister's medical bills.

Instead she had to quickly return to help with the family tragedy.

"My employer was kind enough to allow me to leave, packing supplies and giving me extra cash and a return ticket," she said.

Distrajo said all the money she had brought home would be left with the family, barely enough to be able to buy some wood to help rebuild their home and stock up on some supplies.

Distrajo has yet to start dealing properly with the grief of losing her four-year-old son.

"I didn't even see his body. He was buried in a mass grave along with many others... I keep asking myself, was it worth it to work abroad? Maybe I could have saved my son," she said.

But she has no choice to soon return to Kuwait, so that she can once again start sending money back home.