Yet on a recent morning, Mr. Othaim watched contentedly as a group of men renovated the place using exactly the same ancient methods and materials. Workers mixed the moist chocolate-brown masonry known as teen while a master builder supervised, a dagger hanging from his belt. There was no scaffolding, no helmets, no whine of machines: only the scraping of trowels and masonry, interrupted at last by the call to prayer in the high desert air.

“I don’t care how long it takes,” said Mr. Othaim, a government worker. “The most important thing is that it be done in a traditional way.”

The capital’s Old City is one of the world’s architectural gems, a thicket of unearthly medieval towers etched with white filigree and crowned with stained-glass windows. But more unusual than their mere survival is the fact that the traditional building arts continue to thrive here. Elsewhere in the Middle East, many older houses are being ripped down to make way for bland steel-and-glass high-rise buildings. The hyper-modern skyline of Dubai, United Arab Emirates, with its mismatched skyscrapers looking as if they were hurled down at the Persian Gulf from outer space, is being emulated in Beirut and other cities.

Yemen is different. For all its many woes — wars, a water crisis and the rise of Al Qaeda — the country’s adherence to ancient traditions often makes it feel like a refuge. Even outside the Old City, the bands and crescents of medieval Yemeni architecture can be seen on many newer buildings and homes, along with the translucent alabaster windows known as gammariyas.

The traditions stayed alive largely because of Yemen’s deep poverty and long isolation. Until 1962, north Yemen had been ruled for almost a millennium by xenophobic imams who tried to shut out all foreign influence. The country largely missed the urban renewal phase of Arab history, in which kings and presidents cleared out ancient neighborhoods and markets in an effort to bring their nations into the modern age. By the early 1980s, when Yemen was still emerging from its medieval slumber, preservation was already in vogue.

There was much to preserve. This country has been famous for its unique architecture ever since Sabaean rulers built the skyscraper palace of Ghumdan 1,800 years ago, celebrated by one medieval poet thus:

It rises, climbing into the midst of the sky

twenty floors of no mean height

wound with a turban of white cloud

and girdled in alabaster.

Architects rediscovering the Old City soon found there was more than beauty at stake. The traditional houses were also more durable and effective than concrete-based modern houses, and better suited to the climate.

“The traditional houses have many environmental advantages,” said Abdulla Zaid Ayssa, the director of the government office that oversees all building and renovation in the Old City.

The traditional plaster, joss, does not erode stones over time the way cement does, Mr. Ayssa said, and is more durable. Qadad, a stone-based insulation material used in roofs and bathrooms, is much stronger than modern equivalents. The old stones and insulation techniques are calibrated to the sharp temperature shifts of night and day in Sana’s desert climate, so that the sun’s warmth fully penetrates a house’s walls only at day’s end, and is then retained through the night and no longer, Mr. Ayssa said. They are also much more soundproof and private than concrete.

“They experimented for hundreds of years to find these techniques,” Mr. Ayssa said. “By comparison, nowadays we are building houses with a very stupid concept.”

Yemen did not preserve everything. Only a few decades ago, there were 10 or 12 massive gates to the Old City; now only one remains. Some zealous republicans associated the older architecture with the reign of the imams, and thought it should be destroyed.

Still, Yemen kept far more than many other Arab countries did and, in 1986, Unesco, the United Nations culture agency, recognized the Old City as a World Heritage site, helping to secure money for its maintenance. Mr. Ayssa’s office helps subsidize the continued use of traditional materials and methods, which often cost more than modern ones.

To prevent the Old City from becoming a mere museum, the government built a modern sewerage system in the 1980s. It cobbled the ancient earthen streets, which had led one Italian writer to call the city a “Venice of dust.”

Now it is almost too crowded, and the authorities find themselves struggling to suit the city’s architecture to new ways of living. The ground floors that were once used for camels and goats have been largely refitted as stores. Those shops are undermining the central market, the social and cultural heart of the Old City. Still, local residents seem wedded to the traditional architecture and the rituals that go with it.

“Everything is changing in the city, but still, generation after generation, it continues,” said Mahmoud Qais al-Arousi, a 65-year-old builder, as he stood watching his workers mix masonry outside Mr. Othaim’s home. The building, he pointed out, still has scrape marks on its stone corners from where horse-drawn carriages would pass by. It was once inhabited by Nasser Salahuddin, a local notable who died 720 years ago.

With Mr. Arousi were his three sons, all of them apprentices to him. The building trade goes back hundreds of years in his family, he said, and his sons are planning to continue it.

“I learned by following every step my father made — the stones, the hizams,” Mr. Arousi said, referring to the distinctive horizontal belts running around Yemeni houses. “My sons are doing the same.”

Robert F. Worth, The New York Times, 16.11.09

http://www.nytimes.com/2009/11/16/world/middleeast/16yemen.html?_r=1&ref=middleeast