On shaky ground

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Vietnam lacks solid seismic standards for high-rise construction and few guarantees for apartment buyers

Residents stand outside an apartment building in Hanoi's Linh Dam residential area after an earthquake on March 24. The quake has raised questions about the quality of apartment towers in the country.

A 6.8 magnitude earthquake erupted along the border between Myanmar and Thailand on March 24 causing the upper floors of high-rise buildings to sway. The quake sent thousands of high-altitude Hanoians into panic, raising concerns about the stability of apartment towers throughout the country.

In a recent interview, Pham Si Liem, deputy chairman of Vietnam Association of Construction, told Thanh Nien Weekly that Vietnamese people have few assurances that their apartment will hold up in an earthquake.

Thanh Nien Weekly: How earthquake-ready are apartments in Vietnam?

Pham Si Liem: There are many different ways to measure quakes. Only a certain level of earthquake poses significant threat to most buildings. If a building quivers, that's not necessarily a cause for concern.

In Vietnam, we don't classify earthquakes according to Richter scale, we use a different metric. The highest earthquake level under our criteria (the MSK, or Medvedev-Sponheuer-Karnik earthquake intensity scale, once popular in some European countries) is a 12.

Hanoi is located in a zone prone to earthquakes up to level 7. For special buildings, such as important buildings or very tall ones, we should consider the city prone to eight-level earthquakes and base all our calculations on that assumption.

It is necessary to develop such a standard for important buildings as the Cultural Palace, the Ho Chi Minh Mausoleum, the National Assembly Building, the National Convention Center... But, it's not necessary for ordinary houses.

For high-rise buildings, it's necessary to develop similar standards, but I'm not sure if they do that or not.

For residential buildings, people make no calculations, they just reinforce their foundations. For example, when building houses, they create a steel frame and fill it in with concrete before building additional stories. If a tremor occurs, the structures can bear it. The tremor can cause some cracks, but no walls fall, no casualties happen.

But, how do you assess the quality of apartment blocks?

We use two metrics to evaluate apartment blocks. The first is the quality of the structure, which includes its foundations, girders or pillars.

The second is the quality of mortaring, paving or other external work.

Whether or not a block will collapse depends entirely on its structure. However, there have not yet been any complaints about structural integrity. All complaints center on the quality of mortaring, paving, and other cosmetic aspects.

What is the highest level of earthquakes that tenements can stand now?

As far as I know, our high-rise tenements can withstand earthquakes up to the level 8 (under the MSK earthquake intensity scale).

How can we strengthen state oversight on tenement quality?

We need rigorous inspection and surveillance. Investors should hire personnel to oversee any project, and ensure quality construction throughout a given project. There's no way to evaluate the quality of certain parts of a building after construction is complete.

Tenement buyers often rely on investors to ensure building quality, don't they?

There's no point in pouring through all the documents related to the building's construction after it is complete. There are cases in which people in charge of building oversight are irresponsible and allow the theft of vital construction materials, like steel.

In foreign countries, insurance firms supervise the construction of a given building, but that's not the case in Vietnam. Building owners in other countries must buy insurance, and insurers have to send quality surveillance experts to the construction site to oversee every critical phase of the construction.

What can home buyers do to ensure they're buying an apartment in a safe building?

They have no ways to do that.

Instead, all they have are inspection reports and other official documents. No tenement buyer is qualified enough to view and understand such documents. Therefore, they must rely on a guarantee from the contractor.

The builders should be required to deposit a certain amount of money (maybe 5 percent of the total value of the contract, for example) in a bank. Within two years, if problems arise, the money should be diverted to repairing the building.

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