ISRAELI BUILDING inspectors face a 'looming crisis' after it became clear this week that use of the controversial Pal-Kal floor construction system was five times as common as previously thought.
The system was at the heart of the disastrous collapse on 24 May in which 24 wedding guests were killed when the top floor of Jerusalem's Versailles Hall caved in as they danced.
But despite being effectively outlawed by the Israeli Standards Institution in 1996 for failing to meet design code specifications for shear resistance, contractors have continued to use the low-tech and cheap floor construction method across Israel.
Muller Schnabel Zacher partner Asher Muller, a member of the Institution committee that looked into the system, confirmed that it was still being used: 'I had a call today from a couple who had bought an apartment in a 15 storey block under construction. They had spotted the void formers that are typical of Pal-Kal being installed.'
A crisis is looming, he added, as there is no known cost effective technique for strengthening Pal-Kal floors and bringing them up to current standards.
'The only thing you can do is reduce effective spans by inserting a transverse steel beam at midspan, ' he said. 'This is expensive, and may not be physically possible in some cases.'
The Israeli Supreme Court is to set up a five man commission of inquiry into the safety of all public buildings after the Versailles Hall tragedy. The commission should find out why the system was still in use despite warnings and a series of failures.
The Pal-Kal system has no conventional shear reinforcement. But use of the system continued largely because it needed no skilled labour such as steelfixers. Some 2.5M. m 2of PalKal floors have already been identified, said Muller, and more are being discovered every day.
He said that Israeli structural engineers were being beseiged by anxious building owners seeking information on the type of floors in their properties.
So far no use of the Pal-Kal system outside Israel has been discovered. It is known that its inventor tried to market the system in the US, but without success. He is still in custody.