Mario Kleff designed the longest steel box girder used in residential construction in Thailand

It was early March 2022 in Pattaya when the delivery of 50 tons worth of custom fabricated steel, in the form of box girders and cellular beams arrived at the Majestic Residence construction site, Khao Phra Tamnak.

The architect Mario Kleff and his construction company Wandeegroup Asia Co Ltd continue to set new standards in residential construction in Pattaya and across Thailand. It was just last year when Mario initially installed the longest cellular beam with a length of 48 metres between two columns to support heavily post-tensioned concrete floors.

At the beginning of 2022, Mario’s team had installed an assembly of box girders and cellular beams to form the foundation for the penthouse of the now 2,500 m² villa.

With a joint effort, between Wandegroup Asia Co Ltd and B.S.Y. Group PLC, large box girders were installed to achieve a cantilever reaching over 19 metres to each wing side starting from a centre column. The enormous steel girders were designed by Mario himself and fabricated in Samut Prakan by B.S.Y Group PLC.

Since as far back as 2005, the eclectic architect, Mario Kleff, of Pattaya City, has been innovating construction and engineering solutions within the residential sector. In over a decade, numerous villas and condominium blocks were designed and built by the Wandeegroup, most of which have been approved by a higher engineering level to grant the planning permission.

In 2010, Mario Kleff had his first encounter with Dr Songkiat Matupayont, an expert engineer from Bangkok to examine and support the design of Park Royal 2 on Khao Phra Tamnak. It was the first multistory residential building in Thailand with a steel frame structure built with long span cellular beams and post-tensioned concrete floors.

Two years later in 2012, the same team created the first permitted high-rise precast concrete structure with only two columns and with a span of 25 meters, named The Touch. Dr Songkiat was excited to learn of Mario’s plans for the new project at the Majestic Residence. Dr Songkiat is quoted as saying “…48-meter-long cellular beams and large box girders to build a villa. Wow!”. Both began to collaborate on the design sometime later and the villa entered the construction phase in summer 2021.

Although the exterior of the villa is rather bland in appearance, the construction procedures and the building performance are immense with over 220 tons of high-grade steel and more than 1,200 m3 of ultra-high-strength concrete mix. Through the use of large cellular girders and steel rods (up to 32mm in diameter), Mario and his team were able to cast the concrete supporting columns. To ensure the safety and best performance of the building, all floor plates were designed by the team consisting of Mario Kleff, Dr Songkiat Matupayont, Prapat Boonlualoah and Sadudee Boonlualoah from Span Systems International LTD.

Built on a solid foundation set on over 100 bored piles is a huge 550m² basement. A large pool over 20 metres long and a two-storey-tall waterfall and a whirlpool structure make up part of the 900m² ground floor space. On the second floor, the villa offers over 700m² of private space in the form of a large master bedroom and two additional guest rooms. The ground floor and the second floor includes large (3×42 metres) crystal-clear antireflective glass panes. Due to the use of long-span cellular beams, Mario was able to create uninterrupted views over the pool deck. The top floor consists of a 350m² penthouse with sea and city views across Pattaya.

This villa was confirmed by the local building authorities, engineers, and suppliers as the first residential building with the longest span between columns, with the largest steel box girders installed, and built with the highest strength concrete mixture available from CPAC. The villa has a state-of-the-art water, electricity and air conditioning system designed by Erik Gubbels. 1,000,000 BTU will ensure cool spaces throughout the property.