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The KES System’s high-quality hot-dip galvanizing of its metal joint-plates significantly increases durability and resistance against rust.

The steel jointing-plates of the KES System are all galvanized, giving significant resistance to rust. The galvanizing coat has a thickness of more than 500 g/m2, which is a higher specification than highest grade of the JIS (Japan Industrial Standards), and higher than the galvanized coating of infrastructural electric wiring, which has a thickness of 350 g/m2. In buildings in coastal environments, steel with conventional cathodic coating will begin to rust after 50 years, while steel with a galvanizing coat of 500 g/m2 of electrodeposited zinc are estimated to last for more than 173 years.

Characteristic of Hot-Dip Galvanizing

The Galvanizing coat consists of electrophoretic layers that are tightly bonded together, forming a cohesive coating that protects the core steel without exfoliation or cracking in all normal conditions.

The top surface of the zinc coating binds with oxygen electrochemically, becoming zinc carbonate. This process, which protects the core steel, is called sacrificial corrosion.

Conventional paint only shields the steel from oxygen and water. When the coat of paint is scratched or broken, the steel begins to corrode.

As the pioneer of metal joint systems for timber structures,
The Shelter Company has a obtained a wealth of accumulated knowledge

The Shelter Company is the originator of advanced timber frame jointing systems in Japan. Since our prototype structure was developed in 1974, the system has been patented across the world, and we have accumulated a wealth of experience and expertise.

S Mark granted; another assurance of quality.

After the Hanshin Earthquake, it was recognized that the improvement of timber frame structures was an urgent issue for the Japanese building regulations. It is now required that the strength of every structural element be documented. In one of the first determinations of this new compulsory certification, the Japanese Government granted the KES jointing-system an ‘S-Mark’ (Safe mark). In addition, all houses in Japan built using the KES System are covered by a building indemnity insurance, which gives additional peace of mind to our clients.

High quality fastenings are essential to achieve strong timber frames.

The KES System uses high quality nails and steel-pins for the connections of the timber frames. Nails are used for connecting walls and floors, while steel-pins are used for connecting beams and columns. We very carefully select high-grade nails and steel-pins, and properly supervise their placement.

Comparison of KES System joints and conventional joints

The Strength of a building depends on the strength of its structural joints. The chart below compares the KES Jointing system with a conventional timber-framed structure. The KES patented connectors resist earthquakes and achieve very superior durability.

KES System