Koto 8 Energy Efficient IBS Building System
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Installing K-Blocks
Structural Engineering Description

Koto building system is made up of a series of vertical reinforced concrete cores connected top and bottom to horizontal reinforced beams. Depending on the application the system can alternatively act as “LOAD-BEARING CONSTRUCTION”, “SHEAR WALL CONSTRUCTION” or “COLUMN AND BEAM CONSTRUCTION” simply by varying the spacing of the vertical reinforced cores. For houses where there are minimal vertical or horizontal forces, the system is designed as if it is Column and Beam.

For high rise construction the system is designed as a combination of load-bearing walls (for building loads) and shear wall construction (for wind and earthquake loads).

The reinforced cores are designed as:-

  1. Compression members for vertical load.
  2. Simply supported beams for horizontal face loads on the wall.
  3. In combination with the horizontal beams, designed in a similar way to a Vierendeel truss for racking forces.
Suitable for
  • Residential and Commercial
  • Large volume mass housing
  • Koto Eliminating Poverty Packaged Programs
  • Up-market
  • Link homes
  • Apartments
  • Resorts
  • Schools
  • Eco villages
  • Workers quarters
  • Walk-ups and High rise
  • Floating residential or commercial

A highly respected architects description:

The Koto System is so revolutionary that even expert people may not fully understand the system until they physically see it.

Once seen however, it quickly becomes apparent that the main benefit of the light weight block is that it does not need to support its own dead load weight because that is counter intuitive.

As concrete spanning members and columns are normally seen, it is hard to comprehend that Koto is capable of doing the same spans BUT with very little structural depth.

As such this revolutionary permanent concrete form offers absolute versatility.

Download description in Chinese and Malay: Download file


Dead Load Weight

Conventional concrete column and beam construction with plastered brick infill: 3,400 Kg per m3.
Koto building system for low wind-speeds: 340 Kg per m3 and for high wind-speeds: 690 Kg per m3.


Thermal Resistance

Thermal U-value of a 200 series system is .82 equating to excellent thermal resistance. Therefore only lower kw air-conditioning units are required, reducing loads on the national grid in hot climatic conditions.

In minus 30 degrees temperatures such as the Koto Korea plant for example, K-Blocks are manufactured anywhere from 250mm to 300mm thick ( .45 U-value) to protect end users against severe winter temperatures, herein requiring only small heating apparatus for family homes.

Design Flexibility

The flexible choice of products allow for designing in earthquake zone 3 applications and cyclonic wind-speeds of 60-70 metres per second. By simply inserting the simple Koto lintel or core hole configuration easy use of vertical beams, and incorporating the K-Deck flooring systems as part of the bond-beam, where multiple columns connect to the foundation thickened slab through to the top ring-beam.

K-Pod Raft Slabs

Contractors and engineers prefer K-Pod raft slab foundations due to their ease and speed of installation, guaranteed network of beams connecting to a thickened perimeter edge beam, reinforcing steel in the right place, less concrete required, termite resistance without chemicals, and overall excellent performance.

Designing With Wall Modules

The module dimensions for Koto 8 walling offer architects easy increments to work with that suit most applications without contributing to waste. 150mm and 200mm wide K-Blocks are in modules of 1.2m and 1.8m long respectively and manufactured in any height dimension increments of 300mm.

  • The common and popular standard Horizontal K-Blocks are 900mm high and 1.2m high respectively.
  • The common and popular standard Vertical K-Block is 1.2m wide, by full wall height.
  • Bond-Beam blocks for the top course are ex-factory with a pre-cut u-beam provision for ease of use. Just place specified steel and concrete.
  • K-Blocks can be joined together to provide lineal wall sections of 1.2, 1.8, 2.4, 3.0, 3.6 and so on.

All Koto 8 K-Blocks have male and female connections at either end of the block, including top and bottom male/female connections. This means that contactors cannot abuse or misuse the modules as they all connect and bond together by simplicity and without need for stabilising braces or ties.

The most important features of the K-Blocks are accuracy, flexible engineering and thermal stability, all of which disallow outside temperatures to penetrate or store energy in the walls and roof, and where the koto processing line automatically installs the high impact resistant coating from a controlled environment.


Koto K-Blocks slide over the starter bars and are permanently bonded to the substrate/slab with an environment friendly 2 pack water-based, mineral Koto Bonding Paste. Additional courses of block/panels use the same material and bonding technique. The same Koto bonding paste can also be used to bond starter bars into concrete floor slabs, bonding metal stiffeners into floor decks, embedding timber into a substrate, pvc pipes etc. as it has extraordinary permanent bonding power.

Window and Door Openings

As windows are commonly set at 900mm high from the floor slab, the Koto 8 900mm high K-Block/panels are ideal for walling and quick window installation.

In South-East Asia, Koto recommends Econo cold rolled window and door frames due to their super-fast installation and more importantly, the K-Block panels fit snuggly into the frames leaving a straight rigid architrave around all surfaces. These cold rolled designer frames are also commonly used in cyclonic regions because of their design. Standard louvers and sliders are all available with right and left door options.

Koto Floor Decks and Roofing

Architects and engineers are afforded the manuals for their reference and checking for compliance to code.

Test Results

Testing and reports are conducted by the government testing authority SIRIM International BHD in accordance to British Standards. Sirim has one of the most modern and superior testing facilities found anywhere in the world.

In other countries it can be negotiated usually to have a registered authority provide an opinion on the Sirim reports as all testing methodologies, procedures and principles are known. British Standards are considered by any authority as conservative.

Koto products and designs are design registered. All documents and photos are copyright. © kotocorp.com