The material of the structural frame is Kerto® as well as the Finnjoist I-beams produced by the company Metsä from Finland.

The beams are similar in shape and function to the known I-profiles made of steel, only made of wood. These light-weight beams have been staticly optimised that they can bear high loads, while requiring minimal use of material.



Kerto® LVL – laminated veneer lumber

Metsä Wood's Kerto® LVL is a laminated veneer lumber product used in all types of construction projects, from new buildings to renovation and repair. Kerto® LVL is incredibly strong and dimensionally stable. Kerto® LVL delivers its high strength from the homogeneous bonded structure.


Metsä Wood Finnjoist® (FJI)


Metsä Wood Finnjoists® (FJI) are manufactured from high quality oriented strand board (OSB3) web, and flanges made from their own Kerto® LVL (laminated veneer lumber).  The engineered timber I-beam joists deliver strength and rigidity, virtually eradicating floor movement and its associated problems, resulting in greater floor performance.


Thanks to excellent properties of Kerto Finnjoist is incredibly strong and dimensionally stable, and it does not distort or shrink. It derives its high strength from the homogeneous bonded structure and is an excellent flange material. Finnjoist I-beam is lightweight yet incredibly strong, resulting in a quick and reliable installation.

The advantages of ESB

  • Flexural strength and modulus of elasticity in both directions
  • Higher transverse tensile strength than OSB (approx. 40% higher)
  • Lower swelling than OSB
  • Very light surface and excellent optics
  • Fresh wood without odor emission
  • Ground surface

ESB is included as a one-sided ceiling formwork for types A and C in the support package. In the case of type A (gable-roof), ESB is also used for forming the jamb wall. (Also included in the structure package.)