STEICO I-joists

Innovative load-bearing structures for maximum energy efficiency

The functional principle for STEICO I-joists is as simple as it is impressive: reduction. Where no material is needed, no material is wasted. The result: improved properties with low weight, low primary energy consumption and maximum energy efficiency.

How STEICO I-joists are manufactured

STEICO I-joists consist of two components: the so-called "flanges" on the top and bottom sides and the "web" in the middle that connects the two flanges. The flamge material is made of highly durable STEICO LVL laminated veneer lumber, one of the most resilient wood-based materials available. The web is made of STEICO Natural Fiber Boards, a wood-based material characterized by particularly high shear strength. 

In combination, this results in an innovative structural product that combines load-bearing capacity with low weight and maximum energy efficiency.

Applications of STEICO I-joists

STEICO I-joists can be used wherever conventional load bearing structures made of wood are used – in wall constructions as well as in roof and floor constructions. In addition, they are used in the façade insulation of solid wood walls and in the energy-efficient renovation of masonry.

Minimizing thermal bridges

The slim double-T shape of the I-joist combines maximum load-bearing capacity with low material usage. This significantly reduces thermal bridges. At the same time, the slim shape allows the amount of insulation to be increased. The use of I-joists can improve the U-value of a building component by up to 15%. Optimal for use in passive and plus-energy houses.

No shrinkage,
no twisting

Solid cross-sections of naturally grown wood are prone to twisting and shrinkage due to post-drying. Structural lumber can contain up to 18% moisture content. When solid wood is post-dried in the building, a 240 mm high beam can lose up to 5 mm in height. STEICO I-joists are completely different. Due to the manufacturing process and the special components, they are absolutely dimensionally stable. Shrinkage and twisting are virtually impossible with I-joists.

Perfect in combination with STEICO air injected insulation

Fast and economical

STEICO air-injected insulation is mechanically blown into compartments, where it compacts to form a compact insulation layer. The insulation is either applied during prefabrication of the building elements or later on the construction site. Air-injected insulation adapts exactly to the shape of the STEICO I-joists – full-surface, void-free and settlement-proof. Due to the mechanical installation, the work progress is particularly fast and the economic efficiency is especially high.


STEICOzell – air-injected insulation made from wood-fibers

STEICOzell consists of natural wood fibers without any harmful additives. The loose wood fibers interlock three-dimensionally during the blowing process, thus achieving maximum settlement resistance. 

STEICO I-joists – lighter than solid wood

Two product types for different applications


Innovative wall support for ultimate energy efficiency, e.g. for passive houses.



Innovative support system for ceiling and roof constructions.


STEICO LVL Laminated Veneer Lumber – structures for maximum load-bearing capacity

Maximum performance for forward-looking timber buildings – that is STEICO LVL laminated veneer lumber. Thanks to its unique structure of bonded softwood veneers, the result is a wood-based material with the highest strengths – for extreme load-bearing capacity where it counts.




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