Skip to main content


Triple security for timber construction

What are three-layer slabs?

KONZEPT 3 ply panels hold a National Technical Approval from the supervisory authorities of the German Institute of Structural Engineering in Berlin (approval no. Z-9.1-209). They may be used wherever the deployment of grade 20, 100 and 100G derived timber products is admissible (with wood preservation treatment applied by the user). This opens up enormous creative scope for structural designers and planners.


Three-layer slabs (3S slabs) are glued from three layers of solid wood, at which the wood fibres of the adjacent layers running at an angle of 90° to each other.

The slabs are available in the types of wood spruce and fir, in various formats, thicknesses and qualities.

Modified MUF resins are generally used for gluing.

By selecting the thickness of the individual layers, the elastomechanical properties can vary greatly, even for slabs of the same overall thickness.



    • high-quality – selected woods, careful production, first-class gluing
    • flexible – numerous formats, many strengths, all qualities
    • economical – large-sized, high degree of prefabrication
    • ecological – wood from the region, PEFC certified
    • safe – permanent self-monitoring of production, CE marking, building authority approval


    fields of application

    interior fittings e.g. furniture, wall cladding
    timber construction for constructive and load-bearing use


    basic information performance programme

    • middle position: spruce
    • ceiling slats: juncture glued
    • bonding quality: SWP 2
    • use class: 1 and 2
    • wood moisture: 8 – 10%
    • edge processing: groove and tongue, groove and groove
    • surface coating: Aqua clear lacquer, Aqua intensive white, special colours available on request
    • packaging: the packages are packed with a protective film
    • minimum order quantities: acceptance in packages, individual slabs possible at extra charge
    • stock + processing instructions: slabs or packages must be protected from weather influences, more information can be found in the download area. Downloadbereich

    Concept 3S

    three-layer slabs with building authority approval

    SchwörerHolz also offers the three-layer slabs with building authority approval (Z-9.1-209)

    Schwörer CONCEPT three-layer slabs may be used for all executions where the use of solid wood slabs and construction veneer plywood is permissible, in particular as load-bearing and stiffening planking for the production of wood panels (wall, ceiling and roof panels) for wood houses in panel building technique.

    The components may only be used for predominantly static loads in accordance with DIN EN 1991-1.

    The use of these slabs for the reinforcement of breakthroughs and notches is not permissible.


    3S-installation slab

    for the fast manufacture

    3S-installation slabs for the interior fittings

    If you want to work efficiently in interior fittings and you are looking for a particularly attractive derived timber product, you will find it here. The edge processing with tongue and groove (or groove - groove) and the excellent technical properties allow an universal use.

    The installation of the slabs can be laid "floating" as well as nailed or screwed to substructures. It should be noted that a circumferential expansion joint of approx. 2 cm must be provided on the walls so that the slabs can work in the event of moisture changes.

    3S-installation slabs for walls and ceilings are also available with chamfered edges.

    A surface coating is possible on request.

    application and area of application 3S-slabs

    You differentiate between 3S-slabs with and without building authority approval.

    slabs without building authority approval
    ... are intended for decorative, non-load-bearing area of application. The gluing quality is comparable with SWP 2, analogous to DIN EN 13354.

    slabs with building authority approval (CONCEPT 3S)
    ... may be used in dry and damp areas according to DIN EN 13986.


    storage and processing instructions
    The slabs must be stored lying flat in closed and dry rooms and must be carefully covered. Improper storage or use in extreme climate areas may result in damage for which no warranty is given.

    area of application

    Due to the gluing with extremely low-formaldehyde MUF resins, the upper limit of formaldehyde emissions from derived timber products prescribed by the Federal Health Office is fallen below.

    Furthermore, no toxic substances such as isocyanate, phenol and solvents (see Ordinance on Hazardous Substances of 26. 08. 86) are contained in the gluing.

    Therefore, these slabs can be used according to current knowledge as practically harmless in all rooms (also in kindergartens etc. ).


    Despite the high-quality gluing and the approval by the German Institute for Building Technique*, the physical properties of the natural product wood must be observed:

    • Wood "works", this property must be taken into account by suitable measures (shrinkage and expansion joints, fastening).
    • The slabs must always be protected against climatic influences and moisture during the entire construction period.
    • The moisture content of the slabs must be checked before processing and, if necessary, must be reduced to the desired wood moisture content by careful and slow air conditioning.


    In addition, the following load classes must be observed when used:

    exterior space climate

    • The constructive wood protection (rear ventilation, etc. ) must be carried out professionally
    • All cut edges must be sealed (e. g. with Fungol-Hydro-cross-grained wood logo, Aidol cross-grained wood protection or equivalent)
    • Appropriate surface protection must be applied
    • Mounting must be carried out with stainless fasteners.

    outdoor climate I + II
    We explicitly point out that we exclude our three-layer slabs from the use as facade slab in unprotected outdoor areas (outdoor I+II). The use of the slabs in these areas is done at the user's own responsibility and to the exclusion of any warranty claims.