Assembly instructions

PRODUCT DESCRIPTION

SWISS KRONO MDF boards are state-of-the-art wood-based products used in the construction industry. Manufactured from natural wood fibres, they are designed for complete construction and insulation of floors, walls and roofs. 
Unlike conventional fibreboard types, SWISS KRONO board is manufactured in the so-called dry process producing board with very high physical and mechanical parameters, while the process itself has no adverse environmental impact.

Thanks to the use of isocyanate PMDI resins, SWISS KRONO MDF board is practically formaldehyde-free.

In addition, they have very low swelling under the effect of moisture.

PROPERTIES OF SWISS KRONO MDF BOARD

SWISS KRONO board is a material open to diffusion. As a result, the board ensures water vapour penetration from the inside to the outside of a building. Free water vapour penetration is determined by the relative diffusion resistance µ, which equals 11 for Kronotec DP 50 and WP 50 types.

The board is thus a perfect wood-based material for outer sheathing of wooden structures, walls and roofs, and makes it possible to design technologically advanced external partitions.

TRANSPORT

SWISS KRONO MDF board should be transported and stored in such a way as to avoid mechanical damage; they should also be protected against direct contact with water.

STORAGE

MDF board should preferably be stored in a closed and ventilated warehouse. It can also be stored under a canopy roof with no exposure to precipitation or ingress of ground water.

BOARD STORAGE ON A CONSTRUCTION SITE

If it is not possible to store the board under a roof, a section of even ground should be provided, e.g. a platform. It should be isolated from the ground with a layer of plastic film and provided with a free access of air.

Appropriate board protection is shown in the following figures:

Before being used on the construction site, boards should be stored in new conditions for at least 24 h.

BOARD TYPES:

  • SWISS KRONO WP – wall board.
  • SWISS KRONO DP – roof board.

APPLICATIONS AND BENEFITS

Wall boards

  • External sheathing of the wall frame.
  • Highly vapour-permeability providing wooden structures with a good protection against moisture.
  • Additional thermal and sound insulation, elimination of thermal bridges.
  • Wall bracing in studwork wall structures.
  • High rigidity of sheathing, especially for boards with index 50.
  • Light, easy and quick to install.
  • Very low swelling under the effect of moisture.

Roof boards

  • Roof sheathing with perfect water evacuation properties thanks to the LiquiSafe joints between boards.
  • ight protection against wind and moisture.
  • Additional thermal and sound insulation, elimination of thermal bridges.
  • High vapour-permeability.
  • As bracing in roof structures.
  • High rigidity of sheathing, especially for boards with index 50.
  • Light, easy and quick to install.
  • Elimination of the need to use roof membranes.
  • Very low swelling under the effect of moisture.

ASSEMBLY OF WALL BOARDS

SWISS KRONO MDF WP can be installed on walls either horizontally or vertically. Compensation gaps of at least 3 mm must be maintained between boards and around door and window openings. 
Boards should be fixed with spiral or ring-shank nails. Nails should be driven every 30 cm on intermediate supports and every 15 cm on board joints. At external wall edges, nails should be driven every 10 cm. The distance between the nail and the board edge must not be smaller than 1 cm. 
Wood bolts or long staples can be used as well.

ASSEMBLY OF ROOF BOARDS

Before installing the roof sheathing, it should be checked whether rafters or trusses are straight, even and arranged along one axis.Bent or uneven rafter affect the final roof appearance. Boards which are wet from the rain must be dried before the assembly of sheathing, e.g. roof tiles on battens. 

Unheated attic space should be well ventilated. Ventilation openings should make up at least 1/150 of the surface plan of ventilated space. 

SWISS KRONO DP roof boards have special tongue-and-groove moulded LiquiSafe edges. This makes the cover structure tight and ensures evacuation of condensate even at roof slopes equal to 15 

If the roof construction has chimney openings, roof sheathing should be at least 12 mm away from the chimney.

The step safety according to Pr EN 12872 for SWISS KRONO DP 50 is:

  • dry board: emax*= 83.3 cm
  • or wet board: emax*= 62.5 cm

where emax stands for the maximum rafter or truss spacing in axes.

When performing assembly works on the roof, workers should stay on the rafter or truss, following OHS regulations in place. SWISS KRONO MDF DP should be fixed with spiral or ring-shank nails. Nails should be driven every 30 cm on intermediate supports and every 15 cm on board joints. At external wall edges, nails should be driven every 10 cm. The distance between the nail and the board edge should not be smaller than 1 cm. 
Wood bolts or long staples can be used as well.