DBV Rainscreen Facade Product Technical Guide
CLADDING MATERIALS
When planning the cladding , in addition to the requirements in terms of protection from the elements , building physics , fire protection and durability , the following points must also be taken into account :
• Type , color and means of fastening ( visible or concealed )
• Joint spacing ( panel size , joint grid , expansion joints , etc .) – the rainscreen facade can , in principle , be installed with open or closed joints
• A joint gap of 5 / 16 " or more should be planned for large-format cladding panels , but this may need to be increased depending on the material and the size of the panels
• Type of substructure
• Reflections from the surface of the material
• Color differences between material lots
• Alignment of the cladding panels
• Junctions and connections to other building parts in accordance with the manufacturer ’ s instructions
All types of cladding require the facade to be divided up into areas . At penetrations in the wall ( e . g . windows ) there may be a need for cladding panels of a different size .
The cladding may be fastened using a visible or concealed system .
The number and type of fasteners to be used depend on static design calculations . The position of the fasteners must be taken into account in the static design calculations and the manufacturer ’ s instructions regarding maximum spacing must be adhered to .
The cladding fastening system must avoid forces of constraint , e . g . through use of fixed and sliding points . Joint gap width must allow for the dimensional changes to be expected , taking the changes in temperature into account .
Drilling and rivet setting gauges should be used in order to avoid forces of constraint in riveted joints .
Forces of constraint are also to be avoided at screw fastened joints through use of a depth gauge , correct tightening torque and screws with a thinner shank that allow the necessary room for movement .
With bonded joints , the joint surfaces must be clean and free of grease . The adhesive manufacturer ’ s instructions must be observed .
Where hanger clip systems are used ( e . g . with hooks , U-bolts or undercut anchors ), possible movement of the substructure and its effects on the cladding panels must be taken into account ( movement of the panels ).
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