The substrate must be ready for installation, dry, clean and load bearing. If installation occurs on shrinking substrates frequent expansion joints should be included in the layout. In exterior areas apply a contact layer of adhesive mortar and let it set. Prime absorbent substrates in interior areas with Okamul GG or Okatmos® UG 30. Allow drying time of at least 24 hours over calcium sulfate screed or prime with Okamul PU-V schnell. Clean non-absorbent substrates like Terrazzo, ceramic tiles or existing sound and load bearing PVC-coverings with Grundreiniger, grind and clean with heavy duty vaccum cleaner. Then prime with Okatmos® UG 30/Okamul PU-V schnell. Metal surfaces like steel, galvanized steel or aluminum in interior applications have to be form stable (no vibration or flexural stress) and rust free. Remove and grease with aceton and prime with Okatmos® UG 30. Wood substrates have to be dry (moisture content less than 10 %) and thoroughly fixed to the substrate (minimum spacing between screws 15" (40 cm)). Minimum thickness on floors 1" (25 mm), 3/4" (19 mm) on walls. Tongue and groove have to be glued. Allow particle board primed with Okatmos® UG 30 to dry for at least 24 hours.