Well completion technology is disclosed for accounting for fracture surface roughness. A frack fluid is pumped into the wellbore to form a fracture in a formation surrounding a wellbore. In one example, a method for completing a wellbore comprises determining a fracture surface roughness for a given formation rock, and for a give fracture fluid or pumping schedule or both, prior to hydraulic fracturing. A fracture fluid and/or a pumping schedule is selected based on the determined fracture surface roughness and formation characteristics. The selected fracture fluid is pumped into the wellbore, with the selected pumping schedule, to create a desired fracture network in the formation.