Harper_2016_527 HarperC.R. 2016 527 LeksonS. 1984 280-1 floor building construction earth North America Building floor in one person-hour 0,4 m3 built in 1 p-h p-h var2 / 0,4 m3 var1 * 0,4 It does not include any costs connected to acquiring and transporting material. BuccellatiF. MarkoJ.23.5.2019