You can determine the roof slope yourself in the roof toolbar that appears while drawing the roof. The default value is 33%. (18.26 degrees) You can change this value to the value you want without drawing the roof and draw the roof that way from the beginning. You can use the change roof eaves properties command to change it after drawing. With this command you can change the slope of the entire roof or of some roof surfaces of your choice individually. (in percent or degrees) Good work
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