floor plan professional black line architectural floor plan drawing external dimensions 10 ft x 20 ft high cube shipping container 9 ft 6 in height maintain true rectangular proportions do not alter aspect ratio show container wall thickness accurately open plan layout 6 ft x 6 ft internal bathroom in rear left corner true internal clear dimension includes 36 shower toilet wall mounted sink compact kitchenette opposite bathroom along right wall remaining space open living area front and rear 10 ft access doors indicated windows shown only on left wall continuous skylight shown along right high roof edge dashed overhead line include dimension strings in feet and inches clean builder ready cad style white background black linework only no shading no perspective