The building cost of new housing constructed averaged R5 908 per square metre in the period January to April this year, resulting in an increase of 3.2% year-on-year on the building cost of R5 724 per square metre in the corresponding period last year.mail Print Share. The building cost of new housing constructed averaged R5 908 per square metre in the period January to April this year, resulting in an increase of 3.2% year-on-year (y/y) on the building cost of R5 724 per square metre in the corresponding period last year.