The elevations of residential buildings for middle class in Heliopolis area was affected with many design directions during five periods from the 20th century to the beginning of the 21th century. The first and second periods in the first half of 20th century were affected by the Europian designs at this time, the trend was going to revive the historical models, as well as to the direction of modern architecture, the most important architectural configuration attributes in this period is interest in aesthetic values and decorations of the westward civilization. The third period in the second half of 20th century and after the July Revolution in 1952, the elevations designs turned to high apartment buildings and were similar in outer shape. Then the fourth period in the end of 20th century, the construction sector saw a big mutation as a result of the spread of the new construction materials, and had a tendency to exotic designs, so there were many directions for residential buildings elevations in this period don't achieve human values or environmental or occupational standards. Finally the fifth period in the beginning of the 21th century, the decorations and ornaments and cornices returned to appear again with a lot of quotation from the classic of Western models. So it was necessary to learn the most important architectural design basics and aesthetic standards for the residential buildings elevations in Heliopolis area and examine their compatibility with the surrounding environment, so that we can achieve a beter felling of satisfaction and happiness into the people who see and visit this buildings. So we choose (Baghdad Street) in Heliopolis because it contains many architectural styles that shows clearly the environmental impacts on the residential buildings elevations during the 20th century until the beginning of 21th century.