The Egyptians actually used more limestone blocks on the earlier than on the later pyramids. Simple reason: they were running short of limestone toward the end of their pyramid construction era.
Best estimate on building time for the step pyramid is from ten to fifteen years. Here are some details:
‘[The step pyramid] started off as a mastaba tomb — a flat-roofed structure with sloping sides — and, through a series of expansions, evolved into a 197-foot-high (60 meters) pyramid, with six layers, one built on top of the other. The pyramid was constructed using 11.6 million cubic feet (330,400 cubic meters) of stone and clay. The tunnels beneath the pyramid form a labyrinth about 3.5 miles (5.5 kilometers) long.
The complex
The pyramid is at the center of a complex 37 acres (15 hectares) in size. This complex is surrounded by a recessed limestone wall that contains 13 fake doorways as well as the real colonnade entrance on the southeast side.
A temple lies on the north side of the pyramid along with a statue of the king. The statue is surrounded by a small stone structure known as a “serdab,†his eyes peeking out through a hole. To the south of the pyramid lies a great court, with an altar and stones identified as boundary markers.
A number of facade “dummy†buildings were constructed in the complex, including a series of chapels in the southeast as well as north and south pavilions on the east side of the pyramid. These structures would have served ritual purposes and, curiously, they appear to have been partly buried by their builders, notes Egyptologist Mark Lehner in his book “The Complete Pyramids.”’
The perfect location to store 7 years worth of grain. :-)