Whenever a street or alley is blocked by a building which is being moved, warnings to that effect shall be placed by the movers so as to warn vehicles and persons from entering that portion of the street so blocked. On each night while a building being moved, pursuant to this chapter, remains on the public streets of the City, from dusk to sunrise, the person to whom such permit is issued shall place and cause to be maintained on such building red lights sufficient in number and so located as to adequately protect the public, which lights shall be plainly visible for 100 yards during the period from dusk to sunrise.