Rabbi Kaganoff discusses the prohibition of nichush (superstitious omens) and starts the discussion with the question
“May a frum builder skip the number 13 when naming the floors of a building?”
However, he does not explicitly answer the question. Consider that the clients of this builder, such as renters in an office building or clients in a hotel, would be reluctant to actually rent there. Would this indeed be nichush or would it be a legitimate (and mutar) business decision recognizing that others are superstitious.
An example of this line of reasoning is Yonasan and his armor bearer attacking the Pelishtim Shmuel I 14:8-10. Tosfos and the Ran (Chullin 95b) explain that Yonasan used the "omen" to reassure his armor bearer.
Bottom Line Conjures Up Realty's Fear Of 13
Based on records of buildings with Otis brand elevators, as many as 85 percent of the high rises in the world don't have a 13th floor, says Dilip Rangnekar, spokesman for the Farmington, CT-based elevator maker.