To solve the following inconveniences: when a building is constructed, during execution of floor concrete penetrating pipe arrangement work, redundant work steps are carried out and surplus work hours are spent; and during a time period from removal of a void for a floor penetrating pipe to repair of floor concrete with mortar, infiltration of rainwater and fall of chips of a concrete shell, construction materials, etc. can occur via a gap between the floor concrete and the floor penetrating pipe, and therefore work on a lower story is sometimes hindered.

The floor concrete penetration joint is formed in one piece of a pipe joint 1, a mortar repairing resin backing plate 2, a void fixing collar 3, and a fall preventive projection 4, and stuck and fixed into the floor concrete.