Floor joists are horizontal structural members that span an open space, often between beams, which subsequently transfer the load to vertical structural members.

Attaching the rim joists, in wall pockets, and cement, or cut and install the floor joists between the rim joists.   Floor joist replacement costs $1,500 on average, typically between $5,000 and $20,000, largest and most complex jobs cost up to $30,000. Expect to pay anywhere from $1500 to $2,000 per joist depending on the extent of the damage and its accessibility to your contractor.