2020 Average Sagging Floor Repair Cost (with Price Factors)
Deteriorating floor joists or posts. Replacing joists costs around $100 to $300 for each new joist. Floor joists and posts support the flooring, and damage to them is the most common cause of a sagging floor. Deteriorating floor joists, posts, or beams can be caused by termite infestation, water damage, or dry rot.