# Crawl Space Structural Repair in Tennessee | Sagging Floors > Crawl space structural repair in Tennessee: sagging floors, failing posts and beams, rotted joists and sills, repair options, and sourced 2026 costs. URL: https://tennesseefoundationrepair.us/crawl-space-structural-repair/ Tennessee Foundation Repair connects Tennessee homeowners with participating contractors for **crawl space structural repair**: the posts, piers, beams, sill plates, and joists that hold up the floor. When those settle, rot, or were undersized to begin with, the floors above sag, bounce, or slope. This page covers the structure. Moisture control such as encapsulation is a related but separate service. ## Signs of crawl space structural problems Most of these show up inside the house first: - Floors that sag, dip, or slope, especially toward the middle of the house. - Floors that feel bouncy or springy when you walk. - Interior doors that stick or swing on their own. - Cracks in drywall above interior doors. - In the crawl space (if you can safely look): leaning or cracked piers, posts sitting on bare soil, soft or crumbling wood, or shims stacked on top of posts. ## What causes crawl space supports to fail Moisture is behind most of it. Damp soil, poor ventilation, and water running into the crawl space soften wood and let rot and wood-destroying insects in. Support piers set on small or no footings can sink into soft soil. Some older houses simply have beams too small or posts too far apart for what they carry, and decades of sagging follow. Any of these can combine with foundation settlement at the perimeter walls. ## Repair options The repair depends on what failed: - **Supplemental supports:** adjustable steel posts or new masonry piers on proper footings under sagging beams. - **Beam repair or replacement:** adding a new beam beside a failed one or replacing it. - **Joist sistering:** fastening a new joist beside a cracked, notched, or rotted one. - **Sill plate replacement:** replacing rotted wood where the house sits on the foundation wall. - **Gradual leveling:** raising sagging floors slowly over time to limit cracking above. - **Moisture control:** drainage, vapor barriers, or encapsulation to keep the problem from returning. Often a separate contractor and scope. ## Structural repair vs. encapsulation Encapsulation lines the crawl space with a heavy vapor barrier and often adds a dehumidifier. It addresses moisture, not structure; it does not hold up a sagging floor. Many contractors offer both, and a good one will tell you which problems need which. Encapsulation may not be included in every referral, so be specific about the problem when you call. ## Safety Crawl spaces can hold standing water, live wiring, sharp debris, and pests, and the structure may already be compromised. Look from the access opening with a flashlight rather than crawling in if anything looks unsafe, and never remove, cut, or jack a support yourself. ## When crawl space supports need a professional look - Floors are getting more uneven over time. - You can see wet, soft, or crumbling wood. - Posts are leaning, cracked, or sitting on bare soil. - There is standing water in the crawl space after rain. - An inspector flagged the crawl space during a sale. ## What crawl space structural repair costs HomeAdvisor's June 2026 crawl space data puts repairs at an average of **$6,000**, with most between **$4,500 and $8,000** and a full range of $250 to $15,000. It lists beam replacement at $1,500 to $5,000 and foundation-related crawl space repairs at $3,000 to $15,000; encapsulation runs $1,500 to $15,000 and is often a separate line item. - **How many supports, beams, or joists need work.** - **Crawl space height:** HomeAdvisor notes spaces under about three feet cost more to work in. - **Rot and insect damage** found once work starts. - **Moisture control** added to the job. ## What you can do right now 1. Note where floors dip or bounce and how that has changed. 2. From the access opening, photograph what you can see; do not crawl in if it looks unsafe. 3. Make sure gutters and downspouts are not sending water toward the crawl space. 4. Do not stack shims or add your own jacks under beams. 5. Call and describe the floors and what you can see below. ## Questions to ask about crawl space repair - What exactly failed: footings, posts, beams, joists, or sills? - What supports will you add, on what footings, and how far apart? - Will you level the floor, and over what period? - What is causing the moisture, and is fixing it part of this quote? - Is encapsulation necessary for the structural repair, or a separate choice? ## FAQ **How much does crawl space structural repair cost?** HomeAdvisor's June 2026 data puts crawl space repairs at an average of $6,000, with most between $4,500 and $8,000. Beam replacement runs $1,500 to $5,000. Encapsulation is separate and can add $1,500 to $15,000. **Why are my floors sagging in the middle of the house?** Mid-house sagging often points to the crawl space supports under the center beam: sinking piers, rotted wood, or posts spaced too far apart. A contractor needs to look underneath to tell which. **Will encapsulation fix sagging floors?** No. Encapsulation controls moisture, which helps protect wood from future rot, but it does not support the floor. Sagging needs structural repair such as added posts, beam work, or joist repair. **Can sagging floors be leveled all at once?** Often they are raised gradually to limit cracking in walls and finishes above. Ask the contractor what level they expect to reach and over how long. **Do I need a structural engineer or a foundation repair contractor?** Sometimes both. A contractor evaluates the house and proposes the repair they install. An independent licensed structural engineer assesses the cause and can specify a repair without selling one; HomeAdvisor puts a structural engineer inspection at $340 to $780. An engineer is worth it for major movement, a sinkhole near the house, a home sale, or contractors who disagree. Referral disclosure: Tennessee Foundation Repair is an independent contractor-referral service. We help connect Tennessee property owners with participating foundation repair professionals. Services are performed by independent contractors. We may receive compensation for qualified referrals. Phone: (865) 276-7293.