Sinking Floor Repair in Montgomery, AL

Sinking floors are one of the most noticeable and concerning signs of foundation problems. In

Montgomery, Alabama, where clay soil shrinks during drought and erodes during rain, sinking

floors are common. Understanding sinking floor repair helps you restore comfort and safety to

your home.

Causes of Sinking Floors

Sinking floors occur when the support beneath the floor fails. In slab‑on‑grade homes, the

concrete slab itself sinks as the soil underneath compresses or erodes. In pier‑and‑beam

homes, the floor joists and beams sink because the piers or posts have settled, or the wood

has rotted. The most common cause in Montgomery is clay soil shrinkage during drought,

which creates voids beneath the foundation. Other causes include poor soil compaction during

construction, plumbing leaks that wash away soil, and termite or rot damage to wooden

supports.

Diagnosing the Cause

To repair a sinking floor, we must first identify why it sank. Montgomery Foundation Repair Co

performs a thorough inspection: measuring floor elevations, inspecting the crawl space or

basement, checking for moisture and rot, and testing soil conditions. We also look for other

signs of foundation movement, such as cracked walls or sticking doors. The diagnosis

determines the repair method. For example, sinking from soil shrinkage requires piers; sinking

from rotted joists requires replacing the wood.

Repair Methods for Sinking Slab Floors

For slab foundations, the standard repair is underpinning with steel push piers or helical piers.

We install piers at points along the sinking area, then lift the slab back to level. For minor

sinking (less than 1 inch), polyurethane foam injection may be sufficient to fill voids and lift the

slab. However, foam does not address ongoing settlement risk. Montgomery Foundation

Repair Co recommends piers for any sinking floor that is actively getting worse.

Repair Methods for Sinking Crawl Space Floors

For pier‑and‑beam homes, we first address the support system. We may replace sunken piers

with adjustable steel piers or helical piles. If the floor joists or beams have sagged, we install

new sister joists or use hydraulic jacks to lift and shim the existing ones. If the sinking is due to

rot, we remove the rotted wood and replace it with pressure‑treated lumber. After the structure

is stable and level, we install a vapor barrier and dehumidifier to prevent future moisture

damage.

Frequently Asked Questions