Expert Foundation Repair Services In Wilmington, NC

Soil movement is a widespread problem on the coast of North Carolina. Unfortunately, homeowners in Wilmington and the surrounding area are at high risk of foundation damage as a result.

There are several factors that create problems for home foundations in Wilmington. We’ll discuss these in-depth below and include some information on the type of damage each can cause.

Sandy Loam Soil

The soil in Wilmington is mostly Norfolk fine sandy loam and Portsmouth fine sand. All dirt is comprised of sand, clay, and silt. As the names of the soils in this area suggest, they both have a high ratio of sand to the other constituents. Typically, sandy loam soil is ideal for construction because it doesn’t swell or shrink as clay soil does; however, it can still be hazardous for homes built on it.

Wilmington’s soil has excellent drainage, but it is at risk of erosion as runoff moves through the earth. As such, water in the ground can erode portions of your property, sometimes creating voids or loose patches of dirt. Under the weight of your entire home, the soil can settle, leaving your foundation without the support it needs.

This settling can occur at varying rates under your house, leading to a process called differential settling, where sections of your home sink more rapidly than others. Differential settling eventually leads to areas of your foundation cracking and falling away from the rest of the foundation. It can cause severe structural damage over time, as your house relies on its foundation for a level and supportive base.

Ground erosion also occurs most readily where the earth meets your concrete, so runoff movement can create voids around your concrete block walls. Water can collect in these voids and be exposed to your foundation for extended periods, typically leading to water intrusion into your crawlspace or basement.

Above-Average Rainfall

Wilmington experiences around 55 inches of rain annually, about 50% more than the national average. Heavy rainfall contributes to the issues present because of the soil content and risk of erosion.

More runoff means a higher chance of the ground around your foundation eroding, and it also fills the voids near your concrete more readily, leaving your basement or crawlspace open to water damage and moisture build-up.

Tropical Storms

The coast of North Carolina, including the Wilmington area, is open to hurricanes and tropical storms, experiencing an average of around two every year. While most don’t hit land, the wind and heavy rainfall can present a problem for your home’s foundation.

Rain can be detrimental to concrete, but excessive, concentrated rain that is common during tropical storms can be devastating over time. High rainfall in a short amount of time creates a higher risk of ground erosion, differential settling, and water intrusion, as it leaves runoff in contact with your foundation walls for extended periods.

High, Year-Round Humidity

Lastly, Wilmington’s high humidity causes moisture build-up that can quickly damage foundations and the rest of your home. The city experiences an average humidity between 70% and 80%, and while basements and crawlspaces are naturally prone to moisture issues, the humidity in the city makes the problem significantly worse. Moisture creates several issues for your foundation.

Since basements and crawlspaces are underground, they’re naturally cool and dark. Moist air in that environment creates the perfect conditions for mold growth. Mold in your basement not only decreases the quality of the air in your home via a process called the stack effect, but some strains can feed on the building material under your house. This can gradually weaken the concrete, floor joists, or framing that give your home structure and support.

Additionally, moisture naturally attracts rodents and insects. Pest infestations can be a nuisance to deal with, but certain insects can cause structural damage to your home. Termites and carpenter ants feed on wood and can destroy the framing or support beams in your house.

There are numerous signs you may notice in and around your house in Wilmington that signify foundation damage. We’ll discuss each of the most prevalent symptoms below and what type of foundation problem each one typically indicates.

Foundation Cracks

Foundation cracks can be a bit tricky to diagnose because the location and orientation matter greatly. Some gaps are unavoidable and don’t indicate significant damage, while others could predict severe issues and structure collapse. We’ll break down the common cracks by location below.

Hairline Floor Cracks

All concrete foundations settle during the first few years after they are poured, and most develop thin cracks in the slab during that time. Provided they remain thin and don’t continue to worsen, these cracks are usually created by the natural settling process and aren’t a significant problem. Most Wilmington homeowners have them sealed to stop water from entering through them.

Wide or Unlevel Floor Cracks

Cracks in your slab that grow in width to over ⅛” or that become unlevel from one side to the other, your foundation is likely suffering from differential settling. This is a common occurrence in Wilmington, given the sandy soil and the high rate of erosion from the above-average rainfall in the area.

These types of cracks typically indicate structural damage and should be stabilized by a concrete repair specialist as quickly as possible.

Vertical Wall Cracks

Cracks running vertically on your concrete block walls usually occur because of natural settling as well. Gaps under ⅛” thick can often simply be sealed with epoxy or polyurethane to keep water out, and broader gaps may need some minor stabilization to prevent further growth.

Horizontal Wall Cracks

Gaps running horizontally on your wall indicate excessive hydrostatic pressure from the soil outside your crawlspace or basement walls. Although these fissures are more prevalent in areas with clay soil, they can occur in Wilmington if the ground erodes around your foundation and the voids fill with water.

These cracks signify structural damage and require structural repair immediately.

Stair-Step Cracks

Stair-step cracks form on your concrete block wall in a step pattern in response to differential settling. As a section of your foundation loses support from underneath, it cracks away from your home and sinks into the earth. These cracks necessitate immediate structural repair, as they can lead to total foundation failure if left untreated.

Bowing Foundation Wall

Bowing of your foundation wall typically appears before a horizontal crack forms. Hydrostatic pressure from wet soil or water against your concrete causes the wall to bulge inward. This symptom should be addressed quickly, as it indicates structural issues and will often worsen if left untreated.

Moist or Wet Basement or Crawlspace

Lastly, one of the most common signs of foundation damage in Wilmington is moisture or water in your basement or crawlspace.

Liquid water under your home can often be identified by puddles on the floor, wet spots on your concrete walls or slab, or water visibly trickling in through foundation cracks, especially during heavy rainfall.

Moisture under your house can be a bit more challenging to detect. You may only notice damp air or musty odors when entering the area, which isn’t always obvious. Sub-optimal moisture conditions might also simply result in poor air quality in your home, including uncomfortable temperatures or mold spores that can cause unexplained allergic reactions.

More obvious signs of moisture under your house include visible mold growth on your concrete, pest infestations, and efflorescence, which is an accumulation of white salts and minerals on your basement walls after intruding water evaporates into the air.

Homeowners in the Washington, D.C. area who experience foundation movement typically find cracks in their foundation walls and on their slabs.

Other signs of damage can appear throughout your living space, including uneven or buckling flooring, fissures in your sheetrock around wall openings or room corners, cabinets and countertops separating from the walls behind them, and doors and windows sticking and becoming difficult to open or close.

The water and moisture issues prevalent in D.C. are usually most evident in your crawlspace or basement.

You’re likely to find efflorescence or staining on the walls, mold growth, musty smells, water damage, water visibly leaking through foundation cracks, damp air, and signs of pest infestation. Many homeowners also notice non-seasonal allergy symptoms in their house, uncomfortable air temperatures, and above-average utility bills.

Property owners in Wilmington typically pay around $4,500 for foundation repair services, but the total cost can range from several hundreds of dollars to $15,000 or more. We’ll provide some project-specific pricing below to give you the most accurate estimate for your home.

Cost to Seal Foundation Cracks

Cracks in your foundation that aren’t deemed to be structural can usually be sealed to prevent water or moisture from getting through them. Most contractors in Wilmington charge between $250 and $750 for this service, depending on the size of the gap.

Cost to Fix Horizontal Cracks or Bowing Walls

Inward bulging of foundation walls and the eventual horizontal cracks it causes typically require earth anchors for stabilization. The anchors cost approximately $1,000, and most walls need three to five anchors. The total project cost will be around $3,000 to $5,000.

Other contractors opt for carbon fiber support strips for bowing walls, which help prevent further inward movement. This minor repair costs approximately $2,000, but the price can fluctuate based on how many strips you need.

Cost to Fix Stair-Step Cracks or Uneven Floor Cracks

Step-shaped cracks or wide or unlevel floor cracks that are caused by differential settling usually necessitate underpinning. Foundation repair specialists will use push piers to provide support to the underside of your foundation.

Steel piers cost around $1,000 each, while helical piers – which are more common in Wilmington – cost about $3,000 each. Your total cost for this basement or crawlspace repair can range from around $3,000 to $15,000 or more, depending on the extent of the damage.

Some foundation contractors fix minor settling with mud jacking, a form of concrete leveling. This process costs around $2,000, but it isn’t a permanent solution, so it rarely comes with a warranty.

Cost to Prevent Water Intrusion

Water intrusion is a prevalent problem in Wilmington because of the soil consistency and heavy, concentrated rainfall. Basement waterproofing systems can include various solutions, including vapor barriers, sump pumps, dehumidifiers, exterior drainage systems, crawlspace encapsulation, and more.

Most homeowners in Wilmington pay an average of $6,000 for a complete waterproofing system.