Foundation Repair Glossary: Key Terms Explained
Foundation repair comes with its own vocabulary, and it’s easier to make good decisions about your home when you understand what the terms actually mean. This glossary covers the words and phrases you’re most likely to hear during an inspection, from soil and construction basics to the specific repair systems Foundation Solutions installs.
A
Aggregate
The sand, gravel, or crushed stone mixed with cement and water to form concrete.
Alluvial Soil
Soil deposited by moving water, such as a river or stream. It’s often loose and prone to settlement, making it a common contributor to foundation settlement.
B
Basement Wall Crack
A crack in a poured concrete or block basement wall. The pattern — vertical, horizontal, or stair-step — points to a different underlying cause. See our full basement wall cracks guide.
Bearing Capacity
The maximum load soil can support without excessive settlement or shear failure.
Bearing Soil
Soil capable of supporting the weight of a foundation without significant compression or shifting.
Bowing Wall
A basement or foundation wall that curves inward due to soil pressure from outside — a sign the wall needs stabilization. See bowed basement walls.
Brick Veneer
A single layer of brick attached to a home’s exterior for appearance, not structural support. Cracking here often reflects movement in the structure behind it — see cracking in brick walls.
C
Carbon Fiber Reinforcement
High-strength fabric straps bonded to a foundation wall with epoxy to stop cracking or minor bowing from progressing further. See carbon fiber repair.
CMU (Concrete Masonry Unit)
A standardized concrete block used in block foundation construction. Cracking typically follows the mortar joints between units — see cracked block foundation.
Concrete Footing
The wide base of concrete beneath a foundation wall that distributes the structure’s weight into the soil.
Concrete Lifting
A repair method that raises a settled concrete slab back toward level, typically using mudjacking or polyurethane foam. See concrete lifting.
Cove Joint
The seam where a basement floor slab meets the foundation wall, formed because the two are poured separately. A common point of water entry.
Crawl Space
A shallow, unfinished space beneath a home, typically 1 to 4 feet tall, used for access to plumbing, wiring, and ductwork. See crawl space repair.
Crawl Space Encapsulation
Sealing a crawl space with a heavy vapor barrier to block moisture, humidity, and pests from the space.
D
Differential Settlement
Uneven sinking of a foundation, where one section settles more than another, causing most of the visible cracking and structural stress homeowners notice. See foundation settlement.
Downspout
The vertical pipe that carries water from a gutter down and away from the house — a common contributor to foundation problems when it discharges too close to the home.
Drywall Crack
A crack in interior wall or ceiling drywall. Most are cosmetic, but certain patterns point to foundation movement. See drywall cracks.
E
Efflorescence
A white, chalky mineral deposit left on concrete or block surfaces after water evaporates — a common sign that water has been passing through a wall.
Expansive Soil
Clay-rich soil that swells significantly when wet and shrinks when dry, one of the leading causes of foundation movement.
Excavation
Digging to expose a foundation wall or footing, typically required for exterior repair or waterproofing work.
F
Floor Joist
A horizontal framing member that supports a floor from below. Damaged or sagging joists cause soft, springy, or uneven floors. See floor joist failure.
Footing
See Concrete Footing.
Foundation Underpinning
A repair method that extends a foundation’s support down to stable, load-bearing soil, typically using piers. See foundation underpinning.
Free Inspection
A no-cost visit from a project manager to assess a foundation issue and recommend a repair plan.
G
Grading
The slope of the soil around a home. Proper grading directs water away from the foundation instead of toward it.
Groundwater
Water located beneath the surface of the ground, which can build up hydrostatic pressure against a foundation wall.
H
Helical Pier
A steel shaft with helical plates that is screwed into the ground to a load-bearing depth, then connected to a foundation to stop settlement and lift it. See helical piers.
House Leveling
Raising a settled or sunken structure back toward its original, level position. See house leveling.
Hydrostatic Pressure
The force exerted by water-saturated soil against a foundation wall — a leading cause of bowing and horizontal foundation cracking.
I
I-Beam
A steel beam, shaped like the letter I in cross-section, used in wall repair systems to brace a bowing basement wall.
Injection (Crack Injection)
Filling a wall or floor crack with epoxy or polyurethane to seal it against water intrusion.
L
Lateral Pressure
Sideways force, usually from soil or water, pushing against a foundation or retaining wall.
Load-Bearing Wall
A wall that supports the structural weight of the building above it, as opposed to a wall that only divides space.
M
Mortar Joint
The layer of mortar between individual bricks or blocks. Deterioration here is a common starting point for masonry wall cracking.
Mudjacking
An older concrete-lifting method that pumps a cement-based slurry beneath a slab to raise it. See how it compares on our polyurethane foam jacking page.
N
Nail Pop
A small bump or protrusion in drywall, or an exposed nail head in a wood floor, caused by lumber shrinkage or, less often, structural movement. See drywall and floor nail pops.
P
Parging
A thin layer of cement-based coating applied to a foundation wall for a smooth, finished appearance.
Perimeter Drain
A drainage system installed around the interior or exterior base of a foundation to collect and redirect water.
Pier
A vertical support column, driven or drilled to stable soil, used to stabilize or lift a foundation. See helical piers and push piers.
Point Load
A concentrated weight applied to a specific spot on a structure, such as a support column, that the framing must be sized to handle.
Polyurethane Foam Jacking
Injecting an expanding two-part foam beneath a slab to lift it, faster and lighter than traditional mudjacking. See polyurethane foam jacking.
Push Pier
A steel pier driven hydraulically into the ground beneath a foundation, using the structure’s own weight for resistance, then used to stabilize and lift it. See push piers.
R
Rebar
Steel reinforcing bar embedded in concrete to add tensile strength.
Retaining Wall
A structure built to hold back soil on a sloped lot. When it leans or bows, it needs stabilization separate from the house foundation. See retaining wall stabilization.
S
Sagging Floor
A floor that dips or feels bouncy underfoot, typically caused by weakened or damaged floor joists. See floor joist failure and uneven floors.
Sistering
A repair technique that attaches a new, structurally sound joist alongside a damaged one to restore strength.
Slab Foundation
A foundation type consisting of a single concrete slab poured directly on the ground, with no basement or crawl space beneath it. See cracked foundation concrete slab.
Spalling
Flaking, chipping, or crumbling of a concrete or masonry surface, often caused by moisture and freeze-thaw cycles.
Stair-Step Crack
A crack that follows the mortar joints of a brick or block wall in a zigzag pattern — a classic sign of foundation settlement. See cracking in brick walls.
Structural Engineer
A licensed engineer who evaluates and certifies the structural integrity of a building, sometimes required for permitting or insurance purposes.
Sump Pump
A pump installed in a basement or crawl space to remove water that collects in a sump pit, keeping the space dry.
T
Tuckpointing
Repairing or replacing deteriorated mortar joints in a brick or block wall.
U
Underpinning
See Foundation Underpinning — learn more.
Uniform Settlement
When an entire foundation sinks evenly, as opposed to differential settlement. Generally less structurally damaging, but can still affect drainage and utility lines. See foundation settlement.
V
Vapor Barrier
A layer of material, usually plastic sheeting, used to block moisture from passing through a floor, wall, or crawl space.
Vertical Crack
A crack running up and down a foundation wall, usually from concrete shrinkage and typically less serious than a horizontal crack. See vertical foundation crack and vertical basement cracks.
Void
An empty gap or cavity in the soil beneath a slab or footing, often caused by erosion, that leaves the concrete above unsupported.
W
Wall Anchor
A steel plate and rod system anchored in stable soil outside a home, used to gradually straighten a bowing basement wall. See wall anchors.
Wall Repair System
A steel I-beam bracing system installed against a basement wall to stop a moderate bow from progressing. See wall repair system.
Waterproofing
The process of preventing water from entering a basement or crawl space through cracks, joints, or porous walls.
Weep Hole
A small opening left in a wall or retaining structure to allow trapped water to drain out.
Still Have Questions About Your Foundation?
Whether you’re just learning the terminology or ready to talk through a specific problem, our local team is here to help. Reach out for a free inspection and a plain-language explanation of what’s going on with your home.
Testimonials
I don't even know where to start with this review. From the first contact to the end of the job, Ryan and his crew were amazing - professional, knowledgeable, courteous, tidy and clean and very respectful of the impact the job had on me as the homeowner. The job was major, but I felt confident with the information that Ryan and his crew shared with me each step of the project. Since they are specialists, they are very busy so it took a while from start to finish but worth the wait! I could not be more pleased. They get an A+++ from me.
We had a consultation with a very knowledgeable engineer (Collin) who's extremely patient to answer questions and concerns we had. After a thorough walkthrough and measurements, it turned out the area which we thought might be problematic with leveling is only centralized and minuscule, not foundation-related. I'd like to thank Foundation Solutions for this engineer's detailed explanations, professional knowledge and recommendations. At the end, we acquired peace of mind and would highly recommend this company to anyone that may be seeking help with foundation related issues. If we are doing any addition/expansion of our house, we would definitely get in touch again for securing our foundation.
Kyle and the team are awesome! A corner of our foundation has a horizontal crack and when we go out for a quote, many companies explained how serious it is and give us a high estimation. Kyle came onsite and did a detailed inspection, explain why it crack, and how to properly fix it. Then few days later, gave us a reasonable estimate, and we decided to go with the service, they handled the permit, came to fix it in a day and did all the final inspection and passed, we have a smooth experience on the fix. My family are super happy with their service and already recommend to friends in case they need some work in the foundation.