25%
Of all homes
Have some foundation distress — most is cosmetic or stable
$5,000
Median foundation repair
But range is enormous — $500 to $100,000+
98%
Of basement water problems
Solved by grading and gutter corrections, not interior systems
3
Types of foundation cracks
Only one is typically structural
Foundation Types
Your foundation type determines your failure modes, your maintenance obligations, and what repairs look like.
The type of foundation under your home was largely determined by when it was built, where it was built, and the builder's standard practice at the time. Each type has distinct strengths, weaknesses, and maintenance requirements.
Poured concrete
The current standard in most of North America. A continuous poured wall has fewer joints than block construction, making it inherently more water-resistant. Cracks in poured concrete are common and most are not structural — they result from normal concrete shrinkage during curing or minor settlement that occurred decades ago.
Concrete block (CMU)
Common in homes built from the 1930s through the 1970s. Block walls have mortar joints at every block, creating more potential water infiltration points than poured walls. Block foundations are more susceptible to lateral pressure from saturated soil — bowing or leaning block walls indicate serious structural concern.
Brick foundations
Found in very old homes, typically pre-1920. Brick foundations rely on the integrity of mortar joints. Deteriorating mortar and water infiltration through failed joints are the primary concerns. Repointing is needed every 25–30 years.
Slab foundations
The home sits directly on a concrete slab with no basement or crawl space. Settlement, heaving from expansive clay soils, and plumbing leaks under the slab are the primary concerns. Slab repairs are among the most expensive foundation interventions because accessing the problem requires cutting through the floor.
Pier and beam
The home is lifted on a series of concrete or wood piers with a crawl space below. The crawl space requires moisture management — without vapor barriers and adequate ventilation, wood framing in the crawl space is vulnerable to rot and pest damage.
The foundation industry runs on fear
System Components
Understanding what your foundation resists changes how you read problems.
Footings
The concrete pads or continuous strips at the base of the foundation walls. They spread the load of the structure over a larger soil area and must extend below the frost line to prevent heaving. Most foundation settlement problems originate at the footing level — either inadequate footing size, soft soil below the footing, or frost heave from insufficient depth.
Foundation walls
Transfer the load of the structure down to the footings and resist lateral pressure from the surrounding soil. Lateral pressure is highest in spring when soil is saturated with water. This is why bowing or leaning in basement walls is more common in wet climates and most visible after wet winters or springs.
Drainage systems
Manage the water that reaches the foundation. Exterior waterproofing membranes are the first line of defense. Footing drains collect and redirect water away from the foundation base. Interior drainage systems collect water that gets through the wall and redirect it to a sump pump. Interior systems manage water after it enters — they do not prevent water from entering.
The sump pit and pump
Collect water that reaches the basement floor level and pump it away from the structure. A functioning sump system is the last line of defense against basement flooding. Battery backup is critical — power outages often coincide with the storms that most stress sump systems.
Interior waterproofing is not waterproofing
Failure Timeline
What foundation problems look like over time — and how to tell stable from progressive.
Foundation deterioration progression
New construction
Shrinkage cracks in poured concrete are expected and typically not structural. Settlement cracks at corners of openings are common. Document everything with photos and dates.
Early monitoring
Check documented cracks annually. A crack that hasn't changed in years is almost certainly stable. Ensure grading and gutters are directing water away from the foundation.
Active assessment
Block foundations may need mortar repointing. Exterior waterproofing membrane may be deteriorating. Any new cracking or crack progression warrants evaluation.
Professional evaluation
A structural engineer evaluation is warranted as a baseline even if no visible problems exist. Footing depth and condition relative to current code is worth understanding.
Immediate evaluation
Cracks that are visibly growing, doors and windows increasingly difficult to operate, or floors with increasing slope indicate active movement requiring immediate structural engineer evaluation.
Inspection
How to read foundation cracks and what actually warrants concern.
The three types of foundation cracks
Hairline cracks (less than 1/16 inch) in poured concrete are almost universally the result of normal concrete shrinkage during curing. They're cosmetic. They can be sealed to prevent water infiltration but they don't indicate structural distress.
Diagonal cracks running from the corners of windows and doors at roughly 45 degrees are settlement cracks. They're extremely common and usually indicate minor differential settlement that happened years ago and has been stable since. The key question is whether they're growing — mark the ends with a pencil and date, then check again in 6 months.
Horizontal cracks in basement walls — especially in block foundations — are the most serious type. Horizontal cracking indicates lateral pressure from soil is overcoming the wall's resistance. This is a structural concern that warrants professional evaluation. Do not ignore horizontal foundation cracks.
Outside the home
Walk the full perimeter and check that the soil slopes away from the foundation — at least 6 inches of drop in the first 10 feet. Check that downspout extensions are directing water well away from the foundation. These two items resolve the majority of basement water problems and cost almost nothing to address.
Who to Call
The most important thing to know about foundation repair — get a structural engineer first.
The foundation repair industry is structured in a way that creates a conflict of interest: the companies that diagnose foundation problems are the same companies that profit from fixing them. This doesn't mean they're dishonest — but it means you should not take a foundation repair company's assessment as an objective engineering opinion.
Get a structural engineer first
A licensed structural engineer (PE) charges $300–600 for a foundation evaluation. Their fee is not contingent on finding problems. Their assessment is what you use to evaluate any repair recommendation. This is the single most important step before spending money on foundation work.
What foundation companies are good at
Once a structural engineer has identified a legitimate problem and specified a repair approach, foundation companies are the right contractors to execute that work. Use the engineer's report to get competitive bids from multiple contractors.
Questions to ask any foundation contractor
"Can you provide a written report specifying what you found, what's causing it, and what the repair addresses?"
A legitimate foundation company can provide a written assessment. Verbal-only recommendations with immediate pressure to sign are a significant red flag.
"Is this crack or movement stable or progressive? How are you determining that?"
The distinction between stable and progressive is the most important foundation question. A company that can't explain how they're making this determination hasn't actually assessed it.
"Does this repair address the cause of the problem or manage the symptoms?"
Interior drainage systems manage water after it enters. Grading corrections prevent it from reaching the foundation. You need to know which category a proposed repair falls into.
"Have you reviewed a structural engineer's report for this property?"
If you've obtained an engineer's report, ask whether the proposed repair aligns with the engineer's recommendation. Any significant divergence warrants a direct conversation about why.
"What warranty do you provide, and what does it cover specifically?"
Foundation repair warranties vary enormously. Understand exactly what's covered, for how long, and whether the warranty transfers to a future buyer of the home.