When assessing foundations, it’s helpful to understand their purpose and the common types you’ll encounter. A home’s foundation supports the entire structure, transferring the weight of the building to the ground. It must be level, sturdy, and able to withstand environmental forces like moisture, temperature fluctuations, and soil shifting.
- Basement foundations- Found predominantly in colder climates, these are made of poured concrete walls extending below ground level to form a basement.
- Crawl space foundations- A wood-framed or concrete structure that elevates the home a couple of feet above the ground, creating a crawl space underneath.
- Slab foundations- A single layer of concrete poured directly onto the soil, often used in warmer climates.
Assessing a foundation’s condition
- Exterior cracks
Some hairline cracks in the foundation walls or floor are normal due to concrete curing and minor settling. However, larger cracks – over 1/4 inch wide – could indicate more severe structural issues and should be inspected.
- Interior cracks
Look for cracks along walls, ceilings, floors, windows, and door frames inside the home. These signify foundation settling or upheaval from soil movement.
- Soil and drainage considerations
A foundation resting on stable, well-compacted soil that doesn’t significantly expand or shift when exposed to moisture. Problematic soil types include expansive clays, untreated fill soil, and loose, sandy compositions.
- Soil grading
Proper grading – the slope of the soil around the foundation – is essential for diverting water away from the home. You want a gradual slope angling down at least six inches over four feet from the foundation.
- Trees & shrubbery
Deep-rooted vegetation like trees and large shrubs planted too close to the foundation can disrupt drainage and cause soil movement, leading to costly damage over time.
- Gutter systems
Well-functioning gutters and downspouts are key for directing rainwater away from the foundation and preventing erosion. Look for signs of improper drainage, like water pooling around the base.
- Keeping water at bay
Water is arguably a foundation’s biggest nemesis. Excess moisture gradually deteriorate concrete and enable structural shifting. Watch for these potential problem areas:
- Poor exterior grading
As mentioned above, soil should slope away from the foundation to prevent water accumulation.
- Roof & window leaks
Inspect the roof, windows, and other entry points for any leaks allowing water intrusion that could affect interior footings.
- Faulty plumbing
Unseen plumbing leaks around bathtubs, showers, or pipes underneath the home slowly seep moisture into the foundation over time.
- High water tables
Homes built in areas with high groundwater levels are at increased risk of hydrostatic pressure and moisture penetration into the foundation check out the post right here about the building inspections Sydney.
- Clogged weeping tiles
Many basement foundations include drain tiles (weeping tiles) around the footings to divert groundwater. Debris buildup in these tiles leads to water backup and foundation issues.
Signs of serious foundation problems
While some foundation quirks are normal byproducts of a house settling into its environment, other indicators point to potentially severe structural failures that require professional evaluation and repairs. Some major red flags include:
- Large horizontal cracks in foundation walls wider than 1/4 inch
- Exterior foundation bulging or leaning inward
- Interior walls or floors exhibiting major cracks or unevenness
- Doors and windows becoming severely stuck or failing to latch
- Portions of the foundation separating from the structure
If you notice these worrisome symptoms, it’s critical to have a structural engineer inspect the home. Major foundation repairs like underpinning, piering systems, or entire foundation replacements become exorbitantly costly. Conducting thorough due diligence upfront could save you from an unstable – and unsafe – investment.