Common Structural Issues Found During a Home Inspection: What Every GTA Homebuyer Should Know
NOV 18, 2025
Buying a home in the Greater Toronto Area is one of the biggest investments most people will ever make. With high prices across the GTA — Toronto, Mississauga, Brampton, Durham, and York Region — buyers need to be certain they’re making a safe and informed purchase. One of the most critical parts of due diligence is a professional home inspection, especially when it comes to identifying structural issues.
Structural defects are often the most expensive problems to repair, and in severe cases, they can compromise the safety and stability of the entire home. Below are the most common structural problems found during a home inspection — and why they matter.
1. Foundation Cracks
Foundation issues are among the most serious problems discovered during a home inspection. While hairline cracks are normal as concrete cures, larger cracks can signal movement, shifting soils, or water infiltration.
Common warning signs include:
- Horizontal cracks in basement walls
- Step-cracks in brick or block foundations
- Wide vertical cracks (especially >6mm)
- Bowing or bulging walls
- Water penetration or efflorescence
In the GTA, foundation cracks are often caused by:
- Freeze-thaw cycles
- Poor exterior drainage
- Clay soil expansion
- Improper grading
When a home inspector finds these issues, they may recommend structural engineer evaluation. Foundation repairs can range from $2,000 to $30,000+ depending
2. Sagging or Uneven Floors
Homes with sloping or “bouncy” floors often have hidden structural problems underneath. While natural settling is normal in older GTA homes, significant sagging may point to:
Common causes:
- Undersized or damaged floor joists
- Rot from past leaks
- Termite or carpenter ant damage
- Removed load-bearing walls
- Failing support posts or beams
Townhouses and older Toronto homes (pre-1950s) are especially prone to this, since many were renovated without permits. A home inspector will check the basement or crawlspace to confirm whether the structural support is still intact.
3. Roof Structure Problems
The roof’s structure — including rafters, trusses, sheathing, and load distribution — is a critical part of the home’s stability. A standard inspection often reveals issues like:
- Sagging rooflines
- Damaged rafters
- Truss modifications
- Water-stained sheathing
- Inadequate ventilation
Roof structure problems usually stem from:
- Ice damming
- Poor venting
- Past leaks
- DIY modifications during renovations
In severe cases, a failing roof structure can cost $10,000+ to repair. Early detection can prevent further deterioration and expensive repairs.
4. Moisture Intrusion and Rot
Moisture is the enemy of structural components. When water finds its way into the foundation, floors, sheathing, or framing, it can lead to:
- Wood rot
- Mold growth
- Rusted fasteners
- Compromised framing strength
Common sources include:
- Poor grading around the home
- Missing or clogged eavestroughs
- Roof leaks
- Basement seepage
- Plumbing leaks behind walls
In many GTA homes, inspectors find moisture traces with:
- Moisture meters
- Thermal imaging
- Infrared scans
Hidden moisture damage is one of the most expensive issues for buyers because it often requires opening walls, drying structures, replacing insulation, and repairing studs or joists.
5. Load-Bearing Wall Modifications
Open-concept homes are extremely popular in the GTA, especially in older Toronto houses and semi-detached homes. Unfortunately, many of these were renovated without proper engineering work.
Removing a load-bearing wall without adding the correct beam support can cause:
- Sagging ceilings
- Cracked drywall
- Floor deflection
- Structural imbalance between floors
- Long-term settlement
A home inspector will look for:
- Beam installations
- Temporary supports
- Cracks or dips near removed walls
Correcting improper renovations can involve opening ceilings, installing LVL beams, and adding posts — a repair that often runs $5,000–$20,000.
6. Deck and Porch Structural Failures
Decks, porches, and exterior platforms are some of the most common sources of hidden danger. Many GTA decks are built by homeowners without permits or adequate support.
Common inspection findings include:
- Rotting support posts
- Improper ledger board attachment
- Missing flashing
- Undersized beams
- Loose railing systems
Since outdoor structures face weathering, they deteriorate faster. A failed deck can pose serious safety risks. Inspectors frequently recommend repair or replacement when structural elements are compromised.
7. Attic Structural Issues
The attic is often the most overlooked part of a home but contains important structural components. Inspectors routinely find:
- Broken trusses
- Damaged rafters
- Sheathing rot
- Mold growth
- Insufficient insulation
- Animal damage (racoon entry is common in the GTA)
Signs of improper DIY work also show up frequently — like truss cuts to make space for renovations or storage. Compromised attic structure can affect the entire roof system and should never be ignored.
8. Chimney and Masonry Cracks
Brick homes are common across Toronto, and masonry problems are a frequent structural concern. Inspectors often identify:
- Cracked mortar joints
- Spalling bricks
- Leaning chimneys
- Chimney separation from the house
A leaning chimney can be a major safety hazard. Masonry repairs can range from small tuckpointing jobs to full rebuilds.
9. Basement Support Column Issues
In older homes, steel or wooden support columns in the basement may:
- Rust
- Rot
- Sink into deteriorating concrete pads
- Lean from horizontal pressure
Improper or temporary jack posts are another common problem. A certified home inspector will verify that columns are stable, supported on proper footings, and not compromised by corrosion or rot.
Why These Structural Issues Matter
Most cosmetic defects in a house are inexpensive to fix, but structural defects can easily escalate into five-figure repair bills. More importantly, they can pose real safety concerns for your family.
A thorough home inspection helps you:
- Avoid buying a structurally unsound property
- Renegotiate the sale price
- Request repairs before closing
- Make an informed decision
In the GTA’s competitive real estate market, skipping a home inspection can be incredibly risky — especially with older housing stock, aging foundations, and decades of renovations layered over each other.
Final Thoughts
Structural issues are among the most serious and expensive problems discovered during a home inspection. From foundation cracks to sagging floors, roof damage, and moisture intrusion, these defects can significantly impact a home’s safety and long-term value.
If you’re buying a home in the GTA, a professional, certified home inspection is the best way to protect your investment.
