Common Deck Defects Found During a Home Inspection: What Homeowners Should Know
A deck is a great extension of your living space—a place to relax, entertain, or enjoy the outdoors. But like any part of a home, decks require proper construction and ongoing maintenance to remain safe and functional.
If you’ve just had a home inspection, your inspector may have identified some concerns with your deck. Don’t worry—deck issues are common, especially in older homes or where DIY construction was involved. The good news is that most deck defects can be repaired or improved with the right information and a solid plan.
This article breaks down the most common deck problems inspectors find and what they mean for you as a homeowner.
Top 10 Common Deck Defects Found During Home Inspections
• Loose or Wobbly Railings
Deck railings are crucial for safety, especially on elevated decks. If the railings move or feel unstable, they may not be properly secured or could be deteriorating. This is one of the top safety hazards found on decks.
• Rotting or Decaying Wood
Exposure to rain, snow, and humidity can cause wooden deck components to rot, especially if not properly sealed or maintained. Rotted posts, beams, or joists compromise structural integrity and can lead to collapse if not addressed.
• Improper Ledger Board Attachment
The ledger board connects the deck to the house. If it’s not properly attached—typically using lag screws or bolts rather than nails—it can pull away from the home over time, increasing the risk of the deck detaching and collapsing.
• Inadequate or Missing Flashing
Flashing is a water-resistant barrier installed where the deck meets the house. Missing or improperly installed flashing allows water to seep in, leading to wood rot, mold, or damage to the home’s structure.
• Unsupported or Undersized Joists
Joists are the horizontal supports that hold up the deck floor. If they’re spaced too far apart or made from undersized lumber, the deck may feel bouncy or sag under weight. This compromises both comfort and safety.
• Improper Footings or Posts
Deck posts should sit on proper footings, not directly on soil or unreinforced concrete blocks. Inadequate support leads to sinking, shifting, and uneven decks—especially in areas with heavy rainfall or freeze-thaw cycles.
• Rusting or Corroded Fasteners
Nails, screws, and brackets can corrode over time—especially in coastal or wet climates. Rusted fasteners lose their strength, increasing the chance of structural failure.
• Loose or Warped Decking Boards
Deck boards can warp, twist, or pull away from the framing over time. Loose boards create tripping hazards, and warped boards can trap water, accelerating decay.
• Inadequate Guardrail Height or Spacing
Modern building standards call for guardrails (on decks typically 30 inches or higher) to be at least 36–42 inches tall, depending on the jurisdiction, with balusters spaced close enough to prevent a 4-inch sphere from passing through. Non-compliant guardrails are both a safety issue and a code violation.
• Poor Overall Construction or DIY Work
Many deck issues stem from amateur construction or repairs that don’t follow good building practices. Lack of permits, improper connections, or shortcuts during installation can create long-term problems that inspectors frequently flag.
Other Deck Issues That May Be Noted in Your Inspection Report
- Improper stair construction or missing handrails
- Surface mildew or mold from poor drainage or lack of sunlight
- Pest damage, especially from carpenter ants or termites
- Cracked concrete footings leading to instability
- Decks built without a permit, raising concerns about compliance
What Should Homeowners Do About Deck Defects?
If your home inspector noted deck concerns, here are some next steps:
- Get a contractor to assess and estimate repairs. Structural defects, especially rot or improper connections, should be evaluated by a licensed professional.
- Fix safety hazards immediately. Loose railings, rotting boards, and missing fasteners should be top priorities.
- Bring your deck up to modern standards. Especially important if you’re selling the home or planning to remodel.
- Consider resealing or refinishing. This helps protect wood from future damage.
- Schedule routine maintenance. Annual inspections and minor touch-ups can prevent bigger issues down the road.
Final Thoughts
Decks are great assets, but they’re also exposed to the elements year-round. Regular inspections—especially when buying a new home—can reveal hidden issues that may not be obvious at first glance. Fortunately, most defects are repairable and well worth fixing for the sake of safety, appearance, and peace of mind.
If you recently had a home inspection and found some of these issues, now’s the perfect time to tackle them and ensure your deck is ready for safe enjoyment.