Deck Inspection Checklist: A Full Guide to Deck Safety

Making sure your deck is safe and sound is an important task for a homeowner. While your deck is undoubtedly your default outdoor oasis for everything from morning coffee to backyard birthday barbecues, the reality is that a deck is a liability. Luckily, having the right deck inspection checklist can help you avoid hazards while keeping your favorite spot beautiful and durable for years to come!

Before You Inspect Your Deck

A full-scale deck inspection should be done at least once a year. Whether you built your own deck recently or inherited an older deck when purchasing a home, local codes are important. Consider getting a copy of your town or city's deck coding regulations to consult as you work your way through a deck inspection checklist. This can help to ensure that any updates or repairs you make based on your inspection findings will be compatible with the latest rules.

1. Wood Decking Boards

Serving as the "surface" portion of your deck, decking boards endure lots of wear and tear. The biggest threat to wood decking is moisture. Here's what to look for with traditional deck boards:

• Splintering and cracking: Depending on the severity, you may be able to either utilize wood glue to resolve surface-level issues or sand and refinish boards. The cost to stain a deck after sanding down the whole thing may be worth it if enough boards are splintered or fading.

• Rotting boards: This indicates water damage. Generally, boards will need to be replaced.

• Mold: Mold can be furry, slippery, black, grey, or green. It's caused by rain and dew interacting with organic material. Depending on the severity, mold can often be treated with household dish detergent, bleach, or pressure washing.

• Insect damage: Look for signs of termite damage that could indicate an infestation. If it's apparent that termites have moved in, you may need to extend the inspection to your whole home.

• Loose nails: Loose or protruding nails should be secured to avoid injury to people and pets.

• Warped boards: Warped and bowed deck boards can often be fixed by being re-nailed.

Considerations for Composite Decking

Decks with composite deck boards are generally easier to inspect because "wood rot" issues are nonexistent. This means you don't need to worry about water damage and mold. However, composite decking still requires inspection. If your deck material is composite, your main concerns will be loose or damaged fasteners, damage from impact, and sagging. Sagging in composite deck boards can be a sign of product defect or improper installation. That means you'll need to get your warranty out if you suspect that something is amiss!

2. Deck Railings

After inspecting deck boards, it's time to move up to deck railings and guardrails. Local codes will determine if your deck requires railings. Generally, decks 20 to 30 inches above ground require railings. Your inspection approach for deck railings will differ based on whether you have metal or wood railings. If you have wood, look for signs of rot and insect damage that could indicate that railings need repair or replacement. If you have metal, look for any signs of rust or peeling that could pose dangers to someone who puts their hands on the rail. Here's the general deck railing checklist for railings made from any material:

• Look for rusted or loose fasteners and screws.

• Ensure that all balusters are intact and secure.

• Check any built-in rail lighting to ensure that it's working properly.

• Apply pressure to guardrails to see if they shift or bend.

• Check the spaces between balusters to ensure that they are less than 4 inches apart to ensure that children cannot squeeze through.

3. Deck Stairs

This step can obviously be skipped if you have a ground-level deck. For an elevated deck or two-story deck, secure and properly maintained stairs are essential for safety. Like the rest of a wood deck, stairs are vulnerable to decay which can cause instability and shifting over time. Here's what to look for:

• Signs of rot or pest damage

• Loose railings

• Missing railings or balusters

• Rough spots or splintering that can lead to injury

• Worn or warped treads

• Rusted or loose fasteners and nails

• Excessive "squeaking" sounds that indicate wear and tear or instability

• Bowed, warped steps

• A loose or weak stringer that attaches the deck to the stairs

• If accessing the deck via stairs is challenging, consider utilizing some tips for wheelchair accessibility at home when making changes to your deck stairs

4. Deck Flashing

Flashing plays an essential role in preventing water damage for your home and deck. Flashing refers to an L-shaped metal piece that diverts water away from the home's foundation. You can locate it on top of your ledger board. Flashing needs to be replaced if you notice that it's worn down or full of holes. If you discover that whoever built your deck failed to use flashing, it needs to be installed right away. Other things to look for include:

• Water stains below flashing

• Trapped debris

• Rot in the area between the header and flashing

• Signs that your current water drainage system isn't working

5. Deck Brackets

Deck framing brackets include a wide variety of hardware pieces. The most commonly used ones are joist hangers, "T" brackets, and "L" brackets. A deck bracket essentially refers to any metal hanger or plate that is used to connect two pieces of wood: Here's how to inspect deck framing brackets:

• Ensure that the nails being used are the proper shape and size for each hole

• Look for signs of rust that can weaken brackets

• Check that brackets are securely in place

• Ensure that brackets are not bent

6. Deck Substructure

A deck's foundation and substructure are vulnerable to rot and decay because components are much closer to the ground compared to the walking surface of the deck. In some cases, part of your deck substructure may even be buried. If significant parts of your substructure are compromised, it may be time to look into deck replacement cost instead of making repairs. Here's what to look for during a deck substructure inspection:

• Look at the outside board called the rim joist to ensure that it's still attached to the deck floor. Confirm that all nails and hangers are secure

• Ensure that concrete footings are secure and stable

• Check for rot in all wood posts and joists. "Spongy" wood is indicative of severe moisture or termite damage

• Look for general signs of rot, rust, and weathering along all components

• Look for ledger board separation

How Much Does Professional Deck Inspection Cost?

If you suspect your deck isn’t in good shape, hiring a pro to do a deck inspection can cost from $25 to $200. Some deck pros will bundle that cost into the total repair estimate, depending on the extent of damage. Alternatively, you may have your deck looked over as part of your full home inspection, which costs an average of $345. 

DIY vs. Hiring a Pro

In most cases, a proper deck inspection requires a professional with plenty of experience and knowledge of the local building codes. If you're overwhelmed by the architectural and structural know-how needed to do a deck inspection, don't despair. The safest way to detect issues with a deck early enough to get them fixed is to hire local deck builders offering deck inspection services.