Deck Inspection: What’s Important

by | Oct 21, 2022

Wood-framed decks are rather common anywhere you go. These structures provide an outdoor entertainment space that is very popular, especially here in the pacific northwest where we certainly love our exterior activities rain or shine. Unfortunately, one of our predominant exterior weather occurrences is rainwater. Water is the one element that will deteriorate our exterior wooden structures the fastest. This is why an exterior deck inspection from a professional home inspector is of the utmost importance. It is the inspector’s job to point out any structural damage, incomplete installations, wrong fasteners, or moisture-driven wood rot. Deck collapses are not that uncommon, and the inspector needs to let the client know how dependable this structure is, as its failure could have terrible consequences.

Deck Inspection: Wood

During a deck inspection, the inspector should be reviewing both the wood and metal materials for this structure. The wood materials are reviewed for their structural integrity, spacing, species, type (pressure treated vs untreated), and method of installation. If wood materials are splitting, sagging, rotting, or moving, these are all details that should end up in a report. 

Wood rot occurs at an expedited rate if it cannot dry fast enough. Proper spacing between wood treads (3/8ths of an inch) is important to ensure the quickest drying time possible. Knowing what species of wood was installed is important. This usually comes down to pine vs cedar. Pine is a soft wood that will break down at a faster rate than cedar, and cedar carries oils in its grain that resist moisture-related rot as well as wood-destroying insects.

Deck Inspection: Hardware

Reviewing hardware is also a very important portion of this inspection. Hardware refers to the metal connectors and fasteners used to connect the wood materials together. What the inspector is looking for here are the best practices for a deck installation. Using as much hardware as needed to ensure a person’s life is not in danger when atop this structure. Oftentimes, good installation practices are not followed, and this is what we are looking for. We see undersized joist hangers or no joist hangers at all, Nails used instead of threaded lag bolts, undersized bolts used because they are more decorative than hot dipped galvanized lag bolts and washers, and missing metal flashing. 

Joist hangers are intended to be the same height as the dimensional lumber. There are joist hangers for 2x4s, 2x6s, 2×8, and so on. If the joist hanger for a 2×4 is used for a larger board, there isn’t enough connection there to hold the whole board’s height. Also, if the joist hanger, or any other metal strapping, has a manufacturer-provided hole for a nail or screw, all holes must be filled with a nail or screw. Unused penetrations will be called out. When a ledger board is secured to the structure, the ledger board should be held to the house with a properly sized threaded lag bolt. Hot-dipped galvanized is recommended for exterior use, but will not be demanded. If undersized bolts are used, they will be called out. Currently, on the market, there are threaded bolts that are usually painted black with a round bolt head that requires an Allen wrench. These bolts are too thin for the structural integrity of the deck and the assumed live load (refers to people walking on the surface) possibility to ensure the structure won’t move or give way under the strain. Inspectors are also looking for metal flashing that should be installed where the ledger board meets the structure. The purpose of this metal flashing is to prevent rainwater from getting caught between where the wood ledger board meets the exterior of the structure. This moisture will expedite wood rot and reduce the stability of the structural connection to the house.

Why a Deck Inspection is Important

Deck inspections should be taken seriously. The inspector knows the reason this structure was built was to allow people to gather together and socialize on top of it. If an exterior deck gives way under a heavy live load, there could be dire consequences. These specific observations are what make the inspector’s purpose at a home sale so crucial.  

Getting a Deck Inspection with Octopus Home Inspections

If you’re looking for a reliable home inspector in Portland Oregon, be sure to contact our team. We take great pride in helping our customers and we are committed to upholding a strong code of ethics, including professionalism and integrity. Our home inspections are extremely thorough, fairly priced, detailed, and accurate. To better understand our business, check out our 165+ 5-star reviews on google. We look forward to hearing from you.

“It was an absolute joy to work with Chris. He did two inspections for us and his attention to detail was unlike anything I’ve ever seen. My husband and I are first-time home buyers and we are so grateful that he was part of our home-buying experience. Both reports were received within 24 hours and left us feeling significantly more informed and prepared to make important decisions. I am genuinely excited to direct friends and family to him for inspections in the future.”

– Sydney ( 5 Star Google Review)