Pressure-treated wood can rot!
People think their pressure-treated wood decks will never rot.
Another urban legend rears its ugly head.
The first pressure-treated wood was invented by Dr. Karl Wolman in the early 20th century. He developed a water-based process to infuse salts into the wood that would displace the sap and thereby preserve it. And he tweaked his formulas and techniques for decades.
From that start his chemical process went to a CCA liquid - Chromated Copper Arsenate - which was a mixture of copper sulfate and arsenate chromate dissolved in water. Similar chemical mixes were used for decades. In the United States the arsenate (a form of arsenic) was removed from pressure-treated wood formulas in 2004.
This deck was built in the late 80s. It probably used a CCA then. However, there are different uses and grades of pressure-treated woods. For example, stamps can be seen which say things like UC4A (Ground Contact, General Use) and UC4B (Ground Contact, Heavy Use). While it's unknown what grade wood was used for this deck, it could very well be that the common parlance of the era, at hardware stores and used by contractors, was that the wood would last forever.
Of course, that isn't true. This post is rotting and/or damaged by termites. It is compromised. The rest of the deck columns were compromised as well, with severe splits, cracks, huge splinters and warping. It is basically unsafe. Walking out onto the very damaged deck, it could truthfully be said that it isn't "rotting!"
My recommendations: due to urban legends people sometimes accuse home inspectors of making things up. This homeowner was upset that I had made something up just to put it on the inspection report! We don't make things up on home inspection reports! The house is the house, the condition is the condition, and those things are observed and reported by the inspector. And it might be worth a smidge of an attempt at trying to understand the report and actually LOOKING at the photos therein to see what the home inspector is saying! Anything less than basic understanding a home inspection report prior to accusing anyone about it is lazy and counterproductive. Oh, and remember this news flash: Wood decks don't last forever. Pressure-treated wood can rot!
Jay Markanich Real Estate Inspections, LLC
Based in Bristow, serving all of Northern Virginia.
Office (703) 330-6388 Cell (703) 585-7560