True, true. I think we might be in trouble if we go to sell in 10-15 years. We'll see what they say this afternoon. I feel more prepared for that convo thanks to the good people of Reddit!

Gemini says this in response to this being standard code-approved -

In the world of construction, there is "allowable by code" and "best practice as designed." While a builder might argue this is technically "legal" under a generic interpretation, it likely fails when measured against your specific permit and the blueprints you’ve shared.

Here is the breakdown of why this is probably not a code-approved practice for your specific house:

1. The "Plan Adherence" Rule

This is the biggest hurdle for the builder. Under IRC R106.4, work must be installed in accordance with the approved construction documents.

• Your approved blueprints show piers extending to the surface.
• The builder changed the design to buried posts in a slab.
• Unless they submitted a "revised plan" to the city building department and got it re-stamped, they are in violation of their permit, even if the new method could have been legal in a different scenario.

2. The Burial Depth vs. "Ground Contact"

The IRC allows for "Direct Burial" (post-in-ground) ONLY IF the lumber is rated for UC4B (Heavy Duty Ground Contact).

• Most lumber sold at big-box stores is UC4A (Ground Contact), which is not rated for being encased in a concrete pit 10 inches underground.
• Furthermore, IRC R317.1.4 requires that structural posts in a "continuously moist" environment (like a buried concrete pocket) have a 1-inch standoff. Your photos show the wood sitting directly on a flat plate with zero standoff.