What is considered a major defect when an inspector finds a horizontial crack on a foundation wall should be determind by a few things: First thing that has to be considered is the age of the home, the second is the size of the crack. Being a home inspector in NJ delivering the news to the buyer that there is a horzontial crack can be a tricky task. The standard of practice we follow states I have to note it in the report and advise the client to seek further evaluation from a structural engineer. I agree that a CYA statement is necessary, but I also want to be careful not use a scare tactic just to cover myself. I take the age of the home and the size of the crack and make a statement like the following: The house is 26yrs old the crack is no more then 1/8 of an inch. It does not appear structural. However for your peace of mind you might want to consider bringing in a engineer to verify my findings since horizontial cracks can lead to structural concerns. My first obligation is to my client. I will give them the facts and let them make the decision if purchasing the home still worth it.