Over the last 20 years I have spoken with hundreds of geotechnical and structural engineers about proper practices for a foundation investigation. I have asked the question if they would be comfortable rendering an opinion and a recommendation for foundation repair on the spot at a one-time visit. Almost without exception none would be comfortable doing it.
The interesting thing to note about Texas is the wide variety of practices. Because of the large volume of foundation problems, there are indeed hundreds if not thousands of repair contractors in Texas. I got to hear many stories of very interesting on the spot repair analysis. One was to simply put a golf ball on the floor and see where it rolls. Another was to take off your shoes and determine from your feet what the problems are.
If we follow the level B investigation as defined by the FPA or the Texas ASCE then a complete topographical analysis overlaid with a damage map followed by a deflection analysis is required. See my last blog (what should be included in a foundation investigation) for a complete discussion of that process. I’m not saying that that could not be done on the spot. However, I think it would be extremely difficult and time-consuming to do so on-site. I think our welcome would be worn out.
Instead what we commonly see is a salesman who simply gives his opinion about certain cracks or other signs of stress and what he thinks they mean. One popular video that runs on YouTube shows a non-engineer (but claims he is an EXPERT!) walking around giving his opinion about a normal settlement crack. Whatever that is.
I have been doing investigations for over 20 years, and during that time I have gone to a home and diagnosed it in my mind before analyzing the data carefully. Many times after analyzing the data carefully I have discovered my initial opinion was 100% wrong and backwards. I can easily see how misdiagnosis can happen.
In our process each of our detailed analyses is looked at, debated over, and evaluated by several people with the engineer taking ultimate responsibility for the final diagnosis and recommendations. Sometimes we have to return to the home to gather additional information. And on occasion, rarely, we will need to engage the services of a geotechnical engineer for additional information and soil testing.