Do you know how to assess a foundation performance report?
My guess: No, you don’t.
In a Policy Advisory, the Texas Board of Professional Engineers (TBPE) stated that most of the complaints they receive concerning foundation performance evaluations are the result of poor communications. I take it that “poor communications” is a way of saying: engineers can’t write.
Part of the problem with writing foundation reports is that each report has a wide variety of audiences: the client who is usually not a technical person, the two real estate agents, possibly one or more repair contractors, other engineers, TBPE investigators – I could go on but you see the problem.
Now consider that simple words like “structure,” and “failure” mean different things to different people.
The previously cited Policy Advisory states:
Terms such as failure, distress, damage, etc. must be clearly defined.
When most people read or hear the word “failure” in reference to a structure, they immediately see a structure collapsing. When the structure is a slab-on-ground foundation, it cannot physically collapse for the simple reason that it is ground-supported. In my opinion, the term “failure” should never be used with reference to a ground-supported slab-on-ground foundation. It is virtually guaranteed to be misleading at best.
The document titled Guidelines for the Evaluation and Repair of Residential Foundations – Version 2, states:
The engineer should provide alternatives for the client’s consideration if performance is inadequate. Recommendations and alternatives should be commensurate with the nature and cause of the inadequacy and the seriousness of its consequences.
The typical Houston area single-family house that is ten or more years old will show irregularities that could be interpreted as being due to foundation distortion.
No or little discussion of risks
Here is what the Texas Section of the American Society of Civil Engineers says about the risk of continued diminished performance:
Risks of continued diminished performance are involved in all remedial measures. The engineer can, however, provide recommendations for remedial measures that reduce risks.
I rarely see any discussion of risk, even when foundation repair is recommended. That is amazing to me for the simple reason that underpinning a ground-supported structure can result in structural damage to the foundation and also to the house structure.
It is very easy for a Professional Engineer to recommend foundation repair. After all, he or she is not paying the bill. And there is a clear advantage to an engineer who recommends repair: no engineer ever got sued because he or she recommended repair.
Foundation repair rarely is cost-effective compared to improving foundation drainage, removing deciduous trees like oaks, installing root barriers between deciduous trees and the foundation, installing an automatic foundation watering system, etc.
In cases where there are no structural integrity or safety issues, making cosmetic repairs and correcting door problems are cost-effective and are all that usually needs to be done. In my experience, the most popular response to cosmetic issues and door issues is doing nothing. The second most popular option is to make cosmetic repairs to the cracks and adjustments to correct door issues.
Inspection versus investigation
The TBPE calls foundation performance evaluations by engineers investigations, not inspections. To better understand the distinction, consider ground fault protection. An inspection using the TREC SOP would involve using a testing device that can be purchased from any hardware store. What the device does not tell you is why there is no ground fault protection. Inspectors are not necessarily qualified to diagnose why a receptacle will not work. Diagnosis usually requires going beyond the TREC SOP.
Regarding foundation performance, the TREC SOP requires that inspectors render an opinion foundation performance opinion based on a list of visible performance indicators. A Professional Engineer would do something similar but would also make a judgment concerning the cause of performance indicators. In other words, he would diagnose the cause of any visible distress or damage.
A TREC inspector could arguably be found in violation of the Texas Engineering Practice Act if he or she implicitly diagnosed performance indicators as being due to foundation distortion or not due to foundation distortion.
Fairness to all parties?
Here is a statement from a Policy Advisory published by the Texas Board of Professional Engineers:
Engineers have an obligation to protect the property interests of the future homeowner, the builder, the lender, and all other parties involved.
Note that last phrase: All other parties involved.
That pretty much covers the waterfront. Given that the seller and buyer have different interests, how can an engineer be fair to both parties? So far as I know, the TBPE has never addressed this issue in any detail.
Here is that way I address this: I imagine that I own the house and must pay the cost any recommendations that I make. If the recommended repair is worth the expense and risk, then I recommend those actions that make sense to me and that I would make if I were the owner.
Elevation differences versus deflection
Elevation differences do not provide much reliable information. There is almost never any prior measurements to compare to and if measurements are available, they may be unreadable and useless – especially if made by a foundation repair salesperson.
What elevation measurements can do is to make an estimate of how much the foundation has tilted and how much it has bent or deflected. From a structural engineering perspective, what is important is deflection, not tilt, not floor slope, not levelness.