Odd you were not able to review the truss package prior to submittal for permit. I am required to write a letter of review and compliance of truss packages and calculation when submitting to some review agencies. Even so, I still put the earnest on the truss manufacturer to make things right, without doing the design for them, when issues arise during/after construction.
Not to pass the buck, but my shop drawing review stamp does say, "reviewed for general design conformance." What does your shop drawing review stamp say? Let's face it, for a residential all wood framed project that we've been awarded (which means we've already undercut our peer's "how much are we willing to lose on this one, bid") we as structural and/or civil/structural engineers, would blow 10% of our design and detailing budget on a fine tooth review of a truss calculation submittal even if you had the chance. I wouldn't dream of getting too involved with the design of the trusses unless that is your specialty, and further, you're familiar with the truss design software the truss engineer/designer is using. I check lengths, pitch, drag forces, top and bottom chord loads, and girder loads, but I am still not the designer or producer of the product. You're shop drawing review stamp is not a statement that the engineer who has stamped the truss package that he and/or a technician has set up has made no mistakes. You're relying on this engineering subcontractor's specialty, hold him to it, be critical of it, but do not design it unless this is within your area of expertise (yes it's within your engineering discipline, not the same thing).
Building department plan checker/reviewer's depth of review directly proportional to work load and/or third party out sourcing. Regardless, his/her responsibility can stop at making sure you've got a professional stamp on the required submittal documents. His/her shop drawing stamp might only say, "Has a stamp on everything". In other words, it's not his/her design specialty or responsibility either. Yes as the EOR, you are forever linked to the structural performance of the structure you are in responsible charge of. When dealing with third party, subcontracted,"by owner" professional engineering and product manuf. supplier companies, as you would review his original shop drawing for design conformance, I suggest you do the same for their repair detail, and hold them, per their contract with the homeowner not you, for the "performance" of their supplied product and this repair along with it.
That said, at length, my apologies!!!!!!............provided you take a peak at this 5 panel truss print out and check loading, span, member size/species, etc., there is no user error in the retrofitted truss design input data which another professional engineered regularly engaged in the design of trusses has stamped, the hanger "and don't forget lateral ties" are properly sized, the retrofitted truss bearing panel point connection is addressed, (they may sister a parallel web member below to resolve chord/web bending moments) and all looks reasonable, wouldn't this repair detail "appear" to be in general design conformance? If installed and the performance is not within acceptable tolerances, unfortunately, they may have to make another one.
(Meanwhile, while you may be a good engineer, you'll have to ask yourself how good of a businessman you are when it comes to receiving compensation for your time effort fixing the truss designer's error. Sorry I turn this topic into a money issue, but we must defend our right to compensation for our time and effort, especially when it is required due to errors, omissions, and changes of others. I hate seeing our profession get beat up, especially when it comes to owner builder residential projects. While I studied both Architect and Engineering in college and love home design, I rarely get involved with residential projects anymore, unless designed, managed, and permitted by a registered Architect. I don't even come close to getting most home projects I bid, because I am truly realistic about the time and effort involved. Franly, I don't know how some of my peers survive. There seem to be less and less home design and construction overseen by registered Architects these days and owner builder clients rely on the structural engineers to help manage and permit their projects bleeding us dry in the process while they laugh all the way to the bank) Second apologies for the rant,....up almost all night completing my last custom home design for awhile,...while I love what I do most days,...I do need to make some money. Strictly commercial for awhile again until the right residential project comes along.
