Liability / Re-use Fee for Factory-Built Housing 9

[SIPengineer]

As an outside consulting structural engineer for factory-built tiny home manufacturer who needs stamped drawings to get state approved permits in all 50 states, what kind of liability exposure fee is reasonable, considering the tens of thousands of units they will eventually be selling each year ?

Units will be designed for worst case loading in each state where possible, with location restrictions where loading is higher than the units can handle.

 

[SIPengineer]

Hey guys - Here's an update: I successfully negotiated a fee of $200 per house, in addition to my ongoing hourly fees.
Thank you all for your great advice, which emboldened me to achieve this !!!

 

[phamENG]

If they manage to sell those 160,000 preorders, you'll be sitting pretty. I wouldn't mind a cool $32M. Best of luck, and good job negotiating.

 

[SIPengineer]

Thanks phamEng. But I forgot to mentioned that it's capped at $250K per year.

 

[phamENG]

Not terrible. Here's to hoping they go slow.

Though, given the scale, of they discover a structural issue on one of these late in the game Merriam-Webster will have to print a special edition with your picture as an illustration for FUBAR.

But hey, that's business. No risk, no reward.

 

[Aesur]

@SIPengineer - the 200/house seems like a good number, although the yearly cap sucks, too bad you couldn't have a cap that raises each year as they ramp up; as phamENG said, hopefully they go slow! Out of curiosity, did you get them to cover your licensing in every state and do you have an exit clause (you know for when they start making 10k/year and you are getting screwed liability wise).

 

[SWComposites]

@SIPe - who is paying for your insurance?

 

[Prestressed Guy]

Let me tell you about a small project I needed to review in my second year out of college. It was a small aluminum greenhouse type building designed as a lean-to addition to your home. A restaurant that I was doing a remodel on was planning to use one as an indoor/outdoor seating area. The engineer used by the manufacturer did not have a stamp for our state so the firm I worked for agreed to review the drawings and calcs for a cover-letter.
The greenhouse structure was designed as a 3-hinge arch and the calcs had a full Risa model of each bent with lots of calculations. [oooh, shiny]
After looking through the design package for about 10-minutes I took it all to our senior principal and told him what I was doing and said I think there is a problem with this detail. after looking at it for a few minutes he said, "what's the problem?" to which I replied, "where is the flange?" In a about a second, he said "Oh shit!"

The splice detail for a tube section built up from face-to-face aluminum channels with a couple of splice plates that bolded to the web of each channel. The plates were about 50% thicker than the web which looked good.

The problem was that this connection will always be at the point of max moment and the splice was a shear connection with very limited moment capacity because there was an air-gap between the ends of the flange of the section.

I asked him what he wanted to do about it and was told, "you found it, Give the Engineer that designed it a call." Not a fun call as a green junior EIT to call a senior Structural Engineer who had signed off on the design of thousands of these structures which had been built all over the world that he had a fundamental problem with his design. I did the same scenario as I had with my principal only over the phone only his response was different. He sort of convulsively hyperventilated for about 5 seconds and then said, "I'll get back to you" and hung up.

After about an hour I had worked up a simple modification of his design that could be retrofitted the detail that would work for the loads on the one he had sent to us and said "This should work for ours.

I do not do designs for mass produced items. I have done Royalty designed where I get a percentage fee for each build similar to what phamENG described but only for limited quantities.

 

[phamENG]

I did the same scenario as I had with my principal only over the phone only his response was different. He sort of convulsively hyperventilated for about 5 seconds and then said, "I'll get back to you" and hung up.

Yikes. Every engineer's worst nightmare...(short of killing/maiming somebody, of course)

 

[XR250]

Did you actually check the plates for their moment resistance? Just because there is not a "flange" does not mean they don't work.