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RE: Coordination with other trades

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"The precast was designed as a moment frame, and the
designer put quite a few hours in the design up front."

This is what makes subcontractors reluctant to spend their money to do preliminary design for us. I had similar experiences with precast contractors. These experiences just emphasizes the point that the design assumptions made on our drawings should be very clear so that we can put the responsibility where it truly lies when a change is made in those assumptions. 

I had a recent experience where the sucessful elevator contractor was in our office several times  during the design phase. He failed to tell us of a requirement for a 5-0 x 3-3 x 5-0 foundation block which extends into the elevator pit and gets doweled into it.  The elevator pit was already poured before he told us about this.  This is on a guaranteed price job to the Owner. 

Jim K.

-----Original Message-----
From: Jason Kilgore [mailto:jkilgore(--nospam--at)leok.com]
Sent: Friday, July 18, 2003 8:46 AM
To: seaint(--nospam--at)seaint.org
Subject: Re: Coordination with other trades


> A much better solution is to get the sub on board before documents go out.
> Then as a team you can design the most economical design.  Inform people
> that if they are not on board, you may have to do a redesign which will
cost
> everyone money and more importantly TIME!  Again, not always possible.
But
> if you inform your client about this before hand and they ignore you, you
> will have a good case for a change order.

This is normally an excellent idea, but here is a story about how this can
be abused:

I worked on a project with a precast concrete wall lateral system designed
by others surrounding a steel beam/joist system designed by me.  I say
"wall" only because it's what the architect called it.  It was really a thin
beam-column system (8"x6'-0" columns with 6" panels at floor and roof
levels.  The general and sub were supposedly selected up front, and I worked
closely with the precast designer to make sure the lateral loads were
transferred correctly from my diaphragm to his panels, then from his panels
to my foundation.  The precast was designed as a moment frame, and the
designer put quite a few hours in the design up front.

When sub bids were opened, however, the general selected a different low-bid
precast supplier.  This reeked beyond description, but I had no control over
it.

The contract documents specified that the contractor supply sealed
engineering calculations (Kansas) along with fabrication drawings.  At the
pre-construction meeting, I found out that first, the new fabricator did not
have an engineer registered in the state of Kansas and was hiring a local
firm to "review" and stamp the design and second, the precast was designed
as a cantilever column system instead of a moment frame.  I haven't reviewed
the Kansas regulations yet, but I'm pretty sure plan-stamping is illegal.
And the new lateral system significantly increased the loads on my
foundation.  But, since all I did was put the lateral loads on the drawings
and not specify the exact lateral system, I'm stuck with redesigning the
foundation and trying to get more money for it.

----
Jason W. Kilgore, PE, SE
Project Engineer
Leigh & O'Kane, L.L.C.
jkilgore(--nospam--at)leok.com
816-444-3144
816-444-9655 (FAX)



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