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Re: Field Observations - Stupid things I've seen

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Greetings,

It seems that engineer/client relationships are the same everywhere in the
world. I designed an 10000 sq, ft. villa for a client. When we were done, he
decided that the villa was too big and therfore costly. He requested that we
reduce the area. When he was told that he would have to payva design
variation. He said what is the problem , The whole thing should not take you
more than 30 minutes, since we are in the computer age you just scale down
the plans using autocad by 60%, not realizing that a complete structural and
electro-mechanical redesign was necessary. When his request was rejected, he
said he would have the contractor do that.

-----Original Message-----
From: Seaintonln(--nospam--at)aol.com <Seaintonln(--nospam--at)aol.com>
To: seaint(--nospam--at)seaint.org <seaint(--nospam--at)seaint.org>
Date: Saturday, June 26, 1999 8:25 PM
Subject: Field Observations - Stupid things I've seen


>I liked this thread and thought that it would be interesting to accumulate
a
>thread of construction defects caused by both conventional construction and
>by contractors who don't read plans.
>Here is my contribution which occured this week.
>
>I received a call from my client - an architect, who designed a small 100
sq.
>ft. addition to a home for a special client of his. I engineered the
project
>and provided all the appropriate details for the project.
>The architect phoned to say that the contractor replaced a steel post with
a
>wood column and requsted me to approve the change since the steel column
was
>only intended to support a glass to glass connection acting as a mullion.
>There was no sufficient load to the column that a simple 4x4 wood post
would
>not handle. On top of this, the contractor put in a 6x6 wood post and
secured
>it to the foundation with a Simpson HD10A (I don't know why).
>I had to drop my wife off at the Palm Springs Airport and the job was
nearby
>so I decided to stop by and take a look. I ended up writting up an
>oberservation report and this is what was included:
>
>1. The new 6x6 post with an HD10A was approved - overkill, but acceptable.
>2. The building inspector failed to notice that the contractor moved the
>entry door over 12"' and reduced the only shear panel on that wall from 3'
>wide to 2' wide. The panel was 12 feet tall but was tied to the header at
the
>adjacent door. The wall above the headers for the entire length of wall was
>indicated to be sheathed in plywood - which was not done. So here I was
with
>a 12' tall x 2' wide shear panel with 8700 pounds of uplift (this is a
90mph
>wind zone) which was calculated at the net height of 9' taking the
sheathing
>into account.
>3. The framers placed all of the rafter blocking outside of the plane of
the
>wall - not above the top plate as I indicated on my details. Instead they
>installed a hurricane clip to each rafter and nailed it to the plate. I do
>not consider this to be an adequate shear transfer (certainly not in
>compliance with the code) and the deflection in the hurricane clip would
>certainly be a strong argument for a flexible diaprhagm.
>
>I wrote up the observation and called the head building official to discuss
>what his field inspector missed. I asked if the head building inspector
would
>verify that the work was completed per my report rather than have me drive
>the 35 miles back to the job. The head building inspector thanked me for
>bringing this to his attention (the city is known for being tough but he
was
>not aware that his field inspector missed this one) and told me that he
would
>personally take care of it.
>
>The toughest part was trying to make a retrofited tension anchor (holddown)
>work for the 8700 pounds when the best I could do with a Simpson SET
adhesive
>was about 6500 pounds. The capacity of the bond needs to be reduced almost
>50% for it's proximity to the edge of slab.  I finally had no choice but to
>take into consideration the existing HD10A which was only 12" away. I also
>drew upon some engineering judgment:
>
>There is an existing home on two sides of this addition. The actual new
>addition juts out only three feet from the existing structure. I
disregarded
>the existing structure because the architect did not provide me existing
>information or a full plan of the home. Therefore, I isolated and designed
>the addition as if it were free standing and separate from the main
residence
>- a good conservative approach. I know that the existing structure will
>absorb most of the shear if this wall proves to be inadequate in uplift,
and
>after seeing the home would conclude that the HDA's were probably
>overdesigned from the start (had I known). Therefore, I had the contractor
>install a new HD10A and embed it 11" into the fndt (18" deep).
>
>No matter how well the job is detailed or design, I have yet to meet a
>contractor that is willing or able to sit shotgun and protect a shearwall
>from the nimble fingers of a sub-contractor who wants to bring his
utilities
>up through the mudsill. The cutouts are very liberal and the GC rarely
>repairs the cuts properly.
>
>I'd like to read others who can provide stories of construction abuses.
>
>Regards,
>Dennis Wish PE
>
>