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RE: TPI - Plated roof truss discussion started by Tom Harris

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-----Original Message-----
From:	Richard Lewis [SMTP:rlewis(--nospam--at)]
Sent:	Tuesday, November 11, 1997 7:03 AM
To:	seaoc(--nospam--at)
Cc:	seaoc(--nospam--at); seaoc(--nospam--at)
Subject:	Re: TPI - Plated roof truss discussion started by Tom 

seaoc(--nospam--at),Internet writes:
The only thing I have been able to do is to require a 
meeting with the Truss Company included and to address my
concerns in front of the architect, GC and Truss company so that 
these issues are stated for the record. By doing this, I try to
force a resolution prior to placing the order for the trusses.

Dennis, this is a great way of handling it.   Do you have a 
typical meeting
agenda written which shows the specific topics you cover with 
all of these
people?  If so, could you share it with us?

Richard Lewis, P.E.
Missionary TECH Team

The service mission like-minded Christian organizations
may turn to for technical assistance and know-how.

[Dennis S. Wish PE]  Thanks Richard, no I don't have an agenda 
but simply "wing-it". I do walk into the meeting knowing where 
the weakness are in the design and laying them on the table for 
discussion. This generally leads to transference of 
responsibility to those individuals needed to resolve any design 
I also make sure that I review the design of each truss - 
something that I did not do in the past until I noticed that the 
heel measurements or intended bearing locations did not match my 
details. Since this time, I have become very picky about truss 
packages. I have a marked up set of calc's that are laid on the 
table and we dicuss my concerns.
There are some "standards" that I feel are important in the 
meeting and they include the following:
1. Discussion of the partnership to build. This is an important 
concept that draws each sub-contractor onto a common level with 
the engineer and architect. This, I hope, would reduce some of 
the animosity that historically develops between engineer and 
other trades. This is especially true during times such as these 
were we are trying to correct bad habits that were allowed to 
develop because of no prior intervention. I explain that we are 
entering this project for the purpose of constructing a building 
for a client in the most efficient manner and with the least 
penalty to the client for revisions due to conditions that 
should have been discovered up front. I also assure the 
contractor that I will be available to him without charge for 
clarification of any details. HOWEVER, if he wishes me to revise 
details for his benifit only, he will have to pay for it. I keep 
instilling the notion that the contractor must become intimately 
knowledgable with every detail on the plans and must never fail 
to call me with any question he may have that he does not 
2. Let them know what we expect when we will do Structural 
Observation. For example; verification of plywood or OSB panels, 
Common nail usage and less than 20% allowable overnailing in 
accordance with the provision by APA. (NOTE: I have all of the 
information that I will discuss already on the plans - I simply 
draw their attention to it personally).
3. I go over some obviouse conventional framing standards that 
are often abused in the field. These include, size of holes 
drilled in wood, allowable retrofit materials when the 
contractor forgets anchors, Placement and nailing of roof 
sheathing, blocking and the concept of shear transfers.
4. I take a few moments to explain the difference between wind 
and seismic to the framers in order to give them a basic 
understanding of load path developement. This can be done very 
simply using an open box example or fly-rod with a weighted 
washer example as to how the roof wants to slide away from the 
structure. I've used these examples on high-school students 
involved with building homes out here for the Boy and Girls Club 
of America. This really helps.
5. When the contractor can or can not substitiute materials.
6. Address the critical sections of the plans - for example, 
drags, connections that are critical, foundations used to resist 
moment (gradebeams etc.).
7. Leave the meeting with answers to your original questions or 
delegate responsibility to those that owe you the answers and be 
prepared to follow-up on it.

Finally, be prepared to make more than the structural 
observation visits that the client or contractor expects. Show 
up occasionally and note any discrepencies. Send out corrections 
and remind them of the pre-construction meeting.

I do one more thing that may or may not be valuable. I call the 
building inspector assigned to the project and I notifiy him of 
what I expect on the job. I ask that he keep his eyes open for 
certain discrepencies and ask him to contact me if he spots any. 
Remember, I live in a fairly small town (15,000) and a valley of 
less than 100,000 people. The building officials tend to work 
closer with the professional community here than in other 
cities. However, I found that the seismic retrofit community of 
professionals in Los Angeles were very aware of one another and 
worked very close - so the size of the community should have 
little or no bearing on the issue.

Dennis Wish PE