Truss to Interior Wall connection

[Yankee]

I have never seen Trusses that were not made by a Truss Manufacturer; and, the truss design drawings were provide by the Truss Manufacturer. Designing and manufacturing trusses is a complicated project. I can't imagine someone manufacturing trusses and providing the required information in Section R802.10.1; that doesn't have a qualified and experienced Design Professional.So, I'm puzzled by the question of whether the Design Professional needs to be Registered with the State.

If your asking if I would accept; truss design drawings by someone who is not in the "Specific" business of manufacturing trusses; the answer would be no. As the Building Official, I would require them to be designed by a Registered Design Professional in accordance with Section R106.1.

Uncle Bob

You do make some interesting points , wondering about your use of the term "registered design professional", in your mind is that only a liscensed engineer or architect, or does that include other non-liscensed designers (I know this is beat to death in another thread, but I am asking how YOU use the term?)

 

[mtlogcabin]

R802.10.2 Design.

Wood trusses shall be designed in accordance with accepted engineering practice. The design and manufacture of metal-plate-connected wood trusses shall comply with ANSI/TPI 1. The truss design drawings shall be prepared by a registered professional where required by the statutes of the jurisdiction in which the project is to be constructed in accordance with Section R106.1.

Yankee

The house may not require a arch or engineer by your state status but I will bet that the trusses do. What state are you in? Maybe sombody here could provide info about your specific state laws pertaining to liscense requirements for practicing engineering.

 

[FredK]

Ever talk to the engineer on a truss design? When I had an occasion to I found out that the truss company had retained his services and would send rough truss designs which were then re-checked by some engineer's assistant and then stamped by the engineer's assistant. Seems the engineer was paid by the number/size connection plates on the truss. IIRC it was a few cents per each plate.

 

[Mark K]

2009 IBC Section 202:

"Registered Design Professional. An individual who is registered or licensed to practice their respective design profession as defined by the statutory requirements of the professional registration laws of the state or jurisdiction in whidh the project is to be constructed."

non-licensed designers including the technician at the truss manufacture are not included.

 

[Yankee]

In my state someone under the direct supervision of a licensed engineer may do the work. But, , the points are well taken and certainly for a more than simple truss design I will look for the stamp.

 

[High Desert]

The engineer that stamps the truss drawings is probably not the one that designed the truss. Typically the engineer is retained to design the truss plates only, based on the densign of the truss company, which typically design their trusses on computer programs.

 

[GHRoberts]

I suspect that the software is vetted by an engineer. That is sufficient for me. I do not care who does the data input.

---

I have vetted the software I use. I have no independent way to determine if the numbers are accurate or not.

 

[Yankee]

I agree that engineer or not, the data inputted is the thing to check

 

[Mark K]

While an engineer will check the input he will also check the output to see if the output is consistent with the assumptions made. Thus the plan checker should have been trained as an engineer even if he is not licensed.

 

[incognito]

If the computer spit it out as OK the engineer stamping the truss details is not about to let his coffee get cold while "reviewing" the plans. He will check snow loading if applicable and wind speed zone and its a done deal.

 

[brudgers]

I agree that engineer or not, the data inputted is the thing to check

Yep. And that's often done by a CAD tech or a truss plant worker with a bad back.

 

[Mac]

NYState wants me to have stamped truss plans for each project that uses them. Applicant must provide them.

 

[Yankee]

While an engineer will check the input he will also check the output to see if the output is consistent with the assumptions made. Thus the plan checker should have been trained as an engineer even if he is not licensed.

In a perfect world maybe. But if the one man operation is actually a retired electrician, for instance, there isn't much chance of that. Maybe a good reason for that AHJ to require stamped plans.

 

[TJacobs]

If you're going to require truss drawings, require a seal.The software generates a truss based on the settings.

When the FBC 2001 was enacted, we required the truss drawings as part of plan review.

Wrong wind speed and wrong exposure were the obvious ones.

The fine print was where the devil lived.

My favorite was the note "Gable ends are not exposed to wind."

Though, a 5' hip jack designed for interior zone was a close second.

Needless to say, one reason for the brevity of my career in plan review is the number of truss shop drawings I rejected.

Charm had nothing to do with it.

Great post! The more you read them the more you find. I like when they defer some items to the building designer, who more often than not never sees them after they are designed. I also like when they specify sheathing that is not rated for the spacing of their framing.

 

[FredK]

When I work in the snow contry where loads ranged from 20 to 300 lbs we required truss sheets. I remember one time flipping thru the truss sheets and read the follow note: "This truss can not be built. Have an engineer design truss." About fell out of the chair laughing so hard. Even harder to explain that to the builder. Engineered fix was to sheet both sides of the truss.

Here the truss are on the job site and since most are standard engineered home plans the connection details are spelled out and easy to check.

 

[peach]

I've had truss shop drawings fail the "software" test.. and I reject them.. one element fails.. they all fail.

LOOK AT WHAT THE CONTRACTOR SUBMITS, don't just file it..

it's usually girders.. not always.. the shop drawings always show a few things (the design wind speed and whether it's an open, closed or partially open structure).

The truss design is only one part of the equation.. it's up to the building designer to determine if the trusses work.. whether or not that's a RDP, it's their responsibility.