# Truss to Interior Wall connection



## Escape Goat (Jun 18, 2010)

What is the take on this ? I have not had Stamped drawings that allow or prohibit connection to interior walls. Actually never mentioned. However what I can find on most it is prohibited. This is not addressed in 2006 IRC other than RDP. Now I have one requiring no connection to interior walls floating ceiling if you will. How is everyone dealing with this? 90 percent always attach to whatever they can through the building and never has been mentioned. My thought is install according to RDP.

Thanks for any input.


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## High Desert (Jun 18, 2010)

Actually most truss companies only want their trusses nailed down at bearing points. There is a clip that you nail to the top of the wall and it turns up 90 degrees to the truss with a slot in it. This is so the walls are anchored but the truss is able to flex at the bottom chord. You do end up with nail pops, but that's how most truss companies want them attached.


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## Mark K (Jun 18, 2010)

In general trusses should not be supported by interior non-load bearing walls.  The truss design should indicate assumed locations of support.  These locations should be coordinated between the truss design and the RDP.

In other locations practice is to provide a small gap between the truss and the top plates of the wall.  There are standard hardware that helps brace the wall out of plane while allowing vertical movement.  I believe that the sheet rock on the ceiling needs to be detailed differently at these situations.  The RDP should address these issues.


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## FredK (Jun 18, 2010)

http://www.strongtie.com/products/connectors/STC-STCT-DTC_PT.asp#gallery


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## Uncle Bob (Jun 18, 2010)

Escape Goat,

Welcome to the forum.

First; Truss Design Drawings (2006 IRC, R802.10.1) are required; so, if they are not provided; inspection fails until they are. All the neccessary information is with the Truss Design Drawings and Truss Layout.

http://www.sbcindustry.com/images/publication_images/ttb%20partition%20separation.pdf

This should tell you all you need to know about non-load bearing wall connections; and, how the gypsum board is required to be installed; to prevent nail poping and/or separation of gypsum at ceilings.

You can also go here and get training on inspecting Truss installations;

http://www.sbcindustry.com/

and here for training;

http://www.sbcindustry.com/education.php

This training should be required for all inspectors who inspect Trusses.

Hope this helps,

Uncle Bob


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## Mark K (Jun 19, 2010)

While the SBCA web site can be informative they push an industry point of view.

One point that you should check is whether the truss design drawings were stamped and signed by a registered engineer.   The designer of the trusses is practicing engineering and thus the work should be signed by a registered engineer in the state where the project is located.  My understanding is that some truss manufacturers try to get by with using a technician to perform the design with no engineer providing oversight.


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## cboboggs (Jun 20, 2010)

Ditto High Desert. That is the way we are seeing them done here. But like the others have said, truss design drawings are required and the inspections should fail until they are present. One of the problems we are having is the builders are changing Truss companies and the as built trusses do not match what was approved for the master plan. These are handled the same way.


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## peach (Jun 20, 2010)

don't let the framer create a bearing point where it's not designed to be... that bottom chord is going to return to where it wants to be and will pull the wall along with it.  I've seen it..


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## Yankee (Jun 20, 2010)

Mark K said:
			
		

> While the SBCA web site can be informative they push an industry point of view.  One point that you should check is whether the truss design drawings were stamped and signed by a registered engineer.   The designer of the trusses is practicing engineering and thus the work should be signed by a registered engineer in the state where the project is located.  My understanding is that some truss manufacturers try to get by with using a technician to perform the design with no engineer providing oversight.


Somehow I lost my link to the Codes on-line (if anyone can re-supply?).

Wanted to check, are the truss drawings required to be stamped, or produced by "standard engineering practice"?


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## peach (Jun 20, 2010)

depends on the jurisdiction, Yankee, whether stamped plans are required.

You still can't allow invented bearing points.. which is exactly what happens when a truss is secured to a wall not meant to be a bearing wall..

There is no foundation connection.. where are the loads going to go?  (UP)...


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## Yankee (Jun 20, 2010)

No, I agree the truss should not bear on a wall unless it is called out as a bearing point (for the trusses sake mostly, I don't think there is significant gravity load transfered, as there most likely isn't a vertical web at the point of wall bearing). I was questioning the wording in the IRC for truss drawings (I'll look in the book tomorrow).


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## pete_t (Jun 20, 2010)

Yankee said:
			
		

> Somehow I lost my link to the Codes on-line (if anyone can re-supply?).Wanted to check, are the truss drawings required to be stamped, or produced by "standard engineering practice"?


http://publicecodes.citation.com/icod/index.htm


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## Mark K (Jun 21, 2010)

Why would stamped drawings and calculations not be required for trusses?

Section 107.1 of the 2009 IBC states "...The construction documents shall be prepared by a registered design professional where required by the statutes of the jurisdiction in which the project is to be constructed.  ..."


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## Yankee (Jun 21, 2010)

Mark K said:
			
		

> Why would stamped drawings and calculations not be required for trusses? Section 107.1 of the 2009 IBC states "...The construction documents shall be prepared by a registered design professional where required by the statutes of the jurisdiction in which the project is to be constructed. ..."


2009IRC Section802.10.2  Wood trusses shall be designed in accordance with accepted engineering practice blah blah blah, subject to Section 106.1 (which is similar to your quote above).

In my juristiction, most buildings built under IRC do not require a liscensed or registered design professional.

thank you pete_t for the link again!


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## Mac (Jun 21, 2010)

Research "truss uplift" for more info. With the bottom chord buried in insulation, trusses can react in unintended ways. Once we had...

Never mind, just look it up!


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## EPrice (Jun 21, 2010)

Yankee said:
			
		

> 2009IRC Section802.10.2  Wood trusses shall be designed in accordance with accepted engineering practice blah blah blah, subject to Section 106.1 (which is similar to your quote above). In my juristiction, most buildings built under IRC do not require a liscensed or registered design professional.


This would vary from state to state, depending on the engineer licensing laws.  In Utah and I assume many other states, if you're going to design something "in accordance with accepted engineering practice blah blah blah", you have to be a licensed engineer.  If you're an engineer and you engineer something, you have to stamp it.


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## Yankee (Jun 21, 2010)

EPrice said:
			
		

> This would vary from state to state, depending on the engineer licensing laws. In Utah and I assume many other states, if you're going to design something "in accordance with accepted engineering practice blah blah blah", you have to be a licensed engineer. If you're an engineer and you engineer something, you have to stamp it.


Is there adopted language that ties "accepted engineering practice" to"licensed engineer"? Just curious, because we don't have any language here, and I do see a difference.


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## texasbo (Jun 21, 2010)

Like others have said, look at your state law. Yes there is always language in the code to rely on in unusual situations, but some state laws exempt certain residential structures from compliance with the practice act, licensing law, or whatever your state calls it. We don't typically require signed and sealed truss drawings for SFR, nor does the state require that we do.


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## Mark K (Jun 21, 2010)

2009 IRC states

"R106.1 Submittal documents. Submittal documents consisting of construction documents, and other data shall be submitted in two or more sets with each application for a permit. The construction documents shall be prepared by a registered design professional where required by the statutes of the jurisdiction in which the project is to be constructed. Where special conditions exist, the building official is authorized to require additional construction documents to be prepared by a registered design professional. "

The need for stamped and signed truss designs is governed by Section R106.1 which envokes state licensing laws.  Section R802.10.2 addresses on what basis the documents will be evaluated.


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## Yankee (Jun 21, 2010)

I guess we'll have to agree to disagree on this one. If my state does not required stamped drawings for IRC, the code does not require stamped engineered drawings for trusses in general. Being the AHJ, of course, I may require them if I so choose based on an individual assessment of the project. But typically, I am satisfied with truss drawings produced " in accordance with accepted engineering practice".


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## Uncle Bob (Jun 21, 2010)

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


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## peach (Jun 21, 2010)

RDP or not.. truss engineer or not..

Truss designers design the trusses around the building design.. the building is not designed around the trusses.. don't create a bearing point where the building isn't designed to have one..

it's really not rocket science.


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## Min&Max (Jun 22, 2010)

Designing and manufacturing trusses is far from a complicated process. Actually went on a tour of a truss plant a while back. The designer(college drafting student) was sitting at the computer"designing" trusses. The computer program would not let him do anything that would not work structurally. Once the truss was designed the engineer took a break from Golf Digest prior to sending to the floor for production.


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## brudgers (Jun 22, 2010)

Min&Max said:
			
		

> Designing and manufacturing trusses is far from a complicated process. Actually went on a tour of a truss plant a while back. The designer(college drafting student) was sitting at the computer"designing" trusses. The computer program would not let him do anything that would not work structurally. Once the truss was designed the engineer took a break from Golf Digest prior to sending to the floor for production.


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.


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## Yankee (Jun 22, 2010)

Uncle Bob said:
			
		

> 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?)


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## mtlogcabin (Jun 22, 2010)

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.


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## FredK (Jun 22, 2010)

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.


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## Mark K (Jun 22, 2010)

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.


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## Yankee (Jun 22, 2010)

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.


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## High Desert (Jun 22, 2010)

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.


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## GHRoberts (Jun 22, 2010)

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.


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## Yankee (Jun 22, 2010)

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


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## Mark K (Jun 22, 2010)

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.


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## incognito (Jun 23, 2010)

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.


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## brudgers (Jun 23, 2010)

Yankee said:
			
		

> 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.


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## Mac (Jun 23, 2010)

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


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## Yankee (Jun 23, 2010)

Mark K said:
			
		

> 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.


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## TJacobs (Jun 25, 2010)

brudgers said:
			
		

> 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.
> 
> ...


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.


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## FredK (Jun 25, 2010)

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.


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## peach (Jun 27, 2010)

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.


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