# catheral cielings ridge beam



## Rick18071 (Apr 23, 2013)

2009 IRC R802.3.1 says where ceiling joists or rafter ties are not provided the girder is designed in accordance with accepted engineering practice.

So where do I get this? Do I use the beam chart?


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## mark handler (Apr 23, 2013)

If you do not use ties, it is more than just sizing the beam, it also entails the connection details.

you need an design professional to design it.

Remember the purpose of the ties to resist the thrust that the rafters exert on the walls


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## Rick18071 (Apr 23, 2013)

catheral cielings ridge beam

Have a old permit that a previous inspector had approved the plans back in 2005 using 2003 IRC. Plans don't specify framing details. Already built with no inspection.  It's a enclosed breezeway. Beam is 12'long resting on existing house and garage walls. Breezeway is 12' x 20'


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## mark handler (Apr 23, 2013)

Rick18071 said:
			
		

> Have a old permit that a previous inspector had approved the plans back in 2005 using 2003 IRC. Plans don't specify framing details. Already built with no inspection.  It's a enclosed breezeway. Beam is 12'long resting on existing house and garage walls. Breezeway is 12' x 20'


...And...?


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## GBrackins (Apr 23, 2013)

and your involvement now is for what if it has been constructed?


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## Rider Rick (Apr 23, 2013)

GBrackins said:
			
		

> and your involvement now is for what if it has been constructed?


Final Occupancy.


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## mark handler (Apr 23, 2013)

Rider Rick said:
			
		

> Final Occupancy.


A previous inspector had approved the plans back in 2005, and Final Occupancy in 2013?

Can you see how it was constructed? If not how can you issue a Final Occupancy?

How many code changes since permits were pulled?

How do you keep a permit active that long?


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## Min&Max (Apr 24, 2013)

In my opinion you have to inspect based on what the code was when the permit was issued. So, what was used for the ridge?


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## Rider Rick (Apr 24, 2013)

Mark,

Coved prior to this inspection NOT APPROVED.


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## Rick18071 (Apr 24, 2013)

catheral cielings ridge beam

I am there to inspect. My job is to try to close 1000 open permits that the previous BCO let go. This permit has no inspections and no CO.


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## Rider Rick (Apr 24, 2013)

How can you approve something you can't see?

Open it up or NOT APPROVED that's how I do it, you can do it anyway you see fit.


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## GCtony (Apr 24, 2013)

Rick18071.  If that's your zip, closing 1000 permits is we'll.....going to be "interesting"  I built my first personal house up there in 87 and never had a single inspection.  If you had a question for the inspector, You had to stop by the hotel.  Never returned a phone call and the permit office was a desk in his garage.  How many years are you going back? 1000 is a big number considering the area.

Keep in mind that many of those people that pulled permits are less at fault than the town and townships. I hope you have what it takes to work with those folks.  I truely wish you the best.

On this particular one, knowing what I know about that area, how about asking the HO to explain how it was constructed or contact the contractor who did the work to explain how it was done.  The question of the day would be "is there any reason to believe it's unsafe?"  If you're asking "does it meet code?" well.......we'll reserve a room for you, one with padded walls.


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## Daddy-0- (Apr 24, 2013)

Your typical screen porch will end up with a ridge beam that will be a single or double lvl usually 11 7/8" all depending on span. You size it like any other beam as though it was a floor. You also need hangers where the rafters connect to the beam to be compliant.


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## tmurray (Apr 25, 2013)

GCtony said:
			
		

> Keep in mind that many of those people that pulled permits are less at fault than the town and townships. I hope you have what it takes to work with those folks.  I truely wish you the best.


I agree this is the fault of the municipalities, not the individuals. If you try to have them open and expose you could be opening the municipality to litigation. You should consult your solicitor. We had the same situation here when I started and we decided that we were going to let everything from the past go and from then on we would be carrying out mandatory inspections.


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## Rider Rick (Apr 25, 2013)

tmurray said:
			
		

> I agree this is the fault of the municipalities, not the individuals. If you try to have them open and expose you could be opening the municipality to litigation. You should consult your solicitor. We had the same situation here when I started and we decided that we were going to let everything from the past go and from then on we would be carrying out mandatory inspections.


The good oh boy way of doing business.


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## Darren Emery (Apr 25, 2013)

Daddy-0- said:
			
		

> Your typical screen porch will end up with a ridge beam that will be a single or double lvl usually 11 7/8" all depending on span. You size it like any other beam as though it was a floor. You also need hangers where the rafters connect to the beam to be compliant.


Daddy O - that's my take too, but having trouble finding a code section to require the hangers. Do you have a section to reference?


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## jar546 (Apr 25, 2013)

Rick18071 said:
			
		

> I am there to inspect. My job is to try to close 1000 open permits that the previous BCO let go. This permit has no inspections and no CO.


Wow,............all I can say is good luck with that.  Although something is better than nothing, the previous regime (especially if 3rd party)  should be having a heft E&O claim to assist the owners with compliance. On the other hand, this speaks pretty well for the contractors who just kept plugging along instead of contacting the township to tell them what was happening.  Gotta love Pennsyltucky.


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## Yankee (Apr 25, 2013)

Darren Emery said:
			
		

> Daddy O - that's my take too, but having trouble finding a code section to require the hangers. Do you have a section to reference?


I would like to see the section that requires hangers also.


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## mark handler (Apr 25, 2013)

Yankee said:
			
		

> I would like to see the section that requires hangers also.


If you do not provide the ties, the construction is no longer prescriptive and you need engineering

There is no way, to verify the connection will work without hangers or a designed gusset.


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## ICE (Apr 25, 2013)

deleted...


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## GCtony (Apr 25, 2013)

jar546 said:
			
		

> Wow,............all I can say is good luck with that.  Although something is better than nothing, the previous regime (especially if 3rd party)  should be having a heft E&O claim to assist the owners with compliance. On the other hand, this speaks pretty well for the contractors who just kept plugging along instead of contacting the township to tell them what was happening.  Gotta love Pennsyltucky.


A code compliance dept. up there is a pretty new thing, relativly speaking.  My opionion is 25 years ago, when that area didn't have a real dept. most of the contractors that were doing the work did the best they could with the best intentions of doing it right. The drawings that were used to build houses included a floor plan, a foundation plan and if you were lucky, a front and rear elevation.  No sections, details, specs, engineering. I THOUGHT I was one of the best carpenter/ construction workers and did everything right. Looking at it now, there probably isn't a house I framed that would meet modern code.  It wasn't that we ignored the messed up code office, we didn't know any better. It's just the way business was done.

The battle Rick may have is getting people to accept "it's no longer 1985, this is how we do things now and the past is the past"  The public in rural areas are going to fight the "new" system.  How does a code dept go about making things safer while showing the public that they are there to serve?  How do you tell someone that lived in a house for 5 or 10 years that they need to open up walls so it can be inspected?  It could be a great place to open up a law office. LOL


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## jar546 (Apr 25, 2013)

GCtony said:
			
		

> A code compliance dept. up there is a pretty new thing, relativly speaking.  My opionion is 25 years ago, when that area didn't have a real dept. most of the contractors that were doing the work did the best they could with the best intentions of doing it right. The drawings that were used to build houses included a floor plan, a foundation plan and if you were lucky, a front and rear elevation.  No sections, details, specs, engineering. I THOUGHT I was one of the best carpenter/ construction workers and did everything right. Looking at it now, there probably isn't a house I framed that would meet modern code.  It wasn't that we ignored the messed up code office, we didn't know any better. It's just the way business was done. The battle Rick may have is getting people to accept "it's no longer 1985, this is how we do things now and the past is the past"  The public in rural areas are going to fight the "new" system.  How does a code dept go about making things safer while showing the public that they are there to serve?  How do you tell someone that lived in a house for 5 or 10 years that they need to open up walls so it can be inspected?  It could be a great place to open up a law office. LOL


Pennsylvania has had an organized, statewide building code (PA-UCC) since April 9th 2004 so after 9 years, they should be getting it by now and this just proves that the oversight of the program is completely lacking.


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## tmurray (Apr 25, 2013)

jar546 said:
			
		

> Pennsylvania has had an organized, statewide building code (PA-UCC) since April 9th 2004 so after 9 years, they should be getting it by now and this just proves that the oversight of the program is completely lacking.


This isn't a local problem. We have jurisdictions here that will give you a permit to build your house without seeing a building permit. They also preform inspections, but do not check to see if deficiencies are fixed.


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## Rider Rick (Apr 25, 2013)

GCtony said:
			
		

> A code compliance dept. up there is a pretty new thing, relativly speaking.  My opionion is 25 years ago, when that area didn't have a real dept. most of the contractors that were doing the work did the best they could with the best intentions of doing it right. The drawings that were used to build houses included a floor plan, a foundation plan and if you were lucky, a front and rear elevation.  No sections, details, specs, engineering. I THOUGHT I was one of the best carpenter/ construction workers and did everything right. Looking at it now, there probably isn't a house I framed that would meet modern code.  It wasn't that we ignored the messed up code office, we didn't know any better. It's just the way business was done. The battle Rick may have is getting people to accept "it's no longer 1985, this is how we do things now and the past is the past"  The public in rural areas are going to fight the "new" system.  How does a code dept go about making things safer while showing the public that they are there to serve?  How do you tell someone that lived in a house for 5 or 10 years that they need to open up walls so it can be inspected?  It could be a great place to open up a law office. LOL


What happens when you approve something that fails and someone gets hurt God forbid.

I work in small towns where the same thing was going on and they chewed up inspectors right and left 6 of them in 2 years and then I came along and it was very hard for about the first year. But I stuck to my guns and treated everyone the same with respect and helped the contractors to learn and follow the code.

If they want to really to get a final you can work with them to find out what you need without that much damage.


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## mark handler (Apr 25, 2013)

Rider Rick said:
			
		

> What happens when you approve something that fails and someone gets hurt God forbid.


Sounds like the OP needs to verify the connection details, or add ties.....


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## GBrackins (Apr 25, 2013)

I guess I'm confused, could someone point me to the section of the 2009 IRC that requires metal connectors for a prescriptive rafter to ridge connection? Thanks!


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## mark handler (Apr 25, 2013)

GBrackins said:
			
		

> I guess I'm confused, could someone point me to the section of the 2009 IRC that requires metal connectors for a prescriptive rafter to ridge connection? Thanks!


It doesn't, but if you do not follow the prescriptive requirement of ties, you need to, per engineering standards show how you are preventing the "spread" of the RR and the reactions at the connection points


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## mark handler (Apr 25, 2013)

Basic engineering principle

A tie, structural tie, or strap, is a structural component designed to resist tension. It is the opposite of a strut or column, which is designed to resist compression. Ties may be made of any tension resisting material. In wood frame construction they are generally made of galvanized steel. Wood framing ties generally have holes allowing them to be fastened to the wood structure by nails or screws. The number and type of nails are specific to the tie and its use. The manufacturer generally specifies information as to the connection method for each of their products. Among the most common wood framing ties used is the hurricane tie or seismic tie used in the framing of wooden structures where wind uplift or seismic overturning is a concern.

Rafter ties are designed to tie together the bottoms of opposing rafters on a roof, to resist the outward thrust where the roof meets the house ceiling and walls. This helps keep walls from spreading due to the weight of the roof and anything on it, notably wet snow. In many or most homes, the ceiling joists also serve as the rafter ties. When the walls spread, the roof ridge will sag. A sagging ridge is one clue that the home may lack adequate rafter ties. Rafter ties form the bottom chord of a simple triangular roof truss. They resist the out-thrust of a triangle that's trying to flatten under the roof's own weight or snow load. They are placed in the bottom one-third of the roof height. Rafter ties are always required unless the roof has a structural (self-supporting) ridge, or is built using engineered trusses. A lack of rafter ties is a serious structural issue in a conventionally framed roof.

You can also use a buttress as in gothic architecture to resist the spread of roof/walls


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## GBrackins (Apr 25, 2013)

so then if you toe-nail plumb cut rafters to a ridge board with a collar ties ran under the ridge board attached to the sides of the rafters and you provide ceiling joists/rafter ties then you're good?


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## mark handler (Apr 25, 2013)

GBrackins said:
			
		

> so then if you toe-nail plumb cut rafters to a ridge board with a collar ties ran under the ridge board attached to the sides of the rafters and you provide ceiling joists/rafter ties then you're good?


Yes, based on the size and location of the ties and fasteners. Talk with your Structural engineer....


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## GBrackins (Apr 25, 2013)

glad to hear, thought when I started reading comments about requiring metal connectors something had changed ....


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## fatboy (Apr 25, 2013)

Sorry, I guess I am confused, y'all have fun with that.

But if you can calculate a ridge beam to carry the load, why does outward thrust on the bearing walls come into play? Would it not be neutral? Not trying to be argumentative, just thinking the properly sized ridge will support the loads without applying additional thrust on the exterior bearing wall.


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## GBrackins (Apr 26, 2013)

it shouldn't have any rafter trust .... unless I'm confused


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## mark handler (Apr 26, 2013)

Once again, you guys are flying off on tangents

to put it simple

you need ties or you need engineering...

That may include designing a ridge beam, that may include metal connectors but the code is clear

Ties or engineering design.


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## Daddy-0- (Apr 26, 2013)

Because you are designing it like a floor the same way you would if it was less than 3/12. The ceiling joists and collar ties resist thrust in both directions. If you take them away the roof must act like a floor and be self supported including a ridge beam that Is sized as a girder and rafters that are sized as joists. The "joists" must have a ledger strip or mechanical connection (hanger) because the entire roof assembly must be self suppoting like a floor.

The ridge beam must be supported by a post that carries the load to the foundation. You can use a ridge beam that sits under the ridge board to support if you wish but it looks kind of funny.


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## Daddy-0- (Apr 26, 2013)

We consider that method to be "acceptable engineering practice" here. Ridge beam with hangers.


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## Sifu (Apr 26, 2013)

R802.6-"The ends of each rafter or ceiling joist shall have not less than 1/12" bearing on wood or metal"  That being said I think thats a stretch for opposing rafters when proper rafter ties are installed.


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## Yankee (Apr 26, 2013)

I don't see where a metal connector is required to be used with a structural ridge as long as bearing is met. Although some might require a stamped engineered design for a structural ridge, I generally don't, and approve them using "standard engineering practice". Meaning, if the ridge beam is calculated properly for loading by the supplier, or sized properly as a built-up-beam by the contractor, I am comfortable approving the roof assembly with or without metal connectors.


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## Sifu (Apr 26, 2013)

WFCM does provide limited prescriptive ridge beam spans for given loads if you want to use them.  It is a nice tool to trot out when trying to illustrate the difference between a ridge board and ridge beam.  Otherwise I call it like this:  Structural ridge or rafter ties.  I do use the WFCM for available support spans for ridges.  I agree with Yankee, to a point.  I will sometimes accept a member report if I can verify (or decipher) the information on it.


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## mark handler (Apr 26, 2013)

Yankee said:
			
		

> I don't see where a metal connector is required to be used with a structural ridge as long as bearing is met. Although some might require a stamped engineered design for a structural ridge, I generally don't, and approve them using "standard engineering practice". Meaning, if the ridge beam is calculated properly for loading by the supplier, or sized properly as a built-up-beam by the contractor, I am comfortable approving the roof assembly with or without metal connectors.


How about the ceiling or collar tie question? not the metal connector question?


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## Jobsaver (Apr 26, 2013)

Where the 2006 IRC is applicable, I would direct attention to R802.3.1 including Table R802.5.1. referenced therein. This table gives prescriptive fastening requirements for the heel joint connections for ceiling joists installed as rafter ties and rafter ties installed above the top wall plate. The ties should extend laterally to the opposing rafter and fastened to the rafters according to this table.

To fatboy's position as noted in post#32, footnote c. of Table R802.5.1 establishes that heel joint connections are not required when the ridge is supported by a load bearing wall, header, or ridge beam.

It is true that if the ridge is supported in such a fashion that it cannot drop, no outward force will be exerted to the outside walls.


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## mark handler (Apr 26, 2013)

Jobsaver said:
			
		

> . The ties should extend laterally to the opposing rafter and fastened to the rafters according to this table.


And what happens when you omit the ties?


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## Sifu (Apr 29, 2013)

timbertoolbox has a rafter thrust calculator that gives the amount of thrust created by a rafter for a given condition.


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## Yankee (Apr 29, 2013)

mark handler said:
			
		

> And what happens when you omit the ties?


You may not omit the ties without then providing a structural ridge. Is that an answer to your question a few posts below? Or are you asking something else?


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## mark handler (Apr 29, 2013)

Yankee said:
			
		

> You may not omit the ties without then providing a structural ridge. Is that an answer to your question a few posts below? Or are you asking something else?


and how do you provide the structural ridge connection to Roof Joists without metal hangers?

Remember there is more than just gravity loads there are lateral loads, wind and seismic and there are temp loads in some areas like snow.


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## mark handler (Apr 29, 2013)

Without ties or metal hangers, identify how you will resist the uplift loads


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## Yankee (Apr 30, 2013)

Assuming metal connectors are not required from rafter to plate, why would they be required from rafter to ridge beam?


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## DRP (Apr 30, 2013)

3 pages in, I forget the question.

A nail is a metal connection.

Rafter to plate is tied with a hurricane strap for uplift unless nail calcs show they are sufficient, we simply use them out of habit. The rafters are hanging from a ridgebeam where they press against a ridgeboard. The top connection needs to be able to support that hanging load, half the rafter load, the other half of the individual rafter load is bearing on the wall. This could be toenails for short spans and low loads, it could be the infamous pressure block, it could be a $7 simpson skew hanger and most often I've used a long heavy framing angle with adequate capacity at ~$3/per.

 For uplift in EITHER roof system a collar tie (as opposed to a rafter tie) is used in the upper third connecting rafter to opposing rafter OR a metal strap from rafter to rafter is installed over the ridge, this ain't the hanger, it is another connection. In Marks drawing above when suction, or inflation from a blown out gable, pulls on the roof those upper collar ties or straps keep the roof from unzipping at the ridge.

In typical ridgeboard/ ceiling joist construction, the code heeljoint table specifies 16 commons and is lightly connected even then. The timbertoolbox calc came out of a class at VT. he connected sufficient to resist the rafter axial load, very conservative IMO, the tie tension is all that needs to be resisted if the rafter sits on a plate. If you tie as well as the calc that sucker could be connected out beyond the wall.

For the gothic buttress effect, intersecting wings will do the job.


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## mark handler (Apr 30, 2013)

yankee said:
			
		

> assuming metal connectors are not required from rafter to plate, why would they be required from rafter to ridge beam?


Who said they are not?


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## TJacobs (Apr 30, 2013)

In my neck of the woods, cathedral ceilings mean no ceiling joists/rafter ties or collar ties.  I require positive connections of the rafter to ridge beam, and the same rafter to top plate.


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## ICE (Apr 30, 2013)

Rick18071 said:
			
		

> Have a old permit that a previous inspector had approved the plans back in 2005 using 2003 IRC. Plans don't specify framing details. Already built with no inspection.  It's a enclosed breezeway. Beam is 12'long resting on existing house and garage walls. Breezeway is 12' x 20'


The project is not such a big deal that you couldn't approve it with confidence in your own ability to build it strong.

After all, you have seen many examples of what it takes span 12' from house to garage.

You have an approved plan.

It has stood for eight years.

Approve this one and sit back.

More will come to light.

The question then becomes, "What about that breezeway that you approved?"  "Why must I hire an engineer?"

Remember that engineers need to feed their families too.

It is never too late to start over.


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## mark handler (Apr 30, 2013)

DRP said:
			
		

> 3 pages in, I forget the question.


If you remove the prescriptive ties you need engineering to resist the forces resisted by the code required ties.

If you can structurally justify that in your area, without metal fasteners, all the best to you.


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## Yankee (Apr 30, 2013)

mark handler said:
			
		

> Who said they are not?


That sounds like you can't find the section that requires it. and you can't  : ). there are no prescriptive ties in a normal wind zone.See table 602.3(1) , items 4, 5 and 6


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## mark handler (Apr 30, 2013)

You are missing the point.there is a section of the code that requires ties.

the table of fasteners does not address that.

Nor does it address what is or is not required when the required ties are not provided.

.


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## tmurray (Apr 30, 2013)

mark handler said:
			
		

> You are missing the point.there is a section of the code that requires ties.the table of fasteners does not address that.
> 
> Nor does it address what is or is not required when the required ties are not provided.


This sounds like the argument I get into a lot with contractors. Prescriptive codes generally tell you how you need to do things and then provide exceptions. It typically won't give you a list of things you can't do.


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## mark handler (Apr 30, 2013)

tmurray said:
			
		

> ... a list of things you can't do.


You mean like what happens when you omit a required object and then use a table or section to justify what you don't have to do?

unlike  accepted structural principles


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## Yankee (Apr 30, 2013)

mark handler said:
			
		

> You are missing the point.there is a section of the code that requires ties.the table of fasteners does not address that.
> 
> Nor does it address what is or is not required when the required ties are not provided.
> 
> .


Sorry, didn't read your post clearly; the table I provided nailing requirements from rafters to ridge


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## mark handler (Apr 30, 2013)

Yankee said:
			
		

> ..... didn't read your post clearly......


Now you know why I get so frustrated


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## GBrackins (Apr 30, 2013)

mark, your nostril's are flaring ....


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## mark handler (Apr 30, 2013)

GBrackins said:
			
		

> mark, your nostril's are flaring ....


And that was after I calmed down.....


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## Yankee (Apr 30, 2013)

mark handler said:
			
		

> Now you know why I get so frustrated


How do you work with others, I wonder.


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## mark handler (Apr 30, 2013)

Yankee said:
			
		

> How do you work with others, I wonder.


Sweet as sugar....then you drink.....


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## GBrackins (May 1, 2013)

tisk, tisk, tisk, you know you have to watch your blood pressure ....


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## mark handler (May 1, 2013)

GBrackins said:
			
		

> tisk, tisk, tisk, you know you have to watch your blood pressure ....


have to watch my blood sugar....


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## GBrackins (May 1, 2013)

me2, such is life .....


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## Rick18071 (May 1, 2013)

I don't want to ask for engendering. It seems to me that by using the beam tables for a roof with ceiling attached for a ridge beam would be more than adequate. Someone told me there use to be a table for ridge beams in the code.


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## ICE (May 1, 2013)

Rick18071 said:
			
		

> I don't want to ask for engendering.


4x12 should do it.


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## GBrackins (May 1, 2013)

Rick18071 said:
			
		

> I don't want to ask for engendering. It seems to me that by using the beam tables for a roof with ceiling attached for a ridge beam would be more than adequate. Someone told me there use to be a table for ridge beams in the code.


Tables 3-29A-D of the 2001 Wood Frame Construction Manual provides ridge beam spans.


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## DRP (May 1, 2013)

At the risk of engendering the heat of ICE... I've seen palm trees in his pics, I haven't seen design loads or species and grade. Not saying he's wrong but I believe you just accepted structural sizing off the internet without all the variables known.

Older codebooks of mine didn't have ridgebeam tables... or even mention of ridgebeams. They did however have design values for multiple species and asked that I design according to accepted engineering practice. Which at that time was longhand using the table in the kitchen.  I'd ask the homeowners if they would mind a quick free safety check of the real culprits like decks, respect but note their response, close the books and start from today. We had no inspections for older homes here, what's the difference?


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## Sifu (May 1, 2013)

We are constantly pushing the rafter tie issue here.  In most cases we can tell them whats not compliant, give them the code approved options, give them the engineer option and at the end of the conversation they just go back to the same old argument; we never did that before, they don't make me do it over there, we ain't in no earthquake zone..etc, etc.  Sometimes those arguments come from inside the building!  I just keep plugging away.  WFCM helps me the most.  speaking of which they have a new 2012 edition but only in pdf so far (I want a printed version).  I am interested to see if it will have any new stuff on this subject.


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## GBrackins (May 1, 2013)

Sifu,

this link will give you the changes from the 2001 WFCM to the 2012 version.    http://www.awc.org/pdf/2012-WFCM-Changes-Web.pdf


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## ICE (May 1, 2013)

DRP said:
			
		

> At the risk of engendering the heat of ICE... I've seen palm trees in his pics, I haven't seen design loads or species and grade. Not saying he's wrong but I believe you just accepted structural sizing off the internet without all the variables known.


Oh I'm cool with whatever you come up with.

I suppose I leave out a lot of technical stuff because I don't know a lot of technical stuff.

I know that you do.

So let me narrow it down some for the guy that was asking.

#2 or better of the brown wood at Home Depot.  Brown is probably all that they have in 4x12.

If you're colorblind, go with a #1.

Oh wait a minute, yours is already built.  Ask for a receipt.

I don't know why the OP can't get a simple surprise like the correct beam size and connections from the guys that know.

For myself...well i figured that he asked enough times that he might be serious.


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## jwilly3879 (May 1, 2013)

8 years later and it is still standing. If everything else in the home looks good move on to the next one.


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## incognito (May 2, 2013)

And after 72 replies we have a winner!!! Thanks jwilly3879.


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## mark handler (May 2, 2013)

jwilly3879 said:
			
		

> 8 years later and it is still standing. If everything else in the home looks good move on to the next one.


Just because it is still standing does not mean it meets code

That can be the defense of the building owner in Bangladesh

But your honor, the building stood fine for three years before cracks begun to show

Why can't a few hundred die now and again

It stood fine for all this time just means that the loads have not yet been inposed on the structure

Give it time

If you don't understand the basic concepts you will never understand the application of them


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## tmurray (May 2, 2013)

ICE said:
			
		

> Oh I'm cool with whatever you come up with.  I suppose I leave out a lot of technical stuff because I don't know a lot of technical stuff.
> 
> I know that you do.
> 
> ...


Some of us were wondering about the legal liability. Others about what the potential for problems could be.

But I guess if someone asking for rope to hang himself, sometimes you just give him the rope...


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## ICE (May 2, 2013)

tmurray said:
			
		

> Some of us were wondering about the legal liability. Others about what the potential for problems could be.But I guess if someone asking for rope to hang himself, sometimes you just give him the rope...


Uh oh, I'm changing my answer to "Put a wall under it"


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## GBrackins (May 2, 2013)

with a beam under the wall?


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## ICE (May 2, 2013)

GBrackins said:
			
		

> with a beam under the wall?


This is a tough crowd.  Why would there be a need for a beam under a non-bearing wall?


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## Darren Emery (May 2, 2013)

jwilly3879 said:
			
		

> 8 years later and it is still standing. If everything else in the home looks good move on to the next one.


Perhaps we're getting close here - but Mark makes a number of valid points.  I happen to be responsible for tracking, and attempting to close our expired permits.  We drew a line in the sand in 2008, and created a system to flag expired permits on our database.  I now have 262 files that need inspected, re-inspected, or closed.  It is a constant, and apparently never ending battle.

For the case in question, way back from the original post - there are structural concerns.  No way would I issue a CO and move on.  Perhaps close the file, with notes indicating that inspections were not called for, but not a full CO.  A CO indicates my office is confident that the structure meets code.  I cannot say that.

On the other side of this coin - am I going to go back to this home, and tell the owner (who may not be the original owner at this point) "pull all the rock down, rip out the insulation, and call for inspections?"  Not going to do that either.

Somewhere in the middle  there is a balance of responsibility, accountability, and liability.  It is often very tough to find that balance.


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## GBrackins (May 2, 2013)

ICE said:
			
		

> This is a tough crowd.  Why would there be a need for a beam under a non-bearing wall?


if you put a wall under the ridge I take it that is to support the ridge? so wouldn't it be load bearing then and require support at the floor level ..... just messin' with ya


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## jwilly3879 (May 2, 2013)

Have to agree with Darren. There are a quite a few buildings in my area (very rural)that were either built without a permit or a permit was pulled and no inspections were ever called for. I will not issue a CO for these Buildings unless the owner can produce a letter from a Structural Engineer that the building meets the code in effect at the time of construction. File copy of letter to owner including wording that they should check with their insurance carrier because they probably don't have coverage, move the file to expired permit drawer and wait for the phone call. I have also had several cases where the property went up for sale, contracts were signed and the day before the closing the lawyer for the buyer requests a copy of the CO and the deal falls through. Then I'm the bad guy and the engineer is brought in, partial demo and repair ensue. It is so much simpler if it is done right the first time and real estate agents did their homework.


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## ICE (May 3, 2013)

Darren Emery said:
			
		

> On the other side of this coin - am I going to go back to this home, and tell the owner (who may not be the original owner at this point) "pull all the rock down, rip out the insulation, and call for inspections?"  Not going to do that either.


One nail is all it takes to


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## Sifu (May 6, 2013)

Thanks for link to the WFCM changes GB.  Based on the report it doesn't look like there is any new stuff on rafter ties but we'll see.


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## DRP (May 6, 2013)

I remember that ties used to be required every 4'. I'm curious as to the reasons behind the change, the plates, 2@2x6 now, can certainly carry the thrust to the next tied rafter, double the heeljoint nailing... I don't recall any prescription on the heeljoint connection.


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## mark handler (May 6, 2013)

DRP said:
			
		

> I remember that ties used to be required every 4'. I'm curious as to the reasons behind the change, the plates, 2@2x6 now, can certainly carry the thrust to the next tied rafter, double the heeljoint nailing... I don't recall any prescription on the heeljoint connection.


If you do not provide the ties, you cannot use the prescriptive requirements, you need to use engineering.

As long as you justify the "doubling of nailing", with engineering, your good, but *not a by-gosh by-golly guess, * it should work


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## fatboy (May 6, 2013)

If it is carrying the load at the beam, there is no need for ties for the thrust. I might be wrong, but isn't there a couple million roof/rafter/ceilings out there without them? I know I've framed a few that are still standing. But, I'm just a dumb ol' carpenter. I know there has to be proper connections.


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## DRP (May 7, 2013)

Yes Fatboy, if the rafters are hanging from the ridge and assuming the ridge does not sag, there is no outward thrust.

Having checked thrust against the heeljoint table and connection capacity, I am also curious where that engineering came from.


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## incognito (May 7, 2013)

I agree with fatboy. And I do not need or desire an engineer for every detail that may fall outside of the codes' prescriptive content.


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## mark handler (May 7, 2013)

Have you read the rafter tables?

The prescriptive sizes of rafters are based on ties and ceiling joists being used.

What do you do then ties and ceiling joists are not used?


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## DRP (May 7, 2013)

> The prescriptive sizes of rafters are based on ties and ceiling joists being used.


 Check the tables as simple beams.


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## fatboy (May 7, 2013)

"Check the tables as simple beams."

Yes.........


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## mark handler (May 7, 2013)

DRP said:
			
		

> Check the tables as simple beams.


You can "Check the tables as simple beams" or any other way The tabulated rafter spans tables assume that ceiling joists are located at the bottom of the attic space or that some other method of resisting the outward push of the rafters on the bearing walls, such as rafter ties, is provided at that location.

you are disregarding sections that require ties or ceiling jst. you cannot use prescriptive  and non prescriptive on the same assembly.

You need engineering to verify, or you may NOT be code compliant, by the way, there is nothing in the code or table about using the span tables as "simple beams" therefore, it is alternate construction

on the contrary rafters are sized based on repetitive use, just like a stud

Sometimes people have just enough education to be dangerous......


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## fatboy (May 7, 2013)

or too much............................


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## mark handler (May 7, 2013)

fatboy said:
			
		

> or too much............................


without understanding the basic concepts of engineering, anythig you do is a guess

Might comply might not.....


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## DRP (May 7, 2013)

Happily, we're not designing spaceships here. What we are talking about here is pretty basic stuff. I would prefer we broaden understanding so that those around us aren't just looking over their upturned thumb or pulling ridge sizes out of air without knowing the design load. Mark's approach leads to lower quality and a general erosion of the skills in the workforce, look around, real closely around. IMO bring everyone into the game as fully as possible. This thread demonstrates that those in charge of quality control need the free and honest exchange of this information, as do those involved in the actual work.



> by the way, there is nothing in the code or table about using the span tables as "simple beams" therefore, it is alternate constructionon the contrary rafters are sized based on repetitive use, just like a stud


 When one is checking a beam, (ceiling joists and rafters in the codebook are types of beams known as "uniformly loaded simply supported beams"), adjustment factors are used to account for repetitive members 24 or fewer inches apart, other adjustment factors account for duration of load, member size, etc.

If one were to omit or forget to use one or more of these adjustment factors the result would usually be a shorter allowable span, a more conservative design. The span tables use all of the allowable adjustments to the base design values. There are indeed situations where one could come up with an unconservative design, wet service docks the base design values.

With this in mind, post 85 and 88 are still points of discussion I would like to cover. Mark, I'd prefer for this to be covered by someone who can actually answer those questions if you'd leave that individual working room. I think we all understand and appreciate your position and I do not disagree with you entirely.


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## mark handler (May 7, 2013)




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## Glenn (May 8, 2013)

mark handler said:
			
		

> Have you read the rafter tables?The prescriptive sizes of rafters are based on ties and ceiling joists being used.
> 
> What do you do then ties and ceiling joists are not used?


Disagree.

R802.3.1

"...Where ceiling joists or rafter ties are not provided, the ridge formed by *these rafters* shall be supported by a *wall or girder designed *in accordance with accepted engineering practice."

There is nothing special required of the rafter..."these rafters"...as in...the same prescriptive rafters discussed earlier in the section detailing rafter ties.  Nothing special about the rafters when "ceiling joists or rafter ties are not provided".  The "wall or girder" however, must be designed using accepted engineering practice.  A plf load table from an engineered beam mfgr (LVL, LSL, Glu-lam) is not too hard to use.

Nothing fancy, unless you make it fancy.  We approve these prescriptively on small residential projects, otherwise wind drives engineering.


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## mark handler (May 8, 2013)

No. you agree go back and read the posts.

what I have been saying all along is "designed in accordance with accepted engineering practice."


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## fatboy (May 8, 2013)

"designed in accordance with accepted engineering practice."

And I for one, do not think that requires a stamp necessarily. If I can calculate a beam using section modulus and F/b, uniform loads, that is accepted engineering practice. It is a mathematical equation, not engineering.


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## Glenn (May 8, 2013)

mark handler said:
			
		

> No. you agree go back and read the posts. what I have been saying all along is "designed in accordance with accepted engineering practice."


I disagree that the rafters need special design.  The rafter spans are still valid even without the collar tie/rafter tie.  In fact, there is less stress on the rafters under a ridge beam situation.  With rafter ties, you can raise them up to one third the height of the rafters.  When they are raised, the thrust force is resisted within the span of the rafter.  This puts additional bending stress on the rafters, beyond just the live load supported.  This phenomenon does not occur when they are not installed and a ridge beam is in place.  Therefore I would argue the rafters are under less stress (potentially) than when constructed with rafter ties that could be raised.

Only the beam must be designed.

I also disagree with this statement:

"you cannot use prescriptive and non prescriptive on the same *assembly*."

R301.1.3 engineered design

"When a building of otherwise conventional construction contains structural *elements* exceeding the limits of section R301 or otherwise not conforming to this code, these *elements* shall be designed in accordance with accepted engineering practice.  The extent of such design need only demonstrate compliance of non conventional *elements* with other applicable provisions and shall be compatible with the performance of the conventional framed system.

I consider the beam to be an element of the roof assembly.  Performance is the goal...regardless of the mix of prescriptive, engineered or tested validation.


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## mark handler (May 8, 2013)

Glenn how do you justify, codewise, not putting in rafter or ceiling ties without engineering something?.oras some say "mathematics"? Of one or more elements?


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## Glenn (May 8, 2013)

mark handler said:
			
		

> Glenn how do you justify, codewise, not putting in rafter or ceiling ties without engineering something?.oras some say "mathematics"? Of one or more elements?


???

Please note:



			
				Glenn said:
			
		

> Only the beam must be designed.


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## mark handler (May 8, 2013)

Glenn said:
			
		

> ???Please note:


Ties required by code.

What happens is ties are not installed?


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## jwilly3879 (May 9, 2013)

The designed ridge beam basically creates 2 shed roofs, there is no outward force on the walls, just vertical. In my area the rafters usually sit on top of the ridge beam, not hung from it and they are strapped over the peak.


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## Rick18071 (May 9, 2013)

"...Where ceiling joists or rafter ties are not provided, the ridge formed by these rafters shall be supported by a wall or girder designed in accordance with accepted engineering practice."

So even if a simple 2x4 framed wall that is supporting the ridge needs to be engineered? But a wall supporting the top of a shed roof doesn't?


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## fatboy (May 9, 2013)

"girder designed in accordance with accepted engineering practice."

Again......... if you can do the math, it is accepted engineering practice, but not practicing engineering. Does not, will not need a stamp in my jurisdiction. It's a cathedral ceiling, not unlike the many tens of thousands, that have stood for centuries, all lacking an engineers approval......


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## mark handler (May 9, 2013)

fatboy said:
			
		

> tens of thousands, that have stood for centuries......


Tens of thousands of buildings stand today that would not meet the current building codes, are you saying we need to scrap the codes because these examples still stand?

and by the way, there are laws about practicing Engineering without a license...


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## fatboy (May 9, 2013)

I'm not practicing......

Have you noticed you are the lone ranger on this issue?

And I'm done.


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## Glenn (May 9, 2013)

It's called empirical evidence.  Mark...if everything had to be drawn up in an office by an engineer the world would never have been civilized.  I am out of this thread, as I don't feel you are completely reading the posts before you respond.  I feel you aren't taking this conversation seriously.  Enjoy your battle, but know that many are using the span tables provided by beam manufacturer's and the only "engineering" being done is figuring out PLF.  Sorry...not something worth defending your license over, but you are welcome to your opinion.


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## mark handler (May 9, 2013)

Glenn said:
			
		

> Sorry...not something worth defending your license over, but you are welcome to your opinion.


Are you implying my license is at risk over this?

I don't think you are reading the posts, you never did answer what you do to mitigate omitting the *code required ties*....


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## mark handler (May 9, 2013)

fatboy said:
			
		

> I'm not practicing......Have you noticed you are the lone ranger on this issue?
> 
> And I'm done.


I thought the pig enjoyed demud

I guess that's only when you're sure your right


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## mark handler (May 9, 2013)

Glenn said:
			
		

> It's called empirical evidence.  Mark...if everything had to be drawn up in an office by an engineer the world would never have been civilized.  I am out of this thread, as I don't feel you are completely reading the posts before you respond.  I feel you aren't taking this conversation seriously.  Enjoy your battle, but know that many are using the span tables provided by beam manufacturer's and the only "engineering" being done is figuring out PLF.  Sorry...not something worth defending your license over, but you are welcome to your opinion.


Empirical clause,  is that the I've been building it this way for forty years, ,clause?


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## Yankee (May 10, 2013)

mark handler said:
			
		

> Are you implying my license is at risk over this?I don't think you are reading the posts, you never did answer what you do to mitigate omitting the *code required ties*....


I still am reading it this way,_"__R802.3.1_

_"...Where ceiling joists or rafter ties are not provided, the ridge formed by __*these rafters shall be supported by a *__*wall or girder designed in accordance with accepted engineering practice."*_

So, , nuff said, we aren't making any headway and I shall agree to disagree.


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## mark handler (May 10, 2013)

I still am reading it this way,



			
				Yankee said:
			
		

> accepted engineering practice..


Not the non-existent Empirical clause


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## tmurray (May 13, 2013)

Yankee said:
			
		

> I still am reading it this way,_"__R802.3.1_
> 
> _"...Where ceiling joists or rafter ties are not provided, the ridge formed by __*these rafters shall be supported by a *__*wall or girder designed in accordance with accepted engineering practice."*_
> 
> So, , nuff said, we aren't making any headway and I shall agree to disagree.


So, are talking about picking an engineered product out of a table, or allowing a layperson to attempt engineering calculations?


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## jar546 (Aug 16, 2013)

Am reading this entire thread for the first time and see that it got a little testy but yet no resolution.  When I read some of the comments I think I am seeing where the intent of the post and the perception does not agree, even though in general, everyone seems to agree for the most part.

I would like to continue this great thread by posting what I am getting from this and this is also my opinion.  I will use numbers to make it easier to respond to and by the way, I am really loving the great information and opinions being shared.

1)  If you use a ridge board and not a properly sized ridge beam, you must have rafter ties in place to resist thrust.  I think we all agree on this.  Correct me if I am wrong.

2)  If you choose to use a ridge beam and support the weight of the roof between the ridge and vertical exterior walls, no rafter ties are needed because there is no outward thrust under normal conditions.

3)  There is the element of wind that creates outward pressure on the leeward side that creates an issue for designs with ridge beams and no rafter ties that needs to be addressed.

4)  If the design for the ridge is to support it prescriptively with a 2x wall that transfers the load to the foundation, that would not need to be engineered because the wall and any headers can be designed prescriptively.

Please let me know where we stand on my opinions and I will be happy to clarify any of them.


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## globe trekker (Aug 16, 2013)

I wonder if "Rick18071" ever got a satisfactory answer to his OP & Post # 3?

The OP seems to have turned in to another "Stairway to an Attic" topic.

We ARE trying to help answer questions on here aren't we?         ...and we wonder

why no one wants to become a Sawhorse, or to engage in to topical discussions.

Let's play nice folks!

.


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## GBrackins (Aug 16, 2013)

jar

#1 agree

#2 agree

#3 agree, see Table 3.6 & Table 3.6A of the Wood Frame Construction Manual for connection requirements

#4 agree, See Table 3.29 (A-D) for prescriptive ridge beams based upon ground snow load


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## Yankee (Aug 16, 2013)

tmurray said:
			
		

> So, are talking about picking an engineered product out of a table, or allowing a layperson to attempt engineering calculations?


I am talking about picking an engineered product out of a table after having determined the loading. I personally would not have my office document the use their(our) own calculations for the approval file as I think that would be a practice that might invite liability.


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## Rick18071 (Aug 17, 2013)

This post was very interresting. I agree with must of you except Mark on this. But i'm still using the girder tables in the IRC for the ridge beam. For a large roof I always see engnireed LVL's.

GBrackins, how does the IRC gider tables for support of a roof and cieling compare to the ridge beam in the Wood Frame Contruction Manual?


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## GBrackins (Aug 17, 2013)

to be honest I don't really know. I've used the WFCM since 96. We only went with the IRC here the past few years so I go with what I know. I typically use LVL's for ridge beams and they are sized according to the manufacturer's printed tables.


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## DRP (Aug 17, 2013)

You can use a table, correctly or incorrectly, you can ask the kid at the building supply to use a manufacturers software for an engineered product such as an LVL, which will yield the same results as the table. The manufacturer will give you the software to do the same thing if requested, the results would be the same as a table. You can do the math longhand or with a computer program that the manufacturers software is based on, which is how their software and the tables were derived... or you can pick some point in that chain where you are uncomfortable, rather arbitrary. For an engineered product the manufacturer supplies engineering support as part of the sale if requested so it's really a non issue there.

For solid sawn materials the AWC, as support for that industry, has come up well short of the mark. Their span tables and calcs are limited to single member beams such as joists and rafters where they could easily publish tables, give away software and provide engineering support for lumber products similar to what the engineered product manufacturers do. I've asked and their response has been that they don't have the funds available. That is actually bad logic, if they provided these services they would find greater use of their products. Quite often in order to satisfy an inspector it is cheaper to purchase an engineered product accompanied by a table or manufacturer's in house stamp than to engage a private engineer to show that a solid sawn product is adequate for the task at hand. This results in a less appropriate, more heavily processed material used where a perfectly adequate, cheaper and "greener" product might be the better choice.


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## GBrackins (Aug 17, 2013)

very well said Don! of course the AWC would be happy to sell you the WoodWorks software.


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