16' Garage Door Headers

[brudgers]

Re: 16' Garage Door Headers

Rick A;Plain and simple, I have the experience, education and certifications to work as a commercial plans examiner and do a through plan review in among other disciples, structural. What you think is enough or not has no bearing.

What is that education, experience and certifications. Provide full itemize listing.

You have...

You have...

.... what? High School Diploma and hmm.... a number of years as a framer.... doesn't require you to know engineering. Pass some exams that says you can read some blueprints. (technical prints). It doesn't require knowing how to engineer and engineering science.

Hmm... pass some exams that says you understand the code book and how to read blueprints. Ok. Not enough. Doesn't require any knowledge of engineering sciences and the math.

To be able to review engineering calcs will need the requirement of the knowledge of engineering sciences. You think that high school education is enough?

Alright, how do you determine the maximum tensile force on the following cable.

"A cable is supported at points 100-ft. apart. The right support is at a level 5-ft. higher then the left support. The cable carries a concentrated load of 10 kips at mid-span with a final sag of 5-ft relative to the left support. " Report tensile force in units of kips.

Nobody help Kilitact.

You can't without knowing the physical properties of the cable.

 

[RickAstoria]

Re: 16' Garage Door Headers

Just because I am not licensed does not mean I am not professional.

You only have to look at my plans for maybe a few weeks. I may have to spend 9 months to design and spec things out. I design what is to be built. So, I am more qualified on the matters of building design then you are as it appears. You say nothing about your education other then pointing to the minimum. It doesn't say much of anything.

If you simply said,

I got ____________ degree in _____________ at ____________________ college/university.

I self-studied _______________ and studied these following books: (list)

I worked at ___________________ as ____________ for ________ months or years.

Just things that would answer the darn question. Now you got another question to answer, smartass.

You claim you are qualified to review calcs. Then it means you are qualified to answer that question.

 

[Heaven]

Re: 16' Garage Door Headers

If a person can not calculate the gravity loads on a header for a simple garage, they have less business reviewing plans than a homeowner does desiging the beam.

One of the points of this discussion is, even if we CAN (and many of us in fact can,) it is not part of our duties while representing our jurisdictions.

Accepting a appropriate stamped plan is code compliant, assuming we have made a reasonable effort to verify that the stamped DP is qualified in his/her line of work, and that they did or had close supervision over the work that they stamped, and the presumptive loads are correct for the application. That is a BO's due diligence.

There is no way any department in the country recalculates every piece of the engineering in every submitted plan. If you know engineering, and you know plans, that becomes obvious. Who checks the plan checker? The plan checker will also make errors. There will always be errors, omissions and conflicts in building plans.

 

[RickAstoria]

Re: 16' Garage Door Headers

You can't without knowing the physical properties of the cable.

Actually you can. What is asked is the tensile force on the following cable. Figure the cable is a standard steel wire rope cable. The question doesn't need to get to that stage of determining size of cable rope.

I'm focusing on a more theoretical engineering science level.

 

[Heaven]

Re: 16' Garage Door Headers

You can't without knowing the physical properties of the cable

*buzzzz*

Wrong

 

[brudgers]

Re: 16' Garage Door Headers

One of the points of this discussion is, even if we CAN (and many of us in fact can,) it is not part of our duties while representing our jurisdictions.Accepting a appropriate stamped plan is code compliant, assuming we have made a reasonable effort to verify that the stamped DF is qualified in his/her line of work, and that they did or had close supervision over the work that they stamped, and the presumptive loads are correct for the application. That is a BO's due diligence.

There is no way any department in the country recalculates every piece of the engineering in every submitted plan. If you know engineering, and you know plans, that becomes obvious. Who checks the plan checker? The plan checker will also make errors. There will always be errors, omissions and conflicts in building plans.

I was not suggesting that every calculation be checked.

I was merely saying:

1. members sized by designed professionals should be spot checked.

2. sealed engineering should not be assumed to be compliant.

These comments were specifically made in the context of a single member (header) on a small project (garage).

This led me to:

3. A person who cannot determine the adequacy of a simple garage door header has no business reviewing plans.

Based on your post, I'll add:

4. A person who won't reject an inadequately sized beam because it was sealed by an engineer has no buisness reviewing plans either.

 

[brudgers]

Re: 16' Garage Door Headers

Rick and Heaven,

A 100' cable hangs between two supports without an attached external load.

Is it in tension or compression?

Which and how much?

 

[brudgers]

Re: 16' Garage Door Headers

Rick and Heaven,

A thread is suspended between two supports 100' apart.

A five kip load is attached at the center.

How many threads do you have?

 

[RickAstoria]

Re: 16' Garage Door Headers

Rick after reading your comments here and on the old bb on this subject (reviewing calcs) I hope some day you will come work over on the dark side and realize your ideas on how plan reviews should be conducted are not practical for most building departments. Unless you are lucky enough to work for Kilitact

I know. My point with Kil is if he insists on checking every calc then he should have assistance or be adequately qualified to actually perform anything that maybe placed in his office. The minimum Plan Examiner qualification requirements are a far cry from the mimimal qualifications needed to check every calc.

I dropped a "bombshell" of a question for him. He needs to have the level an degree to design & calc the systems in which he wants to review the calcs for.

If he insist that every calc be checked then he better have an equivalent level of knowledge in engineering as those preparing the plans & calcs or have someone who is equally qualified assist. That is my point.

I asked about his qualification. He didn't give a real answer that shows the neccessary qualification to do so. I then gave him that lovely question regarding cable rope. I have no issue with light-weight systems like header beam over a garage door of a small garage. Kil opened himself up to a pandora's box.

 

[RickAstoria]

Re: 16' Garage Door Headers

Rick and Heaven,A 100' cable hangs between two supports without an attached external load.

Is it in tension or compression?

Which and how much?

In fundamental cable rope system, it is almost always in tension. So assume that when a load is applied, it is going to be in tension.

This is due to the flexible nature of cables. This systems are similar to suspension bridges.

This is a "Single Concentrated Load" system. Assume the cable as a "Free body". In real life, there is more factors often involved.

 

[north star]

Re: 16' Garage Door Headers

O.K. Paul, ya see what you started? D`OH !! Almost the same members too!

This has all the trimmings to resemble the "stairways-to-attics" thread, ...eeeeerrrr

rumble, ...eeeeeerrrr battle.

Just where is that packsaddle with the popcorn eating emoticon? :lol:

 

[RickAstoria]

Re: 16' Garage Door Headers

Rick and Heaven,A thread is suspended between two supports 100' apart.

A five kip load is attached at the center.

How many threads do you have?

The purpose of the equation is to determine the load. The number of wires in a strand, diameter of wire, number strands in the rope is not necessary for the actual question at this stage. That is determined AFTER you determine the load. You spec those out when you know what the load conditions are.

Don't worry about the number wires. Assume, you have sufficient wire diameter, number of wires in each strand and number of strands in the rope.

10 kips.

Determine the maximum tensile force on the following cable.

"A cable is supported at points 100-ft. apart. The right support is at a level 5-ft. higher then the left support. The cable carries a concentrated load of 10 kips at mid-span with a final sag of 5-ft relative to the left support. " Report tensile force in units of kips.

It would essentially sag 10 ft, relative to the right support.

 

[Uncle Bob]

Re: 16' Garage Door Headers

North Star,

Popcorn? If Pack read just read the first few pages of this thread; he probably ran out and bought a case of Old Grandad.

And, you should be banned for three days for cursing; "stairways-to-attics thread".

Rick,

I was negligent in not welcoming you to the forum when you first posted;

Welcome home.

Uncle Bob

 

[RickAstoria]

Re: 16' Garage Door Headers

North Star,Popcorn? If Pack read just read the first few pages of this thread; he probably ran out and bought a case of Old Grandad.

And, you should be banned for three days for cursing; "stairways-to-attics thread".

Rick,

I was negligent in not welcoming you to the forum when you first posted;

Welcome home.

Uncle Bob

LOL... Yeah... I still got it in me. :lol:

Anyway, blame Kil for opening his big fat mouth... :arrow: :cry:

Don't cry Kil.

 

[Heaven]

Re: 16' Garage Door Headers

My local snow loading exceeds the charts in the IRC anyway. Go figure. Somehow we manage to build things that don't kill anybody.

 

[High Desert]

Re: 16' Garage Door Headers

Actually the answer to Brudgers question on the thread with a 5 kip load would be you have two threads. The thread was not of sufficient strngth to support a 5 kip load so it broke.

 

[RickAstoria]

Re: 16' Garage Door Headers

Actually the answer to Brudgers question on the thread with a 5 kip load would be you have two threads. The thread was not of sufficient strngth to support a 5 kip load so it broke.

It is 10 kips in my original question and the question is what is the maximum tensile force on the cable.

 

[RickAstoria]

Re: 16' Garage Door Headers

Actually the answer to Brudgers question on the thread with a 5 kip load would be you have two threads. The thread was not of sufficient strngth to support a 5 kip load so it broke.

Oh. ok. I was interpreting things in a wholly different manner on context.

I was reading the whole matters differently. I wasn't reading it as a test question to me. I suppose it was a completely interpretation matters.

This can depend on the diameter of the thread / wire rope.

Brudgers, if you were asking what diameter steel rope is needed if you have a maximum tensile force of 5 kips then I would take a simple approach to this as I have a rope table. This makes life easier.

I would have a factor of safety of 2 at the least. 10 kips = 5 tons

In this case, I would use: 3/8" wire rope with Class C zinc coating which has a Minimum breaking strength of 5.9 tons.

This is based on some tables dating back to 1981. Basically, 30 year old charts.

Idealistically, I would go with 7/16" Class A Zinc coated steel structural wire rope.

 

[High Desert]

Re: 16' Garage Door Headers

rick, I just couldn't resist ribbing you a little.

 

[RickAstoria]

Re: 16' Garage Door Headers

It was all in how I interpret his question. As for Kil.... lol, has he figured out the answer yet?

HD: It is just a lovely & fun question for Kil.

 

[Uncle Bob]

Re: 16' Garage Door Headers

Well, if I go back to work as a Building Inspector, and pull up to a house for a framing inspection; where there is a cable across the garage door opening; I'm not even going to look at the garage door header.

I'm going to put a stop work order on the site until an Engineer sends me a signed, sealed inspection report on the cable.

Uncle Bob

 

[RickAstoria]

Re: 16' Garage Door Headers

Well, if I go back to work as a Building Inspector, and pull up to a house for a framing inspection; where there is a cable across the garage door opening; I'm not even going to look at the garage door header.I'm going to put a stop work order on the site until an Engineer sends me a signed, sealed inspection report on the cable.

Uncle Bob

Well... duh. These systems would be well-designed and all the calcs prepared but doubt it would be a header piece for a door.

It has specific application of use.

It was a point on regards to "reviewing calcs" and not just for headers.

 

[Uncle Bob]

Re: 16' Garage Door Headers

Rick,

"It was a point on regards to "reviewing calcs" and not just for headers."

I know, just couldn't resist kidding

There isn't one plans examiner out 1,000 that is qualified to do engineering calculations and there never will be; and, very few Municipalities that can afford to hire an Engineer to do the job. When most of us have to do plan reviews we use our experience, the codes, and engineered wood tables; and when something out of the ordinary shows up, we get the appropriate help we need from those who are more knowledgable.

Uncle Bob

 

[RickAstoria]

Re: 16' Garage Door Headers

Rick,"It was a point on regards to "reviewing calcs" and not just for headers."

I know, just couldn't resist kidding

There isn't one plans examiner out 1,000 that is qualified to do engineering calculations and there never will be; and, very few Municipalities that can afford to hire an Engineer to do the job. When most of us have to do plan reviews we use our experience, the codes, and engineered wood tables; and when something out of the ordinary shows up, we get the appropriate help we need from those who are more knowledgable.

Uncle Bob

Absolutely agree. This is EXACTLY the right way to do it. Don't perform work beyond your level of expertise. Hiring/contracting an engineer to do calc review for a specific project(s) that requires that extra help is the best way to do it. I wouldn't want a Plan Reviewer to go over their expertise. It is very bad. This is the point I was trying to point to Kilitact.

I hope he understands that and practice within his scope of expertise.