Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Building & Construction

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 01-11-2011, 09:51 PM   #16
Concrete & Masonry
 
Join Date: Nov 2008
Location: Wisconsin
Posts: 2,788
Rewards Points: 2,128
Default

26' Steel I Beam


Quote:
Originally Posted by jjohnson112 View Post
I'm planning to add on a 12' by 26' room addition to the end of my house going out over the driveway. I will be spanning the entire width of the driveway with a 26' steel beam. There can't be any supports in the middle of the beam because of the drive, and the beam can only be 12" tall for vehicle clearance. It is a gable end, so the beam will not be supporting much roof load. What size beam should I go with?
Sorry to be the bearer of bad news, but that won't work for you. Most 12" steel beams will have too much deflection under it's own weight in a span this long. You may have better odds at looking into a multi layer engineered wood beam instead, although it will probably be over 12" high as well.

jomama45 is offline   Reply With Quote
Old 01-11-2011, 10:25 PM   #17
Civil Engineer
 
Join Date: Mar 2009
Location: Boston
Posts: 4,273
Rewards Points: 2,124
Default

26' Steel I Beam


Design of a 26 foot steel I beam is a job best left to a professional. I say this because a beam this large is well beyond standard tables, hence requires individual sizing. In order to design such a beam, it is necessary to calculate the dead load and live load on the beam, which depends on house geometry and code mandated design loading conditions.

A steel beam this long must also be checked for buckling, which while not rocket science is not standard DIY computations.

There are four S shapes that meet the 12 inch criteria, and approximately 22 W shapes that could work. It is incorrect to state that Most 12" steel beams will have too much deflection under it's own weight in a span this long. In fact, there are NO S or W shapes that are approximately 12 inches deep that would have excessive deflection UNDER THEIR OWN WEIGHT. Some of them may not meet deflection or strength requirements given the combination of live and dead load, however that is why you hire an engineer to size the beam and design the connections.

In my experience, steel is likely to be less costly than wood for a 26 foot span with maximum depth of 12 inches. However, again that is why you hire an engineer, they will compare the options and select the best value shape.
Daniel Holzman is offline   Reply With Quote
Old 01-11-2011, 11:03 PM   #18
Residential Designer
 
AndyGump's Avatar
 
Join Date: Sep 2010
Location: Orange County CA.
Posts: 1,316
Rewards Points: 548
Send a message via Skype™ to AndyGump
Default

26' Steel I Beam


I think that too many assumptions are being made about this beam in question.

We don't even know if it is supposed to be the ridge beam, which if it is would be strange that it could only be 12" high? Why?

Or is it some exotic idea of the OP to hang it on the existing house wall and on the garage door header?

Who knows? I will wait for the OP to respond. I hope he answers some of these questions.

Andy.
AndyGump is offline   Reply With Quote
Old 01-12-2011, 03:56 PM   #19
Newbie
 
Join Date: Dec 2010
Location: Frankenmuth, MI, USA
Posts: 7
Rewards Points: 10
Default

26' Steel I Beam


Most likely, there is a driveway to the side of the house and they are building an addition over the driveway (ala porte-cochere). I saw them a lot in the middle-upscale neighborhoods in Texas.

The reason for the 12" limit is he is trying to match the level of the 2nd floor and that leaves 12" of room between a reasonable height for vehicles.

And yes, a 26' long beam that supports a room above it SHOULD have a professional look at it.
muthian is offline   Reply With Quote
Old 01-12-2011, 05:45 PM   #20
Newbie
 
Join Date: Jan 2011
Posts: 6
Rewards Points: 10
Default

26' Steel I Beam


Sorry I'm wasting everyone's time. The main reason I ask this question is the fact that I wanted to get a "round about" price from a local steel beam fabricator without paying $300 in engineer's fees just to find out that I want to go a different route because the size of the beam is so big it won't be worth the money. In order to get a "round about" price I need a "round about" steel beam size. I was assuming I could get by with either LVL beams for the outside wall beams or even 3-ply 2x12's, but would be having everything spec'd by an engineer before beginning the project. I will be over killing the two columns using either 18" or 24" diameter reinforced concrete columns on top of a footing on clay soil. Keep in mind the beam must be a W12 in order for vehicle clearance. I live in Terre Haute, Indiana...
jjohnson112 is offline   Reply With Quote
Old 01-12-2011, 05:49 PM   #21
Newbie
 
Join Date: Dec 2010
Location: Frankenmuth, MI, USA
Posts: 7
Rewards Points: 10
Default

26' Steel I Beam


No big deal. Vague description usually begets questions and responses. If you could provide more detail on exactly what the beam is supporting, etc then guesses could be made. Still a lot of variables that need to be dealt with before an accurate estimation can be made.
muthian is offline   Reply With Quote
Old 01-12-2011, 06:04 PM   #22
Newbie
 
Join Date: Jan 2011
Posts: 6
Rewards Points: 10
Default

26' Steel I Beam


The beam will be at the end of the addition. Assume you're pulling into a basement garage at the end of your house. It is a 6 and a 1/2 foot tall by 16 foot wide garage door with a 3-ply 2x12 header (we may have to add a flitch plate for strength). The wall extends 5 feet on each side of the door to make my 26' wide. I will be using wood beams extending out 12' from the end of the walls, resting on top of the basement walls and the concrete columns. The steel I-beam will be spanning from one column to the other overtop of the driveway. I will then use 2x10 floor joists running from the beam to the existing wall 16 OC. The gable end will be on top of the beam, so the side walls will be holding most of the roof load, while the beam will have half of the bedroom floor load and the existing wall will have the other half of the floor load. (I think thats right?)
jjohnson112 is offline   Reply With Quote
Old 01-12-2011, 06:05 PM   #23
the Musigician
 
DangerMouse's Avatar
 
Join Date: Jul 2008
Location: I'm right here!
Posts: 10,404
Rewards Points: 2,000
Default

26' Steel I Beam


Quote:
Originally Posted by jjohnson112 View Post
Sorry I'm wasting everyone's time. The main reason I ask this question is the fact that I wanted to get a "round about" price from a local steel beam fabricator without paying $300 in engineer's fees just to find out that I want to go a different route because the size of the beam is so big it won't be worth the money. In order to get a "round about" price I need a "round about" steel beam size. I was assuming I could get by with either LVL beams for the outside wall beams or even 3-ply 2x12's, but would be having everything spec'd by an engineer before beginning the project. I will be over killing the two columns using either 18" or 24" diameter reinforced concrete columns on top of a footing on clay soil. Keep in mind the beam must be a W12 in order for vehicle clearance. I live in Terre Haute, Indiana...
You're not wasting our time. The guys here love a good challenging thread.
Gives them all a chance to voice their opinions when not enough details are there to work with. It happens all the time, don't worry about it.
I recently finished a project similar to this, and MY engineer drew up two 2x12s on the outer, one indide, one outside bolted together, and double 11 7/8" LVLs heavily bolted together for the ridge. Then the trusses went up.
You might find that this may end up being the route you want to go. However, once you start and have the drawings done up, you'll find the inspectors a lot easier to get along with if you have the engineer's stamp on it. Well worth the $300 to have them run the numbers to keep it strong, and your family safe.

DM
__________________
[SIGPIC][/SIGPIC]Click here to see some of my original magic tricks and trick boxes!
DangerMouse is offline   Reply With Quote
Old 01-12-2011, 06:21 PM   #24
Newbie
 
Join Date: Jan 2011
Posts: 6
Rewards Points: 10
Default

26' Steel I Beam


Just so everyone knows, I'm not trying to find a shortcut to finding the beam size by going through a DIY forum. I'm simply wanting something to give me an estimate as to about the size so I can see if this project is even worthwhile. Engineers have to stamp anything that gets put up in our area, so in order to start the job, I will have to have plans and everything stamped.
jjohnson112 is offline   Reply With Quote
Old 01-12-2011, 06:34 PM   #25
Framing Contractor
 
Join Date: Apr 2006
Location: Caldwell, NJ
Posts: 1,758
Rewards Points: 1,000
Default

26' Steel I Beam


Quote:
Originally Posted by jjohnson112 View Post
Just so everyone knows, I'm not trying to find a shortcut to finding the beam size by going through a DIY forum. I'm simply wanting something to give me an estimate as to about the size so I can see if this project is even worthwhile
I understand that. The simple and safe answer for is that you cannot get it here. No one here is qualified to size such a beam. If someone did, would you trust that size from someone on the internet?

I've been framing a long time and what you have here is a big project and you are going to have to pay to get the answer. It's not just a little framing project with a beam that size.
__________________
Joe Carola
Joe Carola is offline   Reply With Quote
Old 01-12-2011, 06:41 PM   #26
Concrete & Masonry
 
Join Date: Nov 2008
Location: Wisconsin
Posts: 2,788
Rewards Points: 2,128
Default

26' Steel I Beam


Quote:
Originally Posted by Daniel Holzman View Post

There are four S shapes that meet the 12 inch criteria, and approximately 22 W shapes that could work. It is incorrect to state that Most 12" steel beams will have too much deflection under it's own weight in a span this long. In fact, there are NO S or W shapes that are approximately 12 inches deep that would have excessive deflection UNDER THEIR OWN WEIGHT. Some of them may not meet deflection or strength requirements given the combination of live and dead load, however that is why you hire an engineer to size the beam and design the connections.



In my experience, steel is likely to be less costly than wood for a 26 foot span with maximum depth of 12 inches. However, again that is why you hire an engineer, they will compare the options and select the best value shape.
I'll give you the fact that I may have "exaggerated" on the deflection comment. When loaded though, most 12" beams would have more deflection than I would be comfortable with, regardless of if they met typical deflection standards or not.

As for the engineer selling value, I think that you may be the only professional here that thinks that. Engineer's typically do whatever's easier for themselves and have little regard to saving either the contractor or end consumer money. Maybe your own approach is different, but my experiences would say that you're in the minority if that's the case.


Steel would be cheaper than wood in this scenario?? Maybe it appears that way to you, but in reality, if you figure in the fact that most any lumberyard will do the engineering, or at least get the engineering from the manufacturer, included in the cost of the wood beam, wood almost always comes out cheaper. I know you don't like to hear this, because it takes business away from folks like you, but it is oftentimes the most efficient approach financially.
jomama45 is offline   Reply With Quote
Old 01-12-2011, 06:46 PM   #27
Concrete & Masonry
 
Join Date: Nov 2008
Location: Wisconsin
Posts: 2,788
Rewards Points: 2,128
Default

26' Steel I Beam


Quote:
Originally Posted by jjohnson112 View Post
The beam will be at the end of the addition. Assume you're pulling into a basement garage at the end of your house. It is a 6 and a 1/2 foot tall by 16 foot wide garage door with a 3-ply 2x12 header (we may have to add a flitch plate for strength). The wall extends 5 feet on each side of the door to make my 26' wide. I will be using wood beams extending out 12' from the end of the walls, resting on top of the basement walls and the concrete columns. The steel I-beam will be spanning from one column to the other overtop of the driveway. I will then use 2x10 floor joists running from the beam to the existing wall 16 OC. The gable end will be on top of the beam, so the side walls will be holding most of the roof load, while the beam will have half of the bedroom floor load and the existing wall will have the other half of the floor load. (I think thats right?)
You may want to consider going to a lumber yard to have them price out the whole package for you. As I stated above, they will generally spec the beam for you as part of the cost of the beam. Most of the time, they can get a stamped drawing with the calcs as well, if you're required to present the to your building department.

One other thing to consider in a wood beam is that it is fairly simple & routine to hanger the floor joists off of the beam, giving you much more clearance underneath. For example, if the wood beam was spec'ed out to be X layers of approx. 16" high LVL, you'd only have 7" of the beam BELOW the bottom of floor joists.
jomama45 is offline   Reply With Quote
Old 01-12-2011, 07:19 PM   #28
Member
 
Join Date: Apr 2007
Location: Electric City wa
Posts: 272
Rewards Points: 250
Default

26' Steel I Beam


Quote:
Originally Posted by jjohnson112 View Post
The beam will be at the end of the addition. Assume you're pulling into a basement garage at the end of your house. It is a 6 and a 1/2 foot tall by 16 foot wide garage door with a 3-ply 2x12 header (we may have to add a flitch plate for strength). The wall extends 5 feet on each side of the door to make my 26' wide. I will be using wood beams extending out 12' from the end of the walls, resting on top of the basement walls and the concrete columns. The steel I-beam will be spanning from one column to the other overtop of the driveway. I will then use 2x10 floor joists running from the beam to the existing wall 16 OC. The gable end will be on top of the beam, so the side walls will be holding most of the roof load, while the beam will have half of the bedroom floor load and the existing wall will have the other half of the floor load. (I think thats right?)

OK am I missing something here ( I usually am) but if you are going to have a 5 foot wall on each side of the 16' door why do you need a 26' beam and not a 16' beam?
warnerww is offline   Reply With Quote
Old 01-12-2011, 07:31 PM   #29
Member
 
joed's Avatar
 
Join Date: Mar 2005
Location: Welland, Ontario
Posts: 8,094
Rewards Points: 2,982
Blog Entries: 4
Default

26' Steel I Beam


Go and ask the beam supplier. He probably has good idea of what you need.
__________________
Do not PM with questions that can be asked in a forum. I will not respond.
joed is offline   Reply With Quote
Old 01-12-2011, 07:52 PM   #30
Civil Engineer
 
Join Date: Mar 2009
Location: Boston
Posts: 4,273
Rewards Points: 2,124
Default

26' Steel I Beam


Yes I am a professional engineer, but I certainly do not think that is a negative. I always try to find the best solution to a client's problem, that is what engineers do.

Now as to this particular beam. I ran a few calculations just for fun, and it is clear that the 12 inch deep limitation, if it is actually controlling, would require a wide and expensive Glulam, based on 40psf load. Obviously I don't know the exact load on your structure, and this is absolutely not a design, but I checked a few 12 inch deep steel beams and they appear to work adequately from a deflection and strength standpoint.

And steel is relatively inexpensive. I recently installed a 12 lb/foot steel beam, and it cost about $300 for 20 feet, which works out to be around $1.50 per lb, cut and drilled. A larger beam in the 26 foot range would be less costly per pound, depends on the availability of steel in your area. At $1 lb, you would end up paying perhaps $600 for the beam. If you can get a working Glulam for less, go for it, I don't own any steel stock. Simply saying that based on some preliminary calcs, and lots of personal experience, I expect the steel beam to be considerably less costly than the equivalent Glulam due to the span. But again, you are going to have to hire an engineer to design it, and they can tell you for sure which size you need, and which option is more cost effective.

Daniel Holzman is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Question about steel I BEAM in basement djohns10 Building & Construction 7 06-23-2012 04:55 PM
How to repair main support beam Jerry48ece Building & Construction 0 01-08-2011 09:38 PM
Main Beam De-Laminating Bird Doo Head Building & Construction 6 12-09-2010 01:08 PM
Steel beam for deck billybarty Building & Construction 2 08-18-2010 01:27 PM
steel beam length otto man Building & Construction 4 07-27-2008 09:11 AM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.