Welcome to the DoItYourself Forums!

To post questions, help other DIYers and reduce advertising (like the one on your left), join our DIY community. It's free!

Laminate beam needed?


CowDoc's Avatar
Member

Join Date: Oct 2006
Posts: 66
TN

12-30-06, 02:18 AM   #1  
Laminate beam needed?

I'm remodeling a one story, stick built house owned by myself and a friend. The section I'm dealing with is 24' X 24'. There are four equal sized rooms (i.e a square with a cross in the middle). The interior walls perpendicular to the ceilng joists are load bearing, from the ceiling joists only.

I calculate the live load to be 20 psf x 12 ft = 240 plf (attic storage), and the dead load to be 10 psf x 12 ft = 120 plf. Total load is therefore 360 plf. In truth, the attic contains blown insulation and has minimal access. There will be no storage. So, we are actually dealing with dead load only.

I would like to remove an 11' section of the wall to open up two of the 12 x12 rooms. I don't mind an exposed beam. The problem is that it has a low ceiling. The bottom of the wall top plate is only 7'1" high. Installing a 6" beam would lower the height to 6' 7" inches. I don't want to go lower than that and I don't want to go through the trouble of installing a flush header.

From span tables (and I ain't good at this), a 6x6 beam (Southern yellow pine) won't cut it... mainly due to deflection. But again, there really won't be any live load. As a compromise (between code and real life), I'm thinking about a small laminate beam.

I plan on contacting a local company that sells laminate beams, but I was hoping someone out there could provide a little "been there, done that advice". Am I on the right track? What is the best approach to this problem... other than putting a post in the middle of the room?

Thanks,
Barry

 
Sponsored Links
Jack the Contractor's Avatar
Member

Join Date: Dec 1999
Posts: 3,140
SD

12-30-06, 08:46 AM   #2  
Cowdoc: You seem to have done your math well. But, you do have some live load from you roof and being transfered through your bearing walls. Right now I am sitting here looking at a 10' opening in my own wall. Now mine is a 2 story, with a real upstairs and attic. My opening is 10 feet wide on the ground floor, with a 6' 9" height opening so I have alot of live load. It has been in place since 1962 with no deflection or sag. This is what I did. I used 3 2x6's, nailed them and bolted them. I countersunk the heads so the sides are smooth. Then I got a 1/4" thick of plate steel cut and attached it to the bottom. I did use triple studs at each end to set the beam on. It has worked very well, and only comes down 5 3/4". I do not think that they make 6" lam beams unless it is on a special order. Good Luck

 
Joe Carola's Avatar
Member

Join Date: Aug 2004
Posts: 117

12-30-06, 10:45 AM   #3  
Barry,

There's a company that I've used called "Better Header" that will make any size header you need whether it's a flitch plate or I-beam, interior or exterior. They will come any length you give them and the flitch plate is between 2-2x6's up to 2x12's and microlams.

If you click on the link and then click on "Beam Legends" you will see in the left column where they start out with 2-2x6's with a 1/4" flitch plate in between all the way up to 1" flitch plate in between.

I can't deal direct with them, I always use my lumberyard and they can find out if you can use 2-2x6's after you give them all you information.

I've also used on one job three years ago a 5-1/2" I-beam for a two story project with a 12' span. From what I remember, I think the top and bottom measured 5" also, which might be a problem for you if you have a 2x4 wall. You do have some options though if you don't want to put a flush beam in.

If not you have to go flush and you have many choices.


Good Luck.

http://betterheader.com/

 
mattb's Avatar
Member

Join Date: Dec 2006
Posts: 4

12-30-06, 06:08 PM   #4  
Your best best would probably be to either use a small wide flange (I beam), or make a flitch beam (already mentioned) by sandwiching a flat piece of steel (maybe .25" or so) between two (or more) lvls.

Like mentioned, I don't think they sell 6" lvls, but what you do is order a 12" lvl and you saw it down the middle. I completely opened up my house with steel beams and lvls. Several openings were done by sawing 16" lvls into 8" deep pieces and bolting them together (I needed 50' of the 16" for some areas so I ordered extra length to make the 8" pieces). I didn't need steel for these because I was sandwiching an existing 150 year old 4x4 (with some extra 2x4s as blocking) and the span is about 10'.

good luck.

 
CowDoc's Avatar
Member

Join Date: Oct 2006
Posts: 66
TN

12-30-06, 10:25 PM   #5  
Thanks to everyone for the tips and real life advice. It's been very helpful.

I located a manufacturer that sells 5 1/2" laminate beams. However, I don't know the particulars yet. I have been considering steel, but was trying to avoid it. Perhaps I can't. On the bright side, my friend is a welder at a large shop and gets a great rate on steel. Hmm, maybe some scrap railroad track. Lets see, 12' @ 90#/ft is about a half ton. Well... maybe not a good idea. I better stick with a flitch plate.

Jack, I'm a bit confused on how live load (presumably snow load) transfers to the ceiling joists. I thought the exterior walls carried all of the rafter load. This is stick built and not an engineered truss, but only the center of the ceiling joists are resting on this interior wall. I just don't see how the roof load could transfer. Still, better safe than sorry.

Thanks,
Barry

 
Joe Carola's Avatar
Member

Join Date: Aug 2004
Posts: 117

12-30-06, 10:32 PM   #6  
Matt,

Better Header does. Scroll down on the left and you'll see.

http://betterheader.com/beamlegends.asp

 
NHBuilder's Avatar
Member

Join Date: Jan 2007
Posts: 8

01-06-07, 08:28 AM   #7  
Hold up everyone...if I read his post correctly...there is a much simpler and cheaper solution to this problem. Let me first start off by saying i'm a licensed structural engineer, however, my advice is only as a contractor. If in fact your house is a single story with rafters and ceiling joists/collar ties, this is what I would do. In the attic (prior to removing the lower walls). Install a vertical 2x4 at mid-span of each ceiling joist running up to the peak. Make sure you either bolt these well with carriage bolts or make plywood gusset plates. The 2x4's will carry the dead load easily from the ceiling. THERE IS NO LOAD from the ROOF on those walls.

 
Jeff Matthews's Avatar
Member

Join Date: Sep 2004
Posts: 155

01-06-07, 03:16 PM   #8  
A variation of the previous idea is to sandwich 2 2x12's and lay them across the joists from the attic side. Lay the beam where 4" is along the joists and the 12" is vertical (for shear strength). There should be metal straps that you can use with nails to strap the joists to the beam from inside the attic. Both ends of the beam should sufficiently overlap a load bearing wall - say by 6" each side. This will work; it's easy, and no exposed beam on the interior.

2 2x12's will make the span and not sag. I wouldn't worry about the metal at all. Not for that short of a span.

 
T house's Avatar
Member

Join Date: Jan 2007
Posts: 6

01-06-07, 03:19 PM   #9  
I'm glad I found this forum, I have a mid 70s rambler & am looking to remove the center wall that supports the ceiling joist. Can I do as nh builder said & install 2x4's from ceiling to ridge on all ceiling joist & remove 25 ft of the wall that runs in the middle of the house?

I plan on consulting with a structural engineer anyway because I want to beam the basement as well but just curious if this is a standard method

Thanks

 
Jeff Matthews's Avatar
Member

Join Date: Sep 2004
Posts: 155

01-06-07, 03:36 PM   #10  
With no load (if the only thing it is carrying is sheetrock for the ceiling), you probably could. I would look for metal straps to attach the 2x4's to the ceiling rafters, though. They sell all kinds of straps at Lowe's and Home Depot. Ask for where the joist hangers are.

 
T house's Avatar
Member

Join Date: Jan 2007
Posts: 6

01-06-07, 03:38 PM   #11  
Also, since my roof is a gable with 2 staight sides & my house is a rambler does that mean none of the walls on the main level are load bearing?

 
T house's Avatar
Member

Join Date: Jan 2007
Posts: 6

01-06-07, 03:52 PM   #12  
The inner walls that is of course the outer walls are.

 
Jeff Matthews's Avatar
Member

Join Date: Sep 2004
Posts: 155

01-06-07, 03:54 PM   #13  
I had to look up what a rambler style is. I now know. Go in your attic. Are there any vertical are quasi-vertical members going from roof rafter down to joists? My guess is there are. That would change everything. In that case, the joists are carrying roof load.

 
T house's Avatar
Member

Join Date: Jan 2007
Posts: 6

01-06-07, 04:34 PM   #14  
Looking in the attic, from the middle wall there are 2x4's that extend out like a (y) every 4 ceiling joist. It goes from the load bearing wall (?) to the middle of the roof rafter.

Does this mean my only option is to intall a beam of some sort?

 
Jeff Matthews's Avatar
Member

Join Date: Sep 2004
Posts: 155

01-06-07, 05:19 PM   #15  
Y'ep! Use the same method I described above. But, to span 25', you'll need a heftier beam. Check into a product called LVL. The folks that sell LVL beams can usually spec what you need.

THen, think of the method you'll use to attach. I prefer a hidden beam. For my place, I framed temporary walls on both sides of the wall th be removed. I sandwiched a metal plate in between 2 2x10's - bolting them together.

I gut the joists above the wall I removed to make a channel the width of the beam. I put the beam up in between the cut joists. Both ends of the beam reast on vertical double 2x4's. I attached the joists to the beam with metal joist hangers.

 
T house's Avatar
Member

Join Date: Jan 2007
Posts: 6

01-06-07, 06:16 PM   #16  
Jeff,

Thanks for taking the time to explain this to me. I definatly like the idea of the hidden beam. Assuming I run a 25 ft beam should I expect a support on each end & 2 in the middle? Is a double 2x4 usually sufficient for a support?

 
Jeff Matthews's Avatar
Member

Join Date: Sep 2004
Posts: 155

01-06-07, 06:27 PM   #17  
A double 2x4 works for each end. Your best bet is to see if you can get the right dimension LVL to span the entire 25'. The key dimension is the exact (not nominal) measure of your 2 x ? joists. For example, a 2x10 joist is really 2 x 9 1/2, so in that case, I'd ask for a 9 1/2" LVL. You want it to flush with your joists.

Don't get discouraged by LVL. It is just a beam made of wood, but specially manufactured to carry a load better. A truss supplier will be able to tell you about it and might supply it or tell you where you can find it.

As far as putting posts in the middle. Pass on that. That's what I did at first, and I did not like it. So, I took my double 2 x 10 beam down and threw it away. I bought 2 new 2 x 10's and this time, a 1/4" x 9" steel plate. I sandwiched the plate by drilling holes in it big enough for several stout lag bolts. Then a attached it all together. It was strong enough to span the distance I needed - and no center pole!

 
Jeff Matthews's Avatar
Member

Join Date: Sep 2004
Posts: 155

01-06-07, 06:47 PM   #18  
Seeing as the inside of your attic will be above the beam, you might be able to do it the way I did. This assumes nothing above the joists in the attic, such as A/C or furnace, for example.

Steel plates, I believe, are available in lengths up to 30'. Let's say you ceiling joists are 2 x 6, for example. It would not matter if your beam is made of 2 x 12's if the protrusion at the top will not interfere with anything in the attic.

If you can find a 25' 2x12, all the better. If not, I feel sure you could use a 2 x 12 x 12 feet and another 2 x 12 x 13 feet and just have a single splice along the way. That steel standing vertically will not bow - or at least I can't see how it would. They build parking garages out of that stuff.

I would even bet you could go down to 2 x 10's or 2 x 8's using this method. I spanned 16 feet with 2 x 10's, and this was between floors in a 2-story house, so the load is way much more than just sheetrock. There's furniture, people, pets, all jumping around, etc.

The steel is very heavy. This is a 2 -person job. When you frame the temporary walls, make sure you have a 2x4 under each joist.

 
riverunner's Avatar
Member

Join Date: Jan 2007
Posts: 1

01-11-07, 08:49 PM   #19  
Just found this thread and could use some advice also.
In process of removing 20' section of load bearing wall. Want to put up hidden beam support in place of load bearing wall. House is a ranch style, stick framed.
I’m toying with placing beam on top of ceiling joist then strapping ceiling joist to bottom of new beam. This way I wouldn’t need to cut existing ceiling joist, which could jeopardize the triangle of the roof framing.

Is there an easer way to accomplish this? Can some of you give me some other suggestions as to how you would accomplish this? I would favor an over kill on the beam over the chance of a sag later down the road.

Tim

 
Wayne Mitchell's Avatar
Member

Join Date: Dec 2005
Posts: 3,188
CT

01-12-07, 06:26 AM   #20  
Did everyone miss the post by NHBuilder? It seems to me his recommendation would solve the problem with a minimum of expense and labor.
My house is stick built and I wanted to combine two small bedrooms to make a master br suite. I had the same problem as the OP, trying to figure out how to span 14' without an obtrusive beam extending down from an 8' ceiling.
My original plan was to install a versilam beam with the ceiling joists hanging from the beam with joist hangers.
When I applied for a permit my local building inspector suggested hanging the ceiling from the peak. I used 2X6's instead of 2X4's only because I had some laying around. It's been that way for 20+ years and there is no sag.

 
unccivil's Avatar
Member

Join Date: May 2006
Posts: 26

01-14-07, 08:09 PM   #21  
Exactly...you're just making a simple truss. You can do it with longer spans also by hanging 2x's at quarter spans (on the joists) as well...as long as the rafters have enough girth to support the mid-span load.

The only reason to replace a load-bearing wall with a beam is when it's supporting a floor above.

 
Search this Thread