View Full Version : Main Beam Splitting

01-21-2009, 06:33 AM
My main beam in my basement is splitting down the middle on the underside. It's about six by eight.

What's the best way to reinforce it?

I was thinking maybe gluing and screwing a 2x10 to the underside(maybe making a sort of upside down T-beam).

Or some kind of metal bracing. Like the plates they have with teeth that you hammer into the wood.

I already have plenty of steel columns holding it up. It's not sagging or moving. Just splitting in the middle. The split goes up through most of the wood.

01-21-2009, 09:32 AM
If it is an older, solid piece of lumber then it is normal for it to check. I am surprised that it is still checking if it is very old.

The checks are allowed to penetrate up to half way through before they become an issue at bearing points. If it is only checked halfway through then you should be fine. If it is checked beyond the 1/2 way point then it needs to be either replaced or re-enforced.

The codes do not have prescriptive re-inforcement requirements so it will have to be designed if you plan on being compliant with structural code requirements. If it becomes a problem it is best to simply replace it. Our area has a lot of replacements.

01-21-2009, 11:44 AM
I don't think it's still moving. I have to check how deep it actually goes to see if it passed the halfway mark.

Any ideas on how to reinforce if necessary?

01-23-2009, 05:29 AM
Anybody ever do this before?

01-23-2009, 10:38 AM
Surely I haven't stumped everybody. If I did, do I get a prize from Terry?

01-23-2009, 02:04 PM
Probably lots of ways to do it right. Post a picture so we can see what you've got and you'll be flooded with suggestions.

01-23-2009, 02:09 PM
Yes: pictures, please. Is the split straight, on a diagonal? Is it in the middle of the beam, or does it reach one of the edges? Where are the posts, in relation to the split? etc, etc.

01-23-2009, 05:17 PM
A metal plate, on either side with bolts going through it. Trying to make an "I" beam would not work, because it would have to go over the support piers, not just between them.

01-24-2009, 03:22 PM
Darn. I was just there and forgot to take pics. The split is in the middle on the underside, goes down the length of the beam (most of it from what I can remember) and looked at it today and it looks to be a little deeper than halfway through. It's probably a quarter inche wide. The basement is 40 feet long. So is the beam (40 feet long) because it runs along the length of the basement. It's offset set a little less than the halfway point under the joists.

There are four steel columns in addition to the end walls supporting the beam.

I'll post pics as soon as can, but it may take a week. Any recommendations based on this info.

Can furthur describe the metal plate technique. I did figure some kind of metal plate would be best.

01-24-2009, 05:01 PM
Your best bet is to contact a structural engineer for a consult. I needed one during my remodel, and it didn't cost me an arm and a leg. That way, you'd get an adequate solution without guessing.

01-24-2009, 06:55 PM
It would probably be cheaper for me just to replace the beam with a new one. Do you think that this beam can fail suddenly in the condition that I described? I mean I am monitoring it, would I see more movement, sagging, or deeper splitting before it fails or do you think this thing can just collapse.

House is 20 feet wide, three stories. Joists are true 3x8's spaced 16" on center. The beam is 20 feet long (6"x8") with 4 intermediary steel colums(4 inch diameter) with foundation support on both ends. No twisting or rotting, just that damn splitting.

Is there something I can inject into the split? I mean at this point I'm just looking for ways to reinforce it, then when I have the money I'll replace it. Just looking to buy some time if I could.

Jim, I thought you were an engineer? You sure sound like one.

01-24-2009, 07:16 PM
You will need an engineer to determine what size beam to use as a replacement because you are off the charts with 3 stories even though the width is only 20'.

Assuming you are only in a 30 lb roof snow load area and if you were carrying only 2 floors plus the roof load, even with a triple 2x10 built up beam, you would need to support it every 7'3". That is for a 2 story building so you will need a bigger beam or closer support depending on which way you want to go.

You can alway call the local lumber yard and have them spec out an LVL. You can have it delivered in layers and assemble them inside the basement/crawlspace as long as you can get something that size in there.

Or just leave it alone because you have simple checking of the wood that is expected to happen with no sign of deflection.

01-24-2009, 07:38 PM
I just monitor it for now. It's been there for over 100 years, I think it will squeeze out another few more.

Jar, when you said "off the charts", was that a figure of speech or were you referring to an actual chart that I can look at?

01-25-2009, 08:20 AM
IBC and IRC charts. You have to buy the book to to get them.

02-14-2009, 10:33 AM
Here's my .02.

If you're really concerned. I'd have an I-beam placed on the underside of the wood beam and support the I-Beam with expansion jacks. If your really concerned then I would break through the basement floor and provide sturdy foundation for each of the jacks.

Though I bet you could get away with much the same thing if you were to use some very large beams placed over expansion jacks also with newly built foundations in the basement slab.

A picture would be nice.

Note: I'm not a structural engineer.