DIY Home Improvement, Remodeling & Repair Forum

DIY Home Improvement, Remodeling & Repair Forum (
-   Framing and Foundation (
-   -   Main Beam Issues (

dw8 11-16-2011 11:18 AM

Main Beam Issues
Read with interest comments by all in johnbaum "Basement Main Beam Replacement".

I've got a slightly different situation.
The main beam is a sandwiched beam (two 2 X 13's) that runs the length of the home (about 50 feet). Each side of the main beam made up of two beams (approx 25 feet in length). They are bolted together as required. There are five concrete piers (16 x 16 block) supporting this main beam. The floor area is dirt as it is a crawl space.

The south side beam splice (joint) rests on a foundation support. However the north side beam splice (joint) does NOT rest on any support.

The main beam is starting to split on the bottom by the north side main beam splice (joint). To make matter worse, it appears the beams had a large crown when installed such that the low point exists where the north side splice (joint) exists.

I initially thought to put a steel beam or engineered beam between the footings
where the north side split (sag) occurs. However, to do this would require the floor to be raised and I believe this would impact the roof trusses sitting on the top plate of the interior walls That is as the floor is raised, the roof trusses (2x4's on bottom of truss) would be lifted and may crack or the truss splice (which rests approx over the main floor beam location) may give way.

My second thought was to put a 6 inch channel under where the splitting is occurring
(channel would extend well past the split area) and install two jacks. However, where I need to place the jacks, there are water lines buried underneath the earthen floor.

Suggestions Requested
Any suggestions would be appreciated -- other than hire an engineer -- which I believe I believe will result in the response of "tear down the interior walls and jack up the floor"

joecaption 11-16-2011 12:38 PM

One reason it's failing is there should have been at least 3, 2Xs not just the two you have now, to give you a wider bearing surface.
To get another one in it only needs to be lifted about 1/8 to 1/4" and should not hurt anything if the jacks are placed right and at least 3 are used on each side of the beam and the beams long enough to spread the load.
I highly doubt any engineers going to tell you to tare it down, but they will tell you the right way to fix it so it does not need to be done again.

nealtw 11-16-2011 05:48 PM

Your just putting back where it was, don't worry about the trusses.

dw8 11-16-2011 06:55 PM

nealtw - thanks for responding.



Your just putting back where it was, don't worry about the trusses.
It has not fallen -- appears to be original construction. Door frames square at top and sheet rock has no issues or cracks -- just my concern re. main beam and the above described splitting.


Do have another couple questions as need to put a couple of headers as swapping the toilet and shower. Floor joists are 3x9 (real not nominal) on 16 inch centers. Headers will be between joists so no headers over approx. 16 inches. With the headers installed, one tail joist will be about 12 feet the other about 4 foot.
FWIW not used to dealing with such wide joists.

1) Would I be better to use hangers to hold up the header against the joists and also use hangers for the tail joists -- or --
2) Use some 1/4 inch lag bolts (say two) that are offset -- not -- vertically aligned -- or
3) Try and pre-drill (since old wood) and nail?



nealtw 11-16-2011 07:31 PM

If nothing much has moved, just bolt on another say 2x12 over the joint from post to post.
I think you are talking about cutting floor joists to allow for plumbing. If we had 2x10s we would double the full length ones on each side and hang a double between them and hang the cut one from that. As you have 9x3s they should be strong enough depending on length.

dw8 11-17-2011 07:24 AM

Per "Strucalc" I supposedly have 50% extra with the 3x9's, so structurally not concerned where I need to install the headers -- which is in a different area than the "sag / splitting" of concern. As stated above, only issue with 3x9 is best way to attach the tail joist and also hang the header from the adjacent supporting joists.
(Can get hangers but big $$$(quote $11.00-$16.00 each hanger)

joecaption 11-17-2011 07:14 PM

A header is what goes over an opening in a wall, such as where a window, or door is to suppost the area above it, what your doing is adding blocking to support the floor above. Yes, use hangers, there's no other good way to do it with the lumber your working with.
Small price to pay to not have your floor sag.

dw8 11-17-2011 07:58 PM



A header is what goes over an opening in a wall, such as where a window, or door is to suppost the area above it
That's one type of header. Another type is in the floor where the joist is cut to create a opening between two or more joists to accomodate plumbing, stairs, etc. The cut joist or joists is/are called tail joists and the perpendicular support that each tail joist attaches to is called a header.

Blocking on the other hand is placed between two joints to keep the abutting joists standing vertical. In this case no joist is cut.

While I agree hangers would be best, at the cost other alternatives may also work.

One example is you could make your own hanger by drilling the supporting joints.
attaching a two by four with carriage bolts. and then resting the header on the two by four support. Lags screws are another option. Nails will even work.
My objective in posting this thread is to get some feedback from others who have worked with larger size lumber or do timber framing to see what is the "best"
alternative if hangers are not used!

nealtw 11-17-2011 08:05 PM

Make sure you are looking at the right hangers or the right store. You need double 2x10 hangers, the cheap ones. They are for 3".

dw8 11-18-2011 07:30 AM


Looked at Simpson HU38R and HU310R (R designates rough cut); Cheapest price I've found so far is about $10.50 ea (+ tax & shipping).

All times are GMT -6. The time now is 03:42 AM.