Central beam upgrade

hi flink , my suggestion would be to post some pics of what you have if its possible .

Good thought. I didn’t discover the site until I got to work this morning. I’ll get some posted tonight or tomorrow. Thanks!

ok flink , this is a brand new site so theres not a lot of members yet , but we have an affiliate site that has a wealth of info between the two im quite sure you can get good info

This is far out of my field, but “This Old House” Boston Project last year did something similar to what you were talking about.

-- Thuan

Look into the load carry cap of LVLs or some of the other laminated beams, some them will surprise you with there capacity to carry heavier weights with smaller board, another option is a flitch plate or a 1/4 of steel sandwiched between the 2×10s this can be a rough option if you are in a tight spot but it still might be easier than dealing with I beams.

-- Joey ~~ Sabina, Ohio http://sleepydogwoodworking.wordpress.com/

Hi Flink ,

I am brand new to the site but have run a building and remodeling co. since 1962,and have also tackled some refurbishment projects along the way.

Currently and for the past 15 years, with the exception of my own personal building projects, I have centered on the finishing end of the business, and love raised panel work to chair rail heights, floor to ceiling designs, and lots of heavier [ multi – piece ] custom crown mouldings.

But back to business :

Your idea is achievable and can be put into effect without a lot of hub-bub,..... with a little ” yankee ingenuity, in conjunction with both common sense approaches, and some knowlege of the national building codes.

I have one main question : What is the total clear span under the carrier that you are trying to achieve ?
Followup : Can you live with one center post to divide the weight, or does your situation require that you stay to supports set on 8’ centers ?

Adding a steel plate to the design will certainly stiffen up the carrier beam, help to eliminate sag etc.; but it will not solve the ” let in ” aspect, i.e. [ to bury a portion of the beam into the existing joists ] .

To bury the beam, so to speak, will require a ledger, [ either made of wood, or the installation of a steel shelf angle ].
Code requires that you rest the under cut on somthing at least 1-1/2” wide to provide support to the underside of each joist along the entire lenght of the carrier.

The use of a steel angle ,[shelf angle ], having an unequal leg dimensions would allow you to bolt the longer leg to the beamwhile adding strenghtening and straightness to a less deep member, and provide the joist support at the same time. Note: that you will have too relieve the bottom edge as well as the ajoining face of each joist if you are looking for a flush finish.

Typically this would require a 4 ”- 6” or perhaps even greater long leg, that bolts up to the beam, and a 2’ – 4” leg that would act as the carrier portion under the joists:[ one angle on each side of the carrier.]

If you allow for at least one post midway along the span, this would also provide room to sit each end of the beam, plus the added angles into there respective piockets.

Second approach :

Install channel iron in place of a shelf angle, through bolted to the carrier with the legs out.
This would add the desirered strength, but would involve a little more cutting to let in the bottoms of the joists.

I beam:

While this seems the shortest route, it will require that you have ample space/room to insert one end of the new carrier to enable you to lift and slide the unit into place at the ajacent end.

NOTE :

If you choose to install an I beam for a clear span effect, you would be well advised to have it crowned.
That simple step will eliminate any chance of sag at the center of the span.

Sorry about being long winded, but without knowing the situation I am rather at a loss.

” the exception to the rule should not become the rule “

Norm.

First you’ll have to put up some temporary support on each side of the present beam, allowing enough room

for working. Then you should be able to cut the joists to install an I-beam the proper size. Check with a structural

engineer to get the proper size beam for the load.

-- ** Dick, & Barb Cain *************** http://lumberjocks.com/jocks/Chipncut

Second thoughts:

If your stair is located in the center of the house it would not impede installing a center post allowing you to cut the actual span by half. [allowing two sections, or one full length but lighter beam.

The post by Dick & Barb is right; and you would want about three feet open on each side for working area.

The idea of a steel beam to replace the built up that is there has merit,going to your comment on motivation; but it will entail much more work.

I am assuming that at present, the joists now sit on top of the built-up beam. and that you are looking for as flush a finish as you can achieve ?

The problems that I envision begin with getting the beam itself into the cellar, unless you have a cellar window or other means of access, else you will have to open up a through hole in the foundation to allow sliding the new beam/s in.

By far your biggest challenge will be faced in the cutting of the joist ends, as typically steel beams are seated as the frame goes up, and the joist are more easily cut into place.

You might want to consider the use of an” H ” beam in place of an I section.
Ex. A typical I section carrying two floors, [ two story house ] , and supported at the center of a 36’ span,
would require a section of I beam with a 6” web and 18” depth. The post should be a 30 ton lally column or approved equal.

The ” H ” section seems the most probable choice in this instance; but now you have to take in the weight factor.
While they are stronger, [ width to height ratio ] they are much heavier, and depending on the clear span that you wish to achieve, it will require a lot of help handling each section.

You may have to rethink the clear span issue, as H sections can easily run 30 – 40 pounds a foot or better.
Shortening the span would allow for a lighter section, but would require more posts, etc.

If at present your joists are half on and off, i.e. already rest on a ledger, the cutting away will not be so server; but because this is a retro project you will still have to allow for the full web width, plus.
In addition, you will have to install a continuous ” fish plate ” bolted/welded to the bottom of the section so that the joists have something to sit on, and this should be a reasonably heavy piece of steel, to avoid deflection.

A lot is dependant on your existing joist size for how they will marry up to any beam.

Don’t mean to throw cold water on the project but simply point out some areas of concern.

Norm.

The kitchen sink :

Hi again Flink,
By now you will have realized that this is not the simple job that it may have sounded like at the outset.

I am continuing this because I don’t want to leave you with misinformation, and I will clarify this with the following :
If you live in a one story home the size of the I beam may be as little as 8” over a span of say 10’ or so, if I am not mistaken. Here a steel supplier could set you straight.
If it is one story then the center partition is just that, a dividing partition and not a bearing wall, as the full load of the roof is transferred to the outside walls.
If it is a two story, that partition becomes a bearing wall, and the supports under the joists, on each side cannot extend inward more than two feet off the bearing; but which would still allow you ample room to operate.
I have offered all these suggestions in the assumption that you are at least somewhat versed in building.
Still my best advise to you is that you purchase a building codes book for your area. The cost should be about 48.00 dollars, but you will be rewarded for it in the end.

Unintended consequences :

Once the joists have been shored up and you pry the existing beam down, you will have to sawzall all the nails that came down through the bottom plate. into the sub floor, before continuing. That means that all that will be securing the partition wall from moving, will be the remainder of the 16-d nails that = the thickness of your sub floor. I.e. you should plan on getting some additional fastening into the bottom plate, nailing upwards through the sub floor into the plate, at about the location of the nails that you cut off.

I hope that you find someone with some building experience to help you, in any case.

Norm.