Steel Beams in Remodeling

If you've ever used a steel beam in a remodeling project, then you may consider yourself an advanced practitioner of the trade.

Probably most homeowners aren't aware that steel can be the best choice for a support beam in a remodel project, especially in this age of impressive LVL joists.

But steel beams can make things possible which otherwise could not have been. This is because the density of steel is somewhere around 20x that of wood, and its strength per weight greatly exceeds wood.

Probably the most common situation where steel is used would be when a load-bearing wall must be removed, yet the support must be provided by a member that is very shallow. This is a very typical situation with old houses whose joists may be a true 2×6 or even 3×6, so we only have 6 inches of height to provide support to the ends of many joists. In this case, only steel provides a solution which satisfies the structural and aesthetic requirements.

Here's the view with the studs and joists exposed from the lower floor:

old-wall.JPG

We need to have temporary support going up to each joist on each side before we remove the old wall. A temporary wall could be built on each side, or individual 2x4s could be used on each joist. It is important that we think about the floor below us which will carry that temporary load. Can it handle the load? Many times I have had to put temporary support beneath the lower floor in order to be sure I won't crack joists or tile with the heavy temporary load coming from above.
temp-supports.jpg

Now we need to figure out what piece of steel we can get from our local metal fabrication shop. This will determine how we cut back the joists. In this case I have assumed that we could fit in a standard I-shaped steel beam that is equal or less in depth (height) than our joists.
joists-cut.jpg

Now we place the beam and shim at the notches where our wood joists rest on steel.

beam-in.jpg

Once everything is flat, we can apply the ceiling material below.

ceiling.JPG

One structural fine point: It is often necessary to give a positive tensile (pulling apart) connection between the joists on either side of the beam. (for example, if the subfloor/floor upstairs is a tongue-and-groove type, then the whole system may pull apart depending on pressures eminating from the exterior walls of the house) In this case, we could drill through the steel beam and use a “strongtie” type connection to tie each pair of joists together.