No, this isn’t a post about the emotional intelligence of structural beams. Instead, let’s consider the different options for removing a wall, and how those choices look and feel in a finished room.
When your Architect has determined that a wall is a structural or load-bearing wall, what does that really mean? Usually, it means that the wall is holding up either the roof or the floor above. The easiest way to see this is to look at an overhead garage door. The skinny piece of wall above the door and below the ceiling is actually a beam. We call it a lintel if the wall is concrete block, and a header if the wall is wood frame. Nevertheless, the beam is holding up that part of the house above the garage door. Either the ends of the roof rafters or the ends of the upstairs floor joists actually sit on top of that beam.
Garage doors have beams to hold up the house above them. And so does each window pictured here.
So, if we wanted to remove a load-bearing wall, we would have to replace it with a beam. This is where the aesthetics, or the look and feel of the room, comes into play. Installing a beam that is below the ceiling line, like the beam over the garage door, is called a dropped beam. It is dropped below the ceiling line. It does a perfectly good job at holding up whatever is above it. But, it has the tendency to act like a divider. You are either in a room on one side of the beam, or on the other. In fact, it would probably feel uncomfortable if you were sitting directly under the beam. So, not the best option if the beam is over the center of a large new room.
This dropped beam gives the feel of dividing this dining area from the seating area, even with no wall between them, and the same flooring.
Enter the up-set beam. She is actually quite happy to disappear into the ceiling and not be seen again. In this case, the beam is also holding up the house above, but you could only see it in the attic. The ceiling is flat and flush. This makes for a wonderful, open floor plan with a continuous ceiling plane.
However, the up-set beam can cause trouble if it’s not thought out in advance. Because if the up-set beam is very long or very tall, it might want to bump up through the roof. And we can’t allow that. So we carefully plan the addition to allow for the entire beam to be hidden up in the ceiling or attic. We also check that the air conditioning ductwork has enough space to maneuver around the beam in the attic.
One last consideration before choosing an up-set beam is how it will hold up the house above. Because the roof rafters or upstairs floor joists used to sit on top of the old wall, they are now too long if we put the beam up there. So, we typically saw off the ends of each rafter or joist, and then attach them to the side of the beam with hangers. They used to sit on the wall, and now they will hang from the beam.
Erasing the beam quickly shows the effect of an up-set beam hidden in the ceiling.
Finally, you may be wondering what kind of material are these up-set and dropped beams? Well, they can be many materials, so let your Architect choose, with some input from the Contractor. In residential projects, we typically stay with wood, as it is less expensive and not as heavy as other options, and easily fastens to rafters and joists. We may specify regular lumber, like several 2x12s joined together, or an engineered lumber like an LVL, made of multiple layers of wood laminated together. For concrete block walls, we typically use pre-cast concrete lintels, which are formed at the factory with an empty middle for the steel rebar and grout to be placed. Lastly, a steel beam may be required because of the weight it needs to support, the long length it needs to span, or other reasons. Steel is more expensive, and a little more difficult to install and attach to, but can be the best or only option.
So, once you understand the options, don’t hesitate to ask your Architect about knocking down a couple of walls.
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