It was not that long ago that open floor plans were something only the wealthy could afford. It took technology, social advances and a war to change that. Today an open floor plan is the best way to go.
Before Word War II most homes were divided into distinct areas. There was no flow through a home. Each area had its purpose and there was no sharing of space. This was not totally dictated by how people actually lived in a home.
To have large open spaces within a home requires more engineering than a standard home. Homes have what is called load bearing walls. These are walls that carry the load (weight) of the structure above it. To have an open floor plan, you have to eliminate walls. So, where does the load go?
Prior to about 1900, this load could be spread across a large area using steel beams. This works great, but it is expensive. This expense, along with the difficulty of working with steel beams, meant only fancy, expensive homes used them.
Just after 1900, a new technology sprung up - the idea of gluing wood together to make it stronger. This process was used in plywood as well as creating load bearing beams. This process was called Glulam, which stood for glued lamination. This process uses glue, pressure and heat to fuse strips of wood into one long solid piece.
Glulam was easier to work with than steel. It could be cut and modified using the same tools as the rest of the lumber used in the home. Adjusting a Glulam beam in the field was a lot easier than working with a steel beam, which made them cheaper to work with.
While Glulam lumber was used in construction starting around 1935, the big advance came in 1969 with wood I-Joists. A wood I-joist is an engineered wood product. The impressive thing is that they have great strength in relation to their weight. They can carry heavier loads than standard dimensional lumber.
Because I-joists do not bow, crown, twist, cup, check or split like regular dimensional lumber, they are more stable. This means more stable structures and no more squeaking floors. They can also be made to any length and for any load bearing applications.
However even more important than these was the invention and implementation of pre-engineered trusses. These pre-fabricated webbed trusses could cover much greater spans than traditional hand framed rafters. Designers could eliminate many interior walls as they were no longer needed for bearing.
People Love Open Floor Plans
It is not that people in the past didn’t like open floor plans, it was that they didn’t have easy access to them. The technical advancements just prior to and after Word War II made open floor plan homes available to more people. The home building boom after World War II just pushed things further and faster than ever before.
Today we get to reap the benefits of all the engineers, home designers and home builders of the past. We can finally get a home plan that truly flows and allows us to live the lifestyles we were meant to. We are social animals and will always prefer to gather in groups. The open floor plan is a reflection of that desire.