Are the interior support walls in houses actual walls of support?

Yes.

If it’s a load bearing wall then it’s supporting at least some of the weight above it. Not all walls are load bearing. I’m not really sure what you’re asking.

Here’s a picture of load bearing and partition walls

@Tropical_Willie I think from your diagrams it’s just load bearing columns and then regular framing and drywall make up the rest of the wall. Is that right? So, you could open up the wall most likely, put a doorway for instance, and not disrupt the load bearing elements.

@JLeslie You’ll need an engineer to tell you if a wall is structural. If not, it’s easy to put in a doorway. If it’s a load-bearing wall, they’ll have to put in reinforcements over the doorway to transfer the load; it will probably require temporary bracing to support the load while the work is being done too.

@gorillapaws If I did anything I would use a professional. Isn’t there a beam across the top of the wall already for support?

“Isn’t there a beam across the top of the wall already for support?”

No! there are studs going from the top of the wall to the floor. Engineered beams can cost thousand plus installation.

@Tropical_Willie Are studs what I am calling columns? I don’t know what to call that. So, they aren’t 3’ apart, is that right? Can’t get a door between and still have support for the upper floor?

https://en.wikipedia.org/wiki/Lintel

Double stud and lintels for doorways and some windows put in outside walls.

My grandfather and several uncles were carpenters, they help my father build a house in Los Angeles in late 1940s.

Hopefully this explains how it works:
https://www.askthebuilder.com/enlarge-opening-in-load-bearing-wall/

If you are not 1000% sure, Get an architectural engineer to review prior to doing your own demo work.

Just to clarify, there are two types of walls in a house: partition walls and load-bearing walls. It requires an engineer to know which-is-which. You can knock out all of the partition walls in a house, and it’s not going to really have an impact on the structural integrity. If it’s load bearing, then your going to need to transfer the load that wall is supporting somehow (usually with structural beams (that are often enclosed in the walls). This also requires an engineer to crunch the numbers to know how big of a beam is required. 2×4 studs and the top plate (the 2×4 running horizontally on top of the studs) isn’t enough to support a second floor/attic/roof on its own. Your talking about a lot of weight.

I’m only talking about load bearing.

I’m not knocking down any walls on my own don’t worry.

I only was wondering if load bearing walls typically have the supports a few feet apart across the wall that a doorway can easily be cut out, but it seems the answer is no, the supports, or columns inside the wall are typically closer together.

In Florida our one story homes typically have no interior load baring walls so I just wasn’t familiar with what they are like behind the sheet rock.

We put in a bid on a house in TN that we would have wanted to widen a doorway, but I think part of the wall was likely load bearing. We were outbid. We put in an offer $100k over asking! Other bids were $200k and almost $300k above asking. The market there is insane.

Doesn’t matter about the TN house, because I want to know about the walls for the future anyway.

When I think of the house I grew up in (3 story including basement) there were single columns in the basement helping to support the house that were far apart. There were likely support “walls” also.