It seems like a simple question, but when you work from home there are no simple questions. Determining how you setup your office and whether or not you work in it are subjective and have more to do with the type of work you are doing than anything else. You see, if you need quiet to get work done, than yes, walls are a good thing. If you need to concentrate and limit distractions, walls are a good thing. If you simply need to work and watch the kids or keep an eye on the gardener or roofer, walls become the distraction.
When you work from home you choose how you work best. You have to make the decision as to the type of environment that will inspire you to work productively. This can mean working in the kitchen or at a table in the living room. It can also mean closing yourself off in a spare room, preferably a sound proof one, so you can have absolute peace. What you do, how you work, how you concentrate on things will determine what you need and don’t need in your home office environment.
If you work for someone else, they may dictate how your office sounds. For instance, if you work as a tech support specialist and are required to answer phone calls you will obviously need a quiet home office environment. That usually means walls, but only if you have noises outside those walls that you need to keep out. Not everyone who works from home does so because of family. Some individuals work from home because of physical limitations or personality traits that make it simpler to stay where they are.
My opinion on the question: Are walls required?
No, walls are completely optional. It’s up to the worker to choose the work environment that works best for them.
To me walls are absolutely vital. I love walls and discrete spaces. Flexible spaces that you can turn into anything you want. We have a few here: and two are offices. We have one each – mine is buried far away from the family hubbub. It’s comfortable and almost soundproof. Most importantly, it’s MINE. Do you need walls with teenagers in the house? Duh!