It being an office building, you likely did not have nearly the level of environmental control I describe.
I do really hate sunlight, but fresh air is essential. If you don’t have fresh air indoors, your HVAC design is bad. Air is one of the easiest things to move around.
I’m doing precisely that, but I have simulated the same in the meantime by taking a normal residential house and completely blacking out and sealing the windows in the largest upstairs room. It’s excellent. When I turn off the lights it can be pitch black and 68F at noon in the middle of the summer in the Mojave.
I had to cover the windows in all the adjacent rooms to make this work, but it does.
It wouldn't be too expensive to make what you want, you could always buy a small plot of land and build a custom home to try it out. Shouldn't be more than $200-400k, possibly less depending on the area.