When you're building a new house and have largely progressed things with a particular project builder, everything is extremely high. There are no breakdowns. And it's not just non-standard, just an expected upgrade, of which there were many no sane person would avoid - premium bench tops, better windows, etc. This was $10k in the context of a $200-250k house build.

I grew up in a house with 10' ceilings (most heritage houses in Australia are 10'+).

Yes, there was no question at any point that we were going to do it. Lower ceilings here make a house feel cheap and nasty, so I was thinking of resale value as well as my sanity.

Having just raised the ceiling in my house, there are a variety of things.

Taller walls tend to come with taller windows. Not just more glass... sometimes whole extra windows (transoms) which cost almost as much as the much larger ones below. Taller cabinets or soffit details to receive them. More elaborate trim work. etc.

For a flipper or a production builder every dollar is saved because it adds up in the end. If there's a high ceiling it's because it's been determined to command a good profit.

Yeah, but then there are costs like... umm, I see that smoke alarm at a height of 4 meters above me. I need to go and get the ladder so I can change the battery.

Over here, the standard room height is 2400 mm or 2500 mm, and my house has 2780 mm. I'm happy with the extra overhead space, but there are all sorts of little things. The drywall boards actually had to be ordered separately, and the price increase is not linear. They're heavier to carry - again, not linear - so installing is more difficult. Working on the top parts needs higher scaffolding. To get to the attic, I have this factory-made foldable ladder that opens from a hatch in the ceiling and then folds out with three hinges; it's factory-made for 2500 mm room height so I had to add a 35cm piece to the bottom with another hinge so that it would reach down to the floor and be steady.