Why do homebuilders put plaster on ceilings? Is it just for looks? It just seems like plaster is an invevitable problem down the road when it starts flaking off, compared to just painting the ceiling. Plus you have to be careful not to hit it or the plaster flakes off.
I’m not sure what you’re getting at. If not plaster, then what? Plus, it’s not usually plaster flaking off, but often calcimine, or something put on top of the plaster.
In Connections, James Burke claimed that plaster started as material fill in the chinks around fireplaces and the like that “spread around the room” to seal out drafts and to help insulate. It also makes things loomk prettier than bare wood. The beaten tin ceilings they had in my old school are one possible substitute, but they’re really made as a cheap substitute for handmade plaster decoations.
You could always get a modern drop ceiling, like in my office. But then hordes of Aliens might sneak in over the transom.
Well how about just painting the sheetrock? I assume there’s sheetrock under the plaster on a modern home’s ceiling.
A lot of houses do just have paint (or textured paint) on sheetrock. But plaster is a nice choice – it’s durable and covers a multitude of sins. If you paint, you have to do a ton of prep work to get the joints right and cover the screw holes. The joint where the wall meets the ceiling also has to be carefully taped and sanded. Plaster, being thick, will cover a lot of irregularities that might otherwise show up.
Now I get it. Well, in many cases, painting the sheetrock is exactly what is done. I personally have never really understood the appeal of textured finishes (swirls, sand), but the issue is not really with flaking off. But plaster over blueboard I don’t think has much danger of flaking either. In some ways it’s a nicer finish – you don’t have the danger of sheetrock seams ghosting through, and I think it gives you a little bit more sound insulation, which could be a factor in a ceiling.
The OP is phrased a bit ambiguously, but maybe this will answer it.
Upscale builders sometimes apply plaster to sheetrock ceiling and walls, rather than just painting it. Why? Because a master tradesman can achieve an absolutely perfect edge-to-edge finish with plaster. I’m talking perfectly smooth, even when viewed from sharp angles and with harsh lighting.
View drywall from sharp angles and in harsh lighting–and you can see the occasional seam. Plaster is perfect. That said, it tends to show stress more than drywall.
I could be wrong, but I suspect the OP is referring to popcorn ceilings. The reason they are so commonly used is that they can be sprayed right onto the ceiling drywall. They also hide mistakes in the ceiling drywall.
I recently built a house and had to pay a considerable premium to have my ceiling drywall taped, finished, and painted (as is done with the walls). My wife hates popcorn ceilings.
The reason is because ceilings are very hard to install perfectly, and horizontal light from light fixtures or windows will highlight any imperfection. By spraying a texture on the whole ceiling, the underlying imperfections blend with the texture and you don’t notice it. You can get a good looking flat ceiling, but it’s a lot more work as you need to make sure all the divots and bumps are evened out. Builders love that big popcorn texture since it hides a lot of defects.
They don’t have to be as careful with walls since it’s not as common to have light shining along the wall which bring out the imperfections. The light hitting the wall flat means you won’t easily notice if there are waves, bumps, or divots.
I’ve always had painted sheetrock ceilings and assumed that plastered ceilings were covering lathes. Is lathing not so much of a thing anymore?
Lathe and plaster is almost never used anymore. Heck, even in 1980 my grandparents had trouble finding people who could do it when they built a new home, and insisted upon it. 
Note that this is an old thread raised by a spammer.
Colibri
General Questions Moderator
I’m reminded of one of the fancy rooms in the original wing of Hampton Court. Cardinal Wolsley came back from Italy and said “I want a place that looks like those marvelous Italian villas…”
In this room, instead of a plaster wall like Italy, the wall above the wainscoting is planks of oak 2 to 3 feet wide (those were the days) and painted baby blue to look like plaster. Except, unlike plaster, over the centuries it has dried and shrunk and you can see some large cracks that follow the grain. England had plenty of talented woodworkers but at the time, few plasterers.
In the good old days, plaster was also shaped into ornate finishes, the ceiling decorations and rosettes and such.
Drywall has been used since the 1950’s I think - my house from 1962 was drywall. Certainly quicker and easier to use than plaster on lathe, when (skilled) labour is expensive and manufactured items cheap. It’s kind of obvious that screwing or nailing a sheet of drywall and just doing the joints is far faster than attaching the equivalent amount of lathe, and applying a huge amount of plaster, waiting for it to dry, filling the cracks, etc. As others mentioned, textured ceilings then could be sprayed on and covered a multitude of problems - a nice smooth ceiling with seams not obvious required a certain amount of skill.
What I’ve seen on This Old House is skim-coat plaster over blueboard, which is a type of drywall.
Yeah, even for the plaster look lath is rarely used except in restorations and repairs.
(Shrug.) I’ve never seen lathing in real life, I’ve just seen plenty of scenes in movies and TV where plaster falls off a ceiling or wall and exposes lathing underneath, so I knew it was a thing. Never checked to see that it is a disappearing thing. (I was thinking that the Crack Master was an example, but on review, the boards look too widely spaced.)
I’ve owned homes in different parts of the US and have seen different finishes, all over drywall:
New England, outside Boston: Plaster skim coat (built in 1990)
Midwest (outside Milwaukee): Popcorn ceilings, sand-coat on walls (built around 1970)
Mid-Atlantic, outside Philadelphia: Taped drywall seams (built in 2000)
Southwest (Arizona): “Knock-down” textured finish (one house built in 1994, the other in 2000)
So quite a bit of variation based on local tastes.
One of the other variations depending on locale is round corners vs. square corners. My info is dated as I’ve lived in the western US the past 25 years. The East coast used to be primarily square corners and the West coast has been primarily round corners for the past 30 years.
Textures are almost universally applied to all walls these days as they hide imperfections much better than a flat coat. When I built my house in 2002 The cost for a flat finish was exactly twice as much as an "orange peel" finish.
Wow. No mechanically inclined people here at all!
I used to think plaster was hoity-toity and unnecessary when I was a kid, because it looked like a lot of expensive complicated work.
But I grew up in a world where I have to figure stuff out, an I learned that not only is it not that hard to do a good job plastering a wall or a ceiling, it’s really worth the effort.
For one thing, all modern plasterboard is designed to have the joints plastered, at least. That’s why the boards taper at the edges. So when you skip the plastering, it looks like something isn’t finished.
Some people really like that “I moved in before the builders finished and kicked them out” look, so it’s cool if you are into it, but if a History major can learn to plaster, almost anyone can.
And by the way, if your plaster or anything else is flaking off your ceiling, there’s something seriously wrong with your house. Plaster will stay up fine for decades at least, and some houses have lathe work that goes back centuries.
But go with what you like best. I’ll take plaster every time.
Or high quality wood, but that IS expensive and difficult to do.
What you are describing is the application of joint compound to gypsum drywall. That’s completely different from plaster (either over lath or over blueboard), which would cover the entire wall or ceiling. And the OP was vague, but seemed to refer to a textured finish on a ceiling.