Monday, April 23, 2007

They’re Real, and They’re Spectacular

The plaster walls are finished, and I couldn’t be happier with the way the they came out. They are as smooth as glass and will require NO SANDING!!!! Woo-Hoo!

The product I skim coated with is the Diamond Veneer Finish Plaster. It is a completely different animal than the Structo-Lite plaster. The Structo-Lite, which is used in the scratch and brown coats, is comprised of Gypsum Plaster and Expanded Perlite. The Diamond Veneer Plaster is made up of Plaster of Paris, Hydrated Lime, Gypsum, and then it also says it may contain limestone or Dolomite. It warns of it giving off heat when mixing with water, but I didn’t experience this, or at least not to the extent that I could tell. The heat would be from the lime reacting with the water.

The finish plaster sets up very fast. The package says to not make more than you can work with in 30 minutes, but I would say it’s more like 10 minutes. With the Structo-Lite I was mixing a 3:1 ratio with water, and with the Diamond I was mixing it 2.5:1. Some batches were so soupy I had trouble getting the plaster from hawk to trowel. Even with that, once it’s on the wall you can rub your hand across it in less than 30 seconds. It sets up that fast. It’s not hard as a rock in 30 seconds but it’s firm enough you can feel for irregularities.

In the Worley PDF it says to mix some of the Structo-Lite with the Diamond, but someone else who was also taught this method of plastering emailed me a few years back and said they were taught not add the Structo-Lite. I think this was done to increase the working time, but the perlite makes it hard to get a smooth wall. I used straight Diamond finish plaster this time.

Did I mention that I won’t need to sand. Woo-Hoo! I used a similar method for the finish coat as I did the other two coats, only everything was either cut in half or doubled. I mixed small batches of 2 quarts dry mix at a time. You must work fast and you can cover a lot with a batch that small because it is just a very thin skim coat. There was really no time for me to stand back a berate myself over the potentially bad job I was doing. As soon as it’s on the wall and reasonably smooth it’s time to work on it with the sprayer and scraper. Then it’s on to the next batch.

Before you know it, it’s all over. I would say it took maybe an hour and a half to do the actual skim coating. There was, of course, a lot of prep and clean-up. Of course, I WON'T NEED TO SAND! Whoo-Hoo! So the walls are pretty much ready for paint. The packaging does say apply one day and decorate the next. I think I’ll wait a while, though. Exactly how long, I’m not sure. I’m not sure if it will dry completely over night.

The other odd thing about the packaging is that it gives a number of surfaces over which the Diamond plaster can be applied. It doesn’t mention Structo-Lite or blue-board, yet two sources have told me this is what they apply the finish plaster over. More confusion from USG. Also, I had to go back today and buy one more bag of the finish plaster. I asked the guy in the warehouse if they carried any other plaster and he said that was it, just the Structo-Lite and the Diamond finish plaster.

Ideally, I would start putting in the floor tile next, but I only have 60 sq ft of tile ready for installation. I want to get all of it cleaned so I can use the best in the most visible areas. Cleaning the tile is just so hard, though. It’s not something I want to do for hours at a time. I think I may go ahead and paint the walls and put up the crown molding next. I’m not sure.

Oh, and did I mention I won’t need to sand the walls. Woo-Hoo!

One final thought on Lime plaster. As we’ve all heard and read, lime plaster walls must cure for a year before you can paint them. In the book I quoted the other day, it said the reason for this was because the new plaster would absorb the oil in the paint and leave you with a mottled finish. It was said a painter would apply 5 coats of oil paint to the walls. Does any of this sound odd?

First, who applies 5 coats of paint? Well, if you were working with paint that was linseed oil, lead, and pigment I guess you might need to. This got me to thinking about the fact that all that I hear about lime plaster is based on 100 year old information. Would new oil or latex paints be absorbed in to the plaster like the old linseed oil paint? Did they start with a good primer 100 years ago? Maybe not? I’m willing to bet that new lime plaster walls could be painted much, much sooner than their 100 year old counterparts if modern paints were used. Hopefully I will be able to test this theory with the next room I plaster.

Here's some pictures of my walls that won't need sanding {snicker}.

My Mom’s idea is to make a stencil of the design in the window and use it as a boarder around the top of the room.

There will be 1X3 crown molding were the plaster meets the beadboard ceiling


Gary said...

So Greg,
Why don't you tell us ONE MORE TIME just how much sanding you had to do to get those walls silky smooth?

Anonymous said...

Ha! Ok, your title is perfect.

Your walls look great, I'm very jealous. Especially since you don't have to sand. No shower cap necessary ;)

I really like your mom's idea about the stenciling; that window is so cute. You can cut your own stencils out easily, especially if you have access to a light table. You can get a cheap one at JoAnne's or Michaels for around $30.

Anyway, great job. Enjoy the afterglow!

Greg said...


Sanding? Why no, I didn’t need to do any sanding. Why do you ask?


:-) I was wondering if anyone would get that.

I like the idea of the stencil too, I'm just not sure I have the patience for it. I need to get someone a bit more artsy in here to do that. I'm more of a big-picture person.

Mike said...

...and if you got em, flaunt em. Very, very nice! Unfortunately mine are fake.

Anonymous said...

I came to your blog to get information about how to sand plaster walls.

Oh. Nevermind.

Dawn said...

Can you just use the Diamond Veneer plaster to skim coat old plaster? We removed decades old wallpaper in our 1915 craftsman and are down to plaster in areas and some really really old paint.

We just want to smooth out the surface. We may need to do more detailed repair in some cracked areas, but the majority of the work would be smoothing out the walls and ceiling for painting.

Any tips?

Greg said...


I am certainly no expert. For skim coating existing plaster with the Diamond Finish plaster, what I've been told is you should first paint it with a coat of "Plaster Weld" or a similar type product. I would Google 'plaster weld' and see what comes up.

Good Luck!

jacko said...

I'm interested in how the plaster is holding up after 6 or so years...any cracks?

Greg said...

No cracks and that is after a few earthquakes.