History of Lath and Plaster (2011) [pdf]
marekbros.com
marekbros.com
> Starting around the late ’70s and well into the ’80s, the industry had a perfect storm brewing. The trade unions began to lose market share at an alarming rate. As a result, apprenticeship training began to slide until only a handful of trained people hit the market and they found themselves outnumbered when flashing procedures were discussed. That meant a lot of tradespeople lost the clear, simple and universal direction on flashing a window. New, untrained craftsmen thought the flashing procedure was unnecessary. Architects started to draw with AutoCAD systems and many classes on basic building practices had to shift to this new technology of point plotting and learning the software programs. Something had to give way and it did—the construction details.
> ... While some have thought lath and plastering would die out, it continues to be reinvented while holding onto its roots. For the lather, tying of wire has given way to the modern screw gun, and modern plaster pumps would seem to make the hawk and trowel obsolete. However, the traditional tools and materials of the lath and plaster trade seem to be able to make room for modern innovations while keeping their place as relevant today as they were over a century ago. Designers are encouraged to explore new innovations and are charged with not allowing the past to die out with regard to lath and plaster.
With a few exceptions, plaster walls are vastly superior to drywall. USG, which makes drywall and plaster products, more or less rates lime plaster as the gold standard in a lot of ways: https://www.usg.com/content/dam/USG_Marketing_Communications...
How do they describe drywall? "Relatively smooth surface with acceptable monolithic- appearing finish under most conditions. Lowest cost."
Conventional plaster: "Best system for attaining a uniform, monolithic, blemish-free, smooth surface with excellent wear resistance."
They're understating it. Drywall is garbage. Plaster (especially if mixed in certain ways) blows it out of the water with regard to sound isolation, fire resistance, mold and water resistance (more lime than gypsum plaster), and just plain beauty and character. It even has a nice thermal mass and if you put perlite in it, some insulation properties (you'd still want real insulation of course).
And yet even very nice and expensive houses I see are drywalled. It's so ugly! People don't know what they're missing. Most have probably never seen a good plaster job that doesn't have 50 years of paint on it. I'd value good plaster work on a new house much higher than easy shit like granite countertops.
The only real pain is whenever you decide you need to cut a hole in it, the damn stuff fights back, and good luck finding people who know how to do it. I did my own plastering in a bathroom...I sucked at it, but still worth it.
I need to find a copy of the "Plaster and Drywall" book. It's interesting to see an organized education and lobbying association which has carried a flag for decades, is recognized by academia, industry and regulators, and encompasses both centuries-old technique and modern code compliance. It's like an "Association of Assembly Language and Rust Developers".
Hopefully the craft of plastering will continue be preserved and extended as a side effect of historic building preservation, https://www.oldhouseonline.com/repairs-and-how-to/repairing-...
> This publication has been prepared pursuant to the National Historic Preservation Act of 1966, as amended, which directs the Secretary of the Interior to develop and make available information concerning historic properties. Technical Preservation Services (TPS), Heritage Preservation Services Division, National Park Service prepares standards, guidelines, and other educational materials on responsible historic preservation treatments to a broad public.
> Plaster in a historic building is like a family album. The handwriting of the artisans, the taste of the original occupants, and the evolving styles of decoration are embodied in the fabric of the building. From modest farmhouses to great buildings, regardless of the ethnic origins of the occupants, plaster has traditionally been used to finish interior walls.
I also had a book on historic preservation (Practical Building Conservation: Mortars, Renders and Plasters) and read through data sheets from places like USG.
It's hard going because so few people do this, so finding proper materials can be difficult, particularly if you're being bizarre as I was and trying to do proper three coat. Horse hair wasn't readily available, for instance, so I used some hemp fibers, etc. There is also a resurgence among people who want more 'natural' building materials.
I added some plaster arches in a part of my house to subtly demarcate the space. It totally changed the character of the house and because it was plaster, they looked original (the house was from the 30s). It wasn't my original intent to put arches there, but I wanted to hide some wiring that I couldn't easily repull.
I think it probably helped sell the house.
in fairness, it's harder to repair correctly, especially for large damage, though i have patched the wall myself with anything from patching compound to joint compound to spackle (which i understand as being similar in its constituent ingredients but not quite the same).
It kills me when people replace plaster with drywall. Sometimes they'll even have it all torn out and replaced because they just need to do some repair or are doing a renovation and just want all the mess to happen up front and tacking drywall up is cheap and easy later on. So stupid.
In my last house I retiled the tub and behind the tub they had mold-resistant drywall that they used as a tile substrate (this isn't proper, but it's common enough that people think it's proper.) The drywall was nailed into plaster, which itself was covered in wallpaper. Taking all this down to fix it I found the wallpaper and drywall was moldy, but the plaster itself was not moldy. The spores just wiped right off. It's great stuff.
when i was researching how to repair plaster, i learned that old-school plasterers used to make 3 passes to make it perfectly smooth on top while thick and sturdy throughout, starting with a rough "brown" layer for the bulk to a fine white layer for aesthetics and water resistance. it takes skill to do but the results are both visually pleasing and resilient (having lasted ~100 years so far in my building).
Making the final wall true when dealing with imperfect framing is done with the dot and screed method. You can also add dyes into the finish coat and leave it unpainted. Shame plaster has died out for most construction.
1931: CLPCA publishes the "Historical Digest of Plastering".
1976: The Plaster and Drywall Systems Manual is published and used as a text book in many architectural schools.
2014: The fifth edition of the Plaster & Drywall Assemblies Manual is published.