and is there such a thing as “Portland cement Stucco”?
In modern terms, portland cement plaster and stucco are one and the same.
Stucco is the finish coat of a portland cement exterior plaster system. The basecoat (nominal 3/8" thick) is the “scratch” coat. The intermediate coat (nominal 3/8" thick) is the “brown” coat. The finish coat (nominal 1/8" thick) is the “stucco” coat. See ASTM C926 which covers “requirements for the application of full thickness portland cement plaster for exterior (stucco) and interior work.”
The term “stucco” is often used in a broad sense (erroneously) to indicate finish systems that duplicate the appearance of portland cement plaster, such as EIFS or DEFS (thin-coat sythetic plaster). True stucco is a built-up system as John describes above. While portland cement stucco might be redundant, it does differentiate from the imitators.
Several of our clients have asked that we no longer refer to it as Stucco, but rather Portland Cement Plaster citing ASTM C 926 to avoid confusion - semantics, semantics, semantics!
FWISW:
1779: Inventor Bry Higgins receives a patent for concrete stucco.
1824: British stonemason Joseph Aspdin makes kiln-fired mixture of clay and ground limestone on the Isle of Portland, dubbing his creation “portland cement.”
Source: May 2008 issue, This Old House
In reference to a brown, scratch and topcoat assembly, we provide a definition that “the work of this Section may be referred to as Stucco”, just to close the loop and avoid tiresome RFI’s.
In other Sections we have a similar comment regarding “curtainwall” and “windowall” in reference to aluminum framed glass and panel systems. I have heard each used in a single sentence in a trailer meeting, by the manufacturer’s rep no less, so I might as well give up.