Authentic Or Replica?: How To Tell If Plasterwork Is Original

Historic buildings and homes are highly prized for their original features, including plasterwork such as decorative cornice moulding. However, it can sometimes be difficult to know if the plasterwork is original to the era the building was constructed, such as the Georgian or Victorian period. 

This distinction is important, because it will affect the type of restoration and maintenance work the plasterwork requires. It will also help you to understand and appreciate the character of the building and others like it in more depth and detail. 

Assess the style of the plasterwork

The biggest clue to accurately estimate the age of the plasterwork is to assess the style and design, as each era produced distinct artistic traits. For example, the Georgian era (1714-1837) favoured elegance and simplicity of design, sometimes featuring friezes with classical motifs. 

Victorian era (1837-1901) plasterwork tends to be more elaborate, often featuring ornate floral designs, scrolls, or animal motifs. The Edwardian era (1901-1914) saw a return to simpler and more restrained patterns, with sophisticated clean lines and subtle curves. 

Find out the date your property was built, and consider if the style of the plasterwork is consistent with it. 

Examine the plaster

Older plaster tends to be made from a mixture of lime and sand, and it tends to be softer with a more porous texture. It may have a cream or yellowish colour as a result of its age, and the surface may have fine fissures or crumbling patches. If you gently touch the plaster, you may find that it is slightly chalky or powdery. 

Old plaster was often mixed with horsehair, particularly the initial layers, so you may spot evidence of this in any areas of deterioration. Newer plaster tends to be made from gypsum, which has a smoother surface and a harder texture, and may be whiter in appearance. It’s more lightweight and does not contain sand or hair. 

Consider the installation techniques

Inspecting the plasterwork closely will give you some insight into the installation method, which can help you to accurately pinpoint the date. For example, older plasterwork was often installed in sections because it tends to be heavier, so you might notice evidence of joins. 

It may also be slightly asymmetrical or have other slight imperfections, because it was handcrafted rather than cast in a mould. It may also show general signs of age and wear and tear, such as hairline cracks and discolouration. There may also be evidence of previous attempts at repair, such as patched up areas. 

Overall, it’s often possible to make a reasonably accurate guesstimate of the age of plasterwork by inspecting its condition, style, and craftsmanship. However, some replicas are very convincing, and old plaster that has been painted over can also be misleading. If you are in any doubt, it’s best to seek professional advice from a historical plasterwork specialist.