Plaster & Stucco

Just as we are known for our expertise in mortar analysis, Highbridge is also regularly called upon to evaluate the composition of stuccos and plasters. We adapt ASTM C1324 to identify materials and mix designs in these layered applications. In modern stuccos, this testing is used to determine whether these comply with specifications. In historical mixtures, we encounter a wide variety of materials. Not only can we use this testing to quantify proportions of these mixes, but we can also distinguish specific binders from Keene's cement to plaster of Paris to cement plaster.

Our staff is sensitive to the challenges of art conservation. With architecture, it is usually possible to acquire samples sufficient to meet the statistical rigor of most test methods. This is almost never the case when works of art are incorporated into the architecture. Highbridge has a deep understanding of the materials and methods used in architectural art. Moreover, we can guide our clients through conservative sampling strategies designed to answer the more relevant questions regarding a material’s composition and its interaction with the environment.

Calcined gypsum is a versatile material that has found application throughout construction past and present. Wood fiber-reinforced gypsum concrete has been used for decades as lightweight roofing. Gypsum-based leveling compounds are popular options for flooring underlayments due to their thermal and acoustical properties. When our clients need to know more about unique gypsum-based products and their condition, Highbridge uses petrography and chemical analysis to characterize these materials and evaluate their performance after installation.