Brick & Terra Cotta

Basic properties testing in accordance with ASTM C67 is used to evaluate the general quality of new or existing brick or terra cotta. Though Highbridge offers many of the compliance tests in this standard, we most commonly perform compressive strength, absorption, and saturation coefficient testing. Determining these values allows for the comparison to specified brick grades. These properties can also be considered a general proxy for performance and may be used comparatively to evaluate differences between existing masonry units.

Hygrothermal models help move envelope assessments beyond seat-of-the-pants estimates. However, the models are only as good as the data that goes into them. Through testing, we provide our clients with real values of porosity, density, A-value, vapor diffusion resistance diffusion factor, thermal properties, and even critical degree of saturation through frost dilatometry testing. Testing packages can include the full complement of data inputs required by WUFI, or only those values for which the model is sensitive.

Intricately tiled vaults and domes by the Guastavino family adorn some of the most breathtaking architectural spaces. Highbridge characterizes the differential and asymmetric physical and thermal properties of these layered systems to help design teams understand their mechanical and hygrothermal performance. We also use forensic petrography to determine the construction sequence and identify whether centering might have been used.

When terra cotta fails, it can be expensive to replace. Highbridge can aid in evaluating the quality of existing terra cotta, with a focus on material or production issues. The assessment often includes an evaluation of adjacent materials (e.g., grout infill) that may have contributed to the terra cotta failure. We also engage in compliance and quality assurance testing of new production units to give clients peace of mind when selecting replacement materials.

Highbridge can help design a testing scope to aid in your investigation of brick and terra cotta masonry failures. When these materials are cracking, spalling, or efflorescing, laboratory testing can be used to evaluate causes of distress and the potential for further damage. A mixture of microscopic, mechanical, or chemical testing may be recommended to help evaluate intrinsic material issues, freeze-thaw distress, and salt crystallization damage.

Though not technically ceramic materials, Highbridge has experience testing tabby brick, sand-lime brick, and other unusual masonry units in order to better understand their compositions and physical properties. Our analyses provide crucial information for the documentary record as well as for design professionals looking to specify appropriate repairs and treatments.