Colonial Williamsburg – Benjamin Powell Smokehouse

Project Background:

• Located in Colonial Williamsburg, a member of the National Register of Historic Places and a US National Historic Landmark District
• One of the original 88 properties of Colonial Williamsburg and the only surviving brick smokehouse
• Until 1984 the building was still fully functioning, demonstrating the traditional methods of curing and smoking meats for over half a million annual visitors

Challenges Presented:

• The smokehouse had suffered severe deterioration of both brick and mortar due to salt crystallization within its walls and was unstable
• Local birds were actually eating the salts from the exterior walls, further damaging the structure
• Mortar deterioration was so severe that repointing of the mortar joints was required almost semi-annually
• Due to the irregular patterns and rate of deterioration, architectural conservators were hesitant to implement conservation measures without a clear understanding of the underlying processes taking place and their effects

Services and Solutions:

• Masonry Solutions’ laboratory engineers began by using non-destructive evaluation techniques, including ultrasonic and mechanical pulse velocity surveys and infrared thermography scans to study the structure
•  Pulse velocity surveys indicated severe internal deterioration not visible by other means
• MSI personnel utilized their findings to develop a unique poultice treatment that would remove salts from the interior walls
• Masonry Solutions formulated a CIF mix that would match the characteristics of its historic host
• This CIF mix was injected under very low pressure to ensure the walls were solidified and provided monolithic performance
• Then MSI techs carefully applied their custom poultice treatment, utilizing a protocol that would not leave any changes in the building’s appearance upon completion
• Once applied, a de-humidifying system was installed at the interior to draw moisture to the poultice, capturing the salts in the process
• Initial poultice samples were collected and tested to quantify the procedure’s performance
• A total of 4 poultice treatments fully eliminated the smokehouse’s salt crystallization issues, stabilizing the construction and preventing future structural decline
• Further NDE verified that the voids were indeed filled and that the interior condition of the walls was greatly improved