From the mid-1800s to the early 1900s, slate was one of the most common roofing systems in the United States. A typical slate roof system may provide a service life of 75-100 plus years and some have been documented to last up to 200 years with proper maintenance.
The cost to replace slate roofs is high compared to other steep-sloped roof options, and lead times for slate can be long. Historic preservation guidelines encourage repairs before replacement, so it is critical for building owners and designers to understand when repairs should be performed, how repairs should be performed, and when a roof is beyond repairing.
This presentation will provide valuable information regarding slate roofing’s history in the United States, historic preservation guidelines and recommended repairs, and design considerations for slate roof replacement projects.