How to Restore a Slate Roof

This article was originally written for the Journal of Light Construction by T Jeff Spencer, owner of slate restoration company Stewardship Slate in Burlington, Vermont.

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I own and operate a small roofing company, Stewardship Slate, which specializes in the restoration and repair of slate roofs. In January, I was contacted by a rental property owner seeking my assessment of a slate roof in Burlington, Vermont. She had recently purchased the 120-year-old house from the estate of an elderly homeowner who, after living in the home for decades, allowed the two-story structure to gradually slip into disrepair. The new owner wanted to keep the slate roof, but numerous contractors told her it needed to be replaced.

Upon inspection, I noticed the roof was in rough shape. Most of the existing terne metal flashings were corroded, and it had numerous broken and missing slates. There was evidence of some dubious repair work done over the years and a fair amount of the historical trim along the eaves was rotted, with most of the corners chewed open by squirrels. Yet, with all wear and tear taken into account, I believed the roof was worth restoring given the life expectancy of the undamaged slate, which I estimated at approximately 75 years. The owner was pleasantly surprised by my quote and jumped at it (she later divulged that my estimate to restore the roof was a third of the lowest quote she received to re-slate the roof and comparable to the quote she received to reroof with architectural asphalt shingles—a 25- to 30-year roof).

For the rest of Spencer's account, click here to read the full article from JLC.