Slate roof repair, including partial or full slate replacement, should be done by a slate roofing professional.

Damaged slate may be removed without replacing the whole roof. There are three recommended strategies for replacing or maintaining individual slates. A “nail and bib repair” uses a nail covered with flashing to secure the new slate. A “slate hook repair” uses a small copper or stainless steel slate hook to hold the slate in position [2]. The third option is to flip the slate so that the original nail holes are now exposed. Covering the exposed and weathered side of the slate in this manner extends the material’s life. Weathering, severe cracks, or breaks related to impurities or physical deterioration may mean that the roofing slate is compromised preventing one from simply flipping it [1].

It is not productive to simply apply tar or roofing cement to a weathered area of slate. The use of this material on slate can prevent what could be an easy repair in the future, and is aesthetically displeasing [2].

New slates should match the originals in kind, including in size, shape, texture, and weathered color of the slate [1]. When possible, replacement slates should come from the same quarry as those being replaced. One must try to remove slates carefully so that good pieces may be reinstalled or recycled.

If more than 20% to 25% of the slates are damaged, replacing the slate roof may be more practical than replacement of individual slates [3].

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Inherently Sustainable Features (ISF)

Preservation and Conservation Strategies

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