Historic Slate Roofs

Slate Roof Repair

Historic slate roofs are a distinctive feature of many older buildings, particularly those constructed in the late 19th and early 20th centuries. While slate is known for its durability and longevity, these roofs can still experience various problems over time, necessitating repair and maintenance services. Some of the most common issues we encounter with historic slate roofs include:

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1. Broken or missing slates: Individual slates can crack, break, or become dislodged due to weathering, impact from falling objects, or improper installation. These gaps can allow water infiltration, potentially causing damage to the underlying roofing structure and the building's interior.

2. Deteriorated or failing flashings: The metal flashings used around chimneys, valleys, and roof intersections can corrode or become compromised over time, leading to water leaks and potential damage to the roof deck and interior spaces.

3. Failing or deteriorated roof fasteners: The nails, hooks, or other fasteners used to secure the slates can corrode or loosen over time, causing slates to slip or become dislodged, creating openings for water penetration.

4. Degraded underlayment or roof deck: The underlayment or roof deck beneath the slate tiles can deteriorate due to moisture exposure, compromising the structural integrity of the roof system.

5. Vegetation growth: Moss, lichen, or even small plants can take root on historic slate roofs, potentially causing damage to the slates and trapping moisture, which can lead to further deterioration.

To address these issues, our company offers a range of repair and maintenance services tailored specifically for historic slate roofs:

1. Slate replacement: Our skilled technicians can carefully remove and replace broken, cracked, or missing slates, ensuring a proper fit and seamless integration with the existing roof.

2. Flashing repairs and replacements: We can repair or replace deteriorated flashings around chimneys, valleys, and roof intersections, using compatible materials and traditional techniques to maintain the historic integrity of the roof.

3. Fastener replacements: We can replace corroded or failing roof fasteners with new, durable fasteners that securely hold the slates in place, preventing slippage and water infiltration.

4. Underlayment and roof deck repairs: If the underlayment or roof deck is damaged, our team can carefully remove the necessary slates, repair or replace the affected areas, and reinstall the slates, ensuring a structurally sound foundation for the roof system.

5. Vegetation removal and biocide treatments: We can safely remove any moss, lichen, or vegetation growth from the slate roof and apply biocide treatments to inhibit future growth, prolonging the life of the roof.

Our company understands the unique challenges and requirements of working with historic slate roofs. We employ experienced technicians who are trained in traditional roofing techniques and use appropriate materials to preserve the historic character of these buildings. Regular maintenance and timely repairs are crucial for extending the lifespan of historic slate roofs and protecting the overall integrity of these culturally significant structures.

Slate Roof Replacement

GL Barnhart also offers options for replacing an aging or severely damaged slate roof on historic and architecturally significant buildings.  We recognize and understand both the architectural beauty of slate roofing and the dependability and long-lasting protection and durability found in traditional and historic slate.

One option may be to replace the old slate roof with new slate tiles that closely resemble the original roofing material. We work with several natural materials types to provide a variety of slate options, including different colors, textures, and thicknesses, to replicate or resemble the historic character of a building.

Some of the slate options we can offer include:

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1. Traditional quarried slate: This is the most authentic choice for historic buildings, with slate quarried from various regions known for their exceptional quality and distinctive hues, such as the rich grays and purples of Pennsylvania slate or the classic green-gray tones of Vermont slate.

2.  Graduated thickness slate:  To accurately mimic the irregular patterns and depth variations found in traditional slate roofs, we have worked with graduated thickness slate tiles, adding depth and dimension to the new roof.

3. ​Specialized slate profiles: Depending on the architectural style and requirements, we can possibly provide slate tiles in various profiles, such as rectangular, polygonal, or scalloped shapes, to match the original roof design.

While our focus is primarily on preserving the historic integrity of buildings through slate roof replacement, we understand that in certain circumstances, modern alternatives may be a more suitable or cost-effective option. In such cases, we can offer synthetic or composite roofing materials that closely resemble the appearance of slate with high-performance durability, yet lighter weight, comparable installation.

It's important to note that we generally do not encourage the use of modern alternatives for historic buildings or structures unless absolutely necessary and approved.  Regardless of the material chosen, our experienced roofing team follows industry best practices and adheres to strict guidelines for historic preservation projects. We take great care in ensuring the new roof not only meets functional and safety requirements but also maintains the aesthetic integrity and character of the building.

By offering a wide range of slate options and working closely with clients and considering preservation standards, we can aim to strike the right balance between preserving historic authenticity and providing long-lasting, high-performance roofing solutions.