The Art of Slate Roofing

Expert slate roof restoration and timeless quality, no matter the building type, no matter the size.

our lady of peace chapel repair in progress by durable slate

Natural slate has been used to roof buildings for a millennia and was brought to the New World by European settlers where the practice of slate roofing expanded significantly. Nothing at the time – and nothing since, engineered or quarried – has been able to match the durability, essential beauty, and fire-proof qualities of natural slate. Many manufactured products have tried, but true slate triumphs as a roofing material every-time.

Well made and cared for slate roofs are unique historic treasures.

the durable slate company logo viewed on our grey truck from the side

The Durable Slate Company provides slate roof repair, installation, and restoration services world-wide.

We began humbly as a small slate roofing company in Columbus, Ohio, and through a mastery of historic repair methods and a focus on exceptional customer service, we have grown to become one of the largest slate roof repair companies in the United States with offices located throughout Ohio and Maryland, including Columbus, Cleveland, Cincinnati, OH, and Savage, MD.

We service the entire United States and Washington D.C.

copper flashing and metal seam in slate roof

Thanks in no small part to our extensive repair experience and history, The Durable Slate Company is able to handle any slate roof repair or installation of any size on any kind of building.

And with such a large stock of reclaimed slate in America, we can match most slate for an exceptionally seamless repair or full roof replacement. If your slate roof has been damaged by fire, wind, storm, other forces of nature, or just requires a bit of upkeep, you can be confident in The Durable Slate Company for your slate roof repair needs.

a closeup of a copper finial recently repaired by durable slate

Reclaimed slate can also be great for new installations, allowing a wonderfully aged and classic look, without having to wait a century. Likewise, if an antique roof’s slate shingles are in good condition, it is often possible to install new underlayment and copper flashing, preserving the original slate, and matching damaged tiles from our reclaimed slate stores.

A thorough evaluation by a professional is provided by The Durable Slate Company at no additional cost to you to determine what is best for your slate roof.

our lady of peace work in progress, copper flashing

For installations with new slate, we prefer to install only the highest quality time-tested slates from the quarries of the Vermont Slate Valley, Virginia Buckingham, Southeastern Canada, Wales, and certain select European quarries. The combination of high quality slate, expert flashing design and installation, correct soldering, necessary underlayments for the conditions, and proper slate laying and fastening produces an aesthetic, long lasting roof that should have a serviceable life of 100 years or longer.

All Saints Episcopal Church as seen from the front, wide view

Cutting corners on any one of these factors can shorten the life span of a slate roof from a century to a few years or less. We have replaced numerous slate roofs that were less than 10 years old because an essential craft was neglected.

Though quite beautiful, many imported slates are of such poor quality that they start rusting and falling apart within only a few years of installation.

A high quality slate is essential.

copper step flashing installation

Even with a high quality slate, problems can arise when protrusions and transitions are not handled expertly as these are the areas that tend to leak the most. Allow our experts to explain how these and other factors are important for your particular project and don’t get fooled that all slate roofs are the same.

A slate roof can only stand the test of decades with correct design, knowledge of the correct procedure to install these materials, and the skill to do it expertly.

Common deficiencies found in slate roofs installed by novices include:

  • Poor quality slate (can be from low quality quarry- a large percentage of imported slate, or low priced brokers selling seconds- i.e., slates that are warped, high amount of quartz veins, cut when the stone was too dried out, etc.)
  • Uncropped and nailed valleys Under and Overnailing
  • Using non-solderable metals that have caulked seams
  • Long expanses of metal without control joints
  • Too large of pieces of metal used in areas which require flat lock installation
  • Inexpert/incorrect soldering technique
  • Soldering joints that are not cleaned, pre-tinned, well soldered, and neutralized- especially at critical points
  • Soldering with too cool of an iron or too hot of a flame as in an acetylene torch resulting in seams that are “covered” with solder but with seams not filled
  • Incorrect headlap and/or sidelap
  • Incorrect installation of step, apron, and counterflashings
  • Use of warped slates especially when laid improperly
  • Nailing long pieces of metal resulting in stress cracks
  • Installing over insufficient substrate (rotted, too thin, poor quality, too much flex, etc.)
  • Exposed nails left from roof jacks Use of asphalt and caulks in a way that traps or backs up water flow
  • Design for water flow that does not take into consideration settling and movement of building, capillary action, wind, drainage, or ice-damming
  • Hairline cracks resulting from excessive traffic during installation
  • Wrong type of nail
  • Incorrect underlayment installation