Natural versus Synthetic Slate

October 7, 2008

Lately it seems that people are quick to endorse synthetic slate roofing materials without much history to support their approval. Some people rave that synthetic slate is much cheaper than natural slate, lighter, more durable, has a 50+ year warranty and it’s typically recycled. But it seems that few people mention its fading qualities and the fact that the majority of these products have only been around for about 15 years. In my opinion, these materials are simply too new to commit to a “life span.”
If you have a natural slate roof, you should really try to stick to the real thing no matter how tempting a faux product might seem. This is especially true when maintaining the historical integrity of your home is a priority.

Sharon Park, FAIA, senior historical architect for the National Park Service Technical Assistance Division, suggests contacting your local historical commission, if there is one, and with your State Historic Preservation Office to ask about possible substitute slate for your roof. This is required if you plan to cash in on tax credits for home rehabilitation in states that provide them.

The fact is, nothing beats the durability and aesthetic value of a natural slate roof. It takes regular evaluation by an expert to uphold the quality and appearance of a natural slate roof. Winter can be an especially harsh time for a slate roof if it did not have the proper underlayment put in upon installation. Since the majority of people were not the homeowners when their slate roof was installed (they can last up to 100 years or more), it is something all homeowners should get checked out. Having the proper underlayment and high-back gutters can prevent thousands of dollars worth of water damage later on.

Below is a picture of a relatively new synthetic slate roof. If you look closely you can see many of the tiles have curled. This would never happen with the use of natural slate.
If you haven’t already, you really ought to network with local restoration architects and contractors, especially those familiar with your area. In order to maintain the historical integrity of your home, all repairs should be done with materials that match the originals as closely as possible.