Avoiding Sub-Standard Slate Products
An individual looking to purchase a slate roof should be educated to ensure that he makes the correct choice when selecting roofing slate products. All slate that is produced in the world is inherently different and while some are excellent, others are plagued by a host of impurities and poor quality. A slate roof is a substantial investment and a potential buyer must treat this decision with care. Once work begins the quality of the slate purchased will become immediately apparent. There may be a high breakage factor in transit, the slate may have a high number of unusable pieces due to presence of veins in the slate, causing the roofing tile weaken and break with minimal handling. Buying poor quality slate will ensure a high number of waste slates and it is likely that the installed roof will be of substandard quality with a diminished life span.
A slate roof should be an investment for the life of the property, and the owner should be pleased with the quality of the individual tiles and the roof as a whole. A properly installed, quality slate roof is a satisfying and value adding addition to any structure, while an improper installation will nullify the effectiveness of even the best quality slates. It is critically important to contract a roofer who is experienced and skilled with installing slate roofs. Extras such as copper nails and copper flashing are also necessary to ensure the quality and service life of an effective slate roof. As with any investment one must be careful to choose a quality product. Minor initial savings with inexpensive slate will lead to a host of problems and result in an unsatisfied customer. Our goal is to educate potential slate roof customers to identify quality slate products and make an educated choice in order to receive a quality end product.
Any potential client for a slate roof should first request a sample from each prospective roofing slate supplier. There are certain laboratory tests run to ascertain the quality of roofing slate. These tests are performed in an ASTM approved manner. Three tests are run on slate samples: flexure testing, water absorption and acid resistance.
These ASTM tests can only serve as a guideline, but a conscientious customer can compare samples that he has received. By handling the slates a customer can easily identify undesirable characteristics. Does the slate flake or scale on the surface with minor rubbing or picking? Are the beveled edges nearly vertical? If so this hints of a softer slate because the slate cutter has easily gone through the roofing tile. Are the beveled edges strong; or can one take a thumbnail and pick the material from the edges of the slate? Finally, run the slate under some water rub; check for flaking, and then dry. If the slate is still damp to the touch after a few minutes, the slate has a higher rate of water absorption which will lead to premature wear during the freeze / thaw cycles.
While these are only rough guidelines, hopefully this knowledge and information in this site will lead to a customer making a more informed choice in such a major investment.