The answers to that question probably aren’t going to offer very many surprises, but the one factor that does surprise people is how quickly a new slate roof can fail. It can happen in as little as 3 years! Most owners of a bad slate roof learn that lesson the hard way but if you’re one of the few people who ask this question beforehand, congratulations.
This is going be less about why a slate roof can fail so you can avoid having it happen, or worse, having it happen again if you’ve already been burned. Knowing why they fail does equip you to avoid the heartbreak and expense of a failure.
Not all slate is created equal
In other words…quality. Slate is a natural product. Many people falsely assume that because slate is mined from the earth, it is essentially all good. That is very incorrect. The facts are that slate varies widely in its resistance to moisture and water absorption, delaminating, its stability and longevity, and its overall suitability for being used on your roof.
Another factor that is not helping your situation is that testing slate quality is voluntary so a great deal of slate being sold on the market isn’t tested, or it is only tested for a standard used to mislead uninformed buyers. The downside for natural products is they don’t have the same accountability that applies to the manufacturers of manmade roofing products.
There are stringent testing standards like the French NF30 which is generally regarded by experts as the most rigorous testing standard in the world. Having slate tiles that pass tough testing standards may appear to make them cost more, but the reality is, if you don’t have the right slate quality installed, you’ll just spend money on better quality later, and that’s the real expensive option.
Poor quality workmanship
Again, no surprises as we state the obvious, but unqualified slate roofers are at least as bad as poor quality slate material. We dedicated much of our previous post (and other posts) into some basic rules for qualifying a good slate roofer, but because so many new slate roofs in the Melbourne area have suffered the consequences of poor quality workmanship, we can’t overemphasize how important this is.
Melbourne is subject to torrential downpours. That’s what makes slate such a great choice when quality tiles are properly installed. But improperly installed, all the benefits get cancelled out. Melbourne is also subject to some high velocity winds. Properly installed, your slate roof is like armor plating. But poorly installed your slate tiles can become dangerous projectiles posing a serious threat to persons and property.
Climbing on the roof
Slate roofing will withstand everything nature can throw at it better than any other roofing material. People on the slate roof does not fall under the nature category. You should consult with a slate roof professional before anyone climbs on the roof. A satellite dish, skylights, or a better view are not worth ruining your slate roof for.
