Slate roofing is a popular choice for upscale homes because of its' stylish and sophisticated look, and it's quite possibly the longest lasting of today's roofing materials. Slate roofs last 50-100 years, and often longer. The durability of slate roofing depends on four factors – the physical and mineralogical properties of the slate itself, the way it was manufactured (still done by hand), the installation techniques used and like all building materials, if regular and timely repairs have been done.
Slate comes in a variety of natural colors, with natural variations within each color family. The most common slate colors are grey, blue-grey, black, various shades of green, deep purple, brick red and mottled varieties. Like granite, different colors come from different locations around the world including North America (New York, Vermont and Pennsylvania), England and Wales, Spain and Brazil. That's why the cost of slate varies, along with the fact that much of the manufacturing process is still done by hand.
Types of Slate Roofing
As beautiful as it is, slate is a huge investment which can cost 4 times as much as a traditional asphalt roof. You'll want to look at the cost in comparison to your home's value, and whether slate is the most common type of roofing in your neighborhood. The ideal time to decide on a slate roof is when the house is being built, because the added weight requires more structural support when the roof is framed.
Like many other building decisions, slate roofing isn't as expensive when you compare the investment over the life of the roof. Multiply the cost of 3 or 4 new asphalt roofs, and you'll quickly see that slate roofing isn't as costly. The trade-off you're making is the up front investment for a wonderful, natural material … and less time wasted on multiple roof installations.
But if you're still concerned about the cost, keep reading …
Because so many people like the look of slate, manufacturers have come up with options that are less expensive and easier to install. Synthetic slate roof shingles are made of 100% recycled rubber and plastic, making them environmentally friendly. They're lighter than regular asphalt shingles, so they don't require any additional structural support. The come in a variety of colors and sizes, mimicking that of real slate and they're offered by several manufacturers (see recommendations by Glenn Stone.net).
Another option to get the look of a slate roof at a lower cost is a metal slate roof. Many homeowners like the longevity of a metal roof, and it's ability to shed snow. When they don't like the appearance of a standing seam metal roof, they now have a slate roof option like the one from Interlock shown below.
Who Should Install Slate Roofing
Installing and repairing slate roofs isn't practical for homeowners, as it takes not only roofing experience, but also knowledge of how to work on slate which can be damaged if not handled correctly (see sample slate roofing contract). In fact, most roofing companies don't work on slate roofs because the skills and tools used, are very different from asphalt roofs. Slate is also very heavy, so if you’re considering a slate roof for your home, a structural engineer will need to confirm that your roof framing can support the extra weight.
Repairing Slate Roofing
This article started when a member of the Savvy Homeowner Club bought a farmhouse built in the 1700s, and it had a slate roof. The home inspection indicated there were some issues with the roof, so these home buyers had to decide if they would try to repair the slate roof or replace it. This article started with enough information to assure them it is possible to repair a slate roof and replace damaged slate shingles.
There are two techniques for replacing tiles on a slate roof. This video by SlateRoofCentral.com demonstrates the two different repair techniques very effectively.
- The hook technique – uses a stainless steel or copper slate hook instead of nailing the tile because the other tiles are in the way.
- The nail and bib technique – involves moving the tiles above the replacement tile so that you can nail the new tile in through the gap. This can be done without pre-drilling if it’s an older slate roof, but a new roof or very thick slate roof will need to be pre-drilled so the tile doesn’t break. After the nail is installed, a bib is pushed up over the nail to hold the tile in place by creating friction between the top and bottom tiles.
Do you have any personal experience with slate roofing? Please share below … and thanks.