Tar and gravel roofing has been around for many years, and with good success. It is a process by which a combination of asphalt and tar are spread, covering the entire surface, then a gravel mixture is placed over top. This gives it a water resistant surface and a life span of around 15 years. The one big drawback with this type is the fact that the fumes can be overwhelming. Some people have actually had to move out of their house while the new roof was being installed.
Although the tar and gravel rough tends to be about a thousand dollars cheaper for an average sized job, by choosing the torchdown variety you’ll be getting a much better overall finished product, and you won’t have to deal with those obnoxious fumes. Be sure to choose you roofing contractor wisely, as there have been reports in the past of fires being started by some inexperienced roofers laying the torchdown style.