This one is a little blast from the past – more specifically, March 2010, Montpelier.  We installed 30 year Owens Corning architectural shingles (Estate Gray) right over the top of the existing shingles.  This saves time, labor cost, and a huge clean-up headache.  However, be aware (as this homeowner was) that this will void the manufacturer’s warranty.  This is not a big problem, as architectural shingles today are of much better quality than the old 3-tab monsters from a couple decades ago.  This homeowner will probably get 25-30 years out of these shingles regardless of the installation.  Give me a shout for a FREE ESTIMATE!  419-212-3200