Every week Scott Roofing in Nevada does residential re-roofs on existing homes. With the influx of satellite TV over the years we have encounter more and more dishes mounted to or near the roofs. It appears that the satellite installers all have a little different idea on where to mount the dish. From a roofers view, we would always love to see the dish mounted somewhere besides directly through the composition shingle roofs. When mounting to the shingle roofs, holes must be made in the roof to accommodate the fasteners. When holes are made through the roof shingles they are most commonly sealed with a caulking of some type. Whenever a caulking is used in this capacity it becomes a maintenance issue. Even with the dish mounted in a non-living area like the overhang, water intrusion can cause damage to the plywood sheathing or the structure in that area without the proper maintenance.
Alternatives to this issue are starting to be addressed by satellite installers more recently. We have started to see fascias and siding as well as free standing posts being utilized in many areas. Many of these areas have tile roofs exclusively and those make it impossible to mount a dish through. Scott Roofing in Reno would suggest when having a dish installed that the customer ask the installer to treat it as if it was a tile roof and therefore eliminating any damage to an existing or new composition shingles.