Safe Roof Mounting for Antenna and Satellite Dish
The picture below shows an example of one of the antenna mounts, to the side of a chimney. The antenna is strapped or installed with bands around the chimney itself. There are different methods of installation, both at the chimney, and at other types of configurations for mounting satellite dishes and or historic antennas. In most cases, it’s better to simply remove the antennas.
Today, in modern times, they are almost all abandoned and unused. Yet they remain on top of the roofs because most people don’t bother messing with something if it isn’t broken. When the antennas break though, they generally fall down and have a tendency to pierce through the roof membrane when they fall. That costs additional money because it’s an unnecessary repair to the roof of the membrane. It will also normally lead to leakage on the inside of the building which will also need to be repaired.
Our company mostly focuses on the damage on the outside of the building, where roof is damaged and door deteriorated. In most cases though there’s also a secondary effect to roof leakage. That secondary effect is the damage to the plaster and your finishes of the building on the interior. Where buildings have been significantly neglected, the amount of damage on the interior related to water entry through the roof can be astounding. Sometimes it can lead to the ruin of the building.
In this particular case stainless steel bands have been used but they aren’t actually fastened, just tightened under pressure. They may have loosened or weakened over time though you can see that pieces of 2×4 wooden boards and additional loose bricks have been jammed between the bands and the side of the chimney. These extra elements were inserted to increase the width or space between the band and the base of the chimney. Apparently, over time, as these bands weakened, it became recognized that they need to be adjusted to provide attachment and support. The upper band has twisted into loops. This happened as the ribbon of the band bent as the antenna fell downward.
The next picture below shows a wider view angle of this antenna. Interestingly, you can see an additional antenna installed just beyond the chimney in the distance. This type of roof is a modified bitumen roof. Modified bitumen roofs are often used to cover low slope roof frames here in Washington DC. This is a modified bitumen smooth roof membrane and instead of using a granulated ceramic aggregate to protect the membrane from the deleterious effects of exposure to ultraviolet, the roof must be repeatedly painted throughout the life cycle of the membrane.
The next few pictures show satellite dishes. At least one of these dishes is set upon a rooftop sled. The sleds are sized and built to allow the installation of a cementitious paver. The pavers are heavy and the weight of the paver allows it to act like a ballast. A ballast is a weight that keeps something positioned in place. Even with a balast though, because winds can be very heavy on a rooftop, a satellite dish can still move around a bit, especially over time.
As we discussed this past week, a sacrificial slip sheet should be installed underneath all rooftop antenna sleds, to give it separation from the membrane below. We’ve also discussed this issue pretty extensively in a blog article a few weeks back. Even though it’s a very simple type of installation, it’s skipped or missed so often by the actual communications contractors.
Even though communications or satellite dish contractors don’t always follow the rules for rooftop installations, their work on rooftops is prolific. But the picture below shows an example of three satellite dishes and sequence on a rooftop area, here in Washington DC. These several satellite dishes are split between just a few roofs that happened to be one next to the other.
We provide this information here on our blog, and our website, to help our customers and future clients. We recommend every building owner in DC use a contractor like Dupont Roofing DC. We value the longevity of your roof (and your investments) and building. Use a contractor who values the simple and important principles of proper roof construction. Our company specializes in flat roofing here in Washington DC and we’re happy to help building owners of almost all types.
Learn more about our company and the proper techniques of working with roofing on historic buildings in Washington DC here on our blog at DupontRoofingDC.com. You can call us at (202) 840-8698 and email us at dupontroofingdc@gmail.com. We are happy to help and at least talk through options. As you can tell, from even just a relatively quick view through our site, there are many different options. We can try to help look for those options, on the range or spectrum of the timeline for longevity and investment
