Many types of buildings can block reception because of the materials used to construct your home/condo/apartment. 

  1. Stucco and Concrete:  Since metal mesh or metal rebar is used in these two construction types for an antenna to work effectively it must either be placed in a window facing the direction of the towers or a roof antenna is needed to get the antenna up and over the blockage.  Metals act as a barrier that in essence cages the signals and bounces them around making it almost impossible for the signals to "land" on the antenna.
  2. Mobile homes/Aluminum Siding:  Again metals reflect and bounce signals.  A roof mounted antenna or indoor antenna on the window facing the towers is the only option for this type of home.  Vinyl siding is OK. 
  3. Metal Roofs:  The only option for homes with a metal roof is to mount the antenna up and over the roof line so that the signals are not bounced away from the antenna.
  4. Radiant Barriers, Foil lined conduits/duct work, Foil Heat Shields, Solar Panels:  All of these things will effectively block signals so if these are present in your attic a roof mounted antenna would be necessary.

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