text: If your roof is in shambles or falling apart, you may choose to add a second layer over the existing shingles to save money. Although there's nothing wrong with reroofing your home, it may cause more problems for you in the future, including telegraphing. Learn more about telegraphing and how replacing your entire roof can prevent it below.
  Roofs can undergo numerous changes over the years. Some of these issues don't become apparent until you place a second layer of shingles on your roof, including telegraphing. Telegraphing can make the surface of your roof appear unkempt, lopsided, or even bumpy.
  Old shingles, underlayment, and other structures on the roof can experience a number of issues over time, including bubbling, lifting, and rippling. Some of the defects can be difficult to see, even in direct sunlight. But once you place new shingles over the old shingles, the defects can become apparent. The defects essentially telegraph, or imprint, on the new shingles.
  You want to have a roofer strip or remove all of the existing shingles, underlayment, and other structures from the surface of your roof. A roofer can examine the surface of your roof's deck for any imperfections that may telegraph on your new roof later. If a contractor finds broken nails, pieces of decayed wood, or anything else on a bare surface, they can remove them.
  A contractor can now add a new underlayment or membrane to the cleaned roof deck. A roofer may need to smooth out the membrane thoroughly before they cover it with shingles. Defects can develop in the membrane if it contains tears and wrinkles. The defects may telegraph into your new shingles later.
  After a contractor secures the membrane, they'll begin the shingle installation process. You want to allow a roofer plenty of time to lay down the new shingles. A contractor must ensure each shingle lays flat against the membrane. If the shingles don't lay flat against the membrane, they can curl or bend later on. Rain can soak into the damaged shingles and damage your roof.
  The entire installation time can vary, depending on the size of your roof and home. The condition of the roof deck can also affect the installation time. If you have concerns regarding the installation time, consult a roofer right away.