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Improper Attic Ventilation

Improper Attic Ventilation

June 4, 2019

Poor or improper attic ventilation is one of the most common reasons for premature roof failure because it can cause excess heat build up in your attic. This heat warms and dries out the shingles from their underside, which eventually leads to loose granulos (this is what protects the shingles from the sun’s UV rays). In turn, this causes the shingles to lose their shape and their protective oils, resulting in leakage or excess shingle buckling.

In the winter, moisture can build in your attic, which then leads to mould and wood rot.  A good attic ventilation system has well balanced airflow between intake and exhaust, properly sealed bypasses and penetrations, and the correct amount of insulation.

Excess Moisture and Condensation in Your Attic

Poorly ventilated dishwashers, washing machines, dryers, and bathroom exhaust fans are among the top culprits of moisture buildup in your attic. This excess moisture enters through penetrations and bypasses that travel through the attic including plumbing stacks, pot lights, electrical wires, and attic hatches.

Attic Ventilation Errors

A few of the most common errors made in attic ventilation systems include:

  • Improper bathroom fan venting (i.e. running it directly into the attic)
  • Too much insulation, which as a result, blocks intake vents
  • Removal of wood soffit or the addition of aluminum soffit panels that do not have enough venting holes
  • Installation of two different types of exhaust vents in the same attic, which in turn, short circuits the system
  • Installation of an unequal number of intake and exhaust vents which results in an unbalanced ventilation system
  • Incorrect calculation or lack of knowledge in terms of what the correct amount of venting is for a particular home

What to Look Out For

Take a precautionary approach to the care of your roofing system and keep your eyes open for key occurrences that indicate an attic ventilation problem:

attic ventilation problem Improper Attic Ventilation
  • Snow that is melting unevenly
  • Icicles that form around the edge of your roof
  • Rusty nails
  • Insulation that is wet or compressed
  • Curled or cracked shingles
  • Mould or mildew inside your attic
  • Rust spots on your attic insulation
  • Attic roof boards or plywood that is black or that has black spots

Integrity Roofers evaluates your attic ventilation problem and recommends the most ideal, cost effective, long lasting solution for your home.

Contact us today to book a complimentary assessment.

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