This time of year, we start receiving panicked emergency calls for leaky roofs that failed during the tough winter season. Most roofs fail long before their anticipated lifespan and not just because of their age.
Main reason? Improper attic insulation or ventilation prevents the continuous airflow of outside air into the attic. When ventilation is done right, there is a continuous airflow up through the soffits continuing through the ridge or mechanical vents. This helps during the warm summer months when attic temperatures can reach well over 130 degrees, as well as during the winter during that horrible "ice dam" building season.
The goal is to balance the airflow and temperature protecting the valuable living areas below. A good rule of thumb is one square foot of attic ventilation for every 300 s.f. of attic space. IE: If your attic is 1200 s.f., you'll need a total of 4 s.f. of ventilation split equallywith 2 feet in the soffit/eave and 2 feet out the ridge or mechanical vents. This will ensure good airflow through the attic.
We all know of those dreaded ice dams ! Having the right amount of insulation keeps the heat where it should be, in your living area! When you do not have proper insulation, it allows the warm living space air below to rise making the attic warmer. The result is melting snow turns into water, water then runs toward the eave where it re-freezes creating ice dams. Water then builds up under the shingles and you know the rest of the story – wet ceilings, walls- a total mess.
We've seen all sorts of problems including mold, mildew growth, plywood deflection, curved shingles, wood rot, frame rot, etc.
Short term, the easiest way to keep your heating/cooling bills down and minimize your likelihood of an ice dam is to have proper insulation and attic ventilation. Long term, you'll be extending the lifespan of your roof and preventing expensive repairs.