Rough Winter Has Been Hard on Roofs


If you’re like me, you’re still cleaning up from one of the roughest winters in memory, particularly here in the Northeast. Not only did landscaping and trees take the brunt of record snowfall, but the outsides of our homes took a beating as well, wreaking havoc on roofs.

Why am I talking about snow and ice during the spring? This is one of the biggest home improvement times of the year and chances are a number of roofs will need to either be repaired or replaced due to ice dams.

As a result of the constant freezing and thawing many roofs were subjected to ice dams. Ice dams are formed when heat from the inside of a home escapes into the attic and warms the roof decking during the winter. This heat, combined with heat from the sun, can melt snow on the roof. Melting snow then runs down toward the eaves as water. When it reaches the cold eaves and gutters it refreezes. This continual thaw and re-freeze process creates ice dams. The result is water can back up under the roof shingles where it can soak through the roof decking or wall sheathing, causing damage to attics, ceilings and walls. Ice dams make for some incredible icicles off the gutters, but the damage can be severe.

There are three ways to defend against the damage ice dams cause:

Attic Insulation – Insulation keeps heat from escaping from your home’s living space into your attic. You can add insulation batts or blown-in insulation to improve attic insulation. If the home was built before 1980 chances are that more attic insulation is needed.

• Attic Ventilation System – Unchecked moisture can promote mold, mildew, and wood rot. Natural or static ventilation systems consist of simple vent or covered openings in your attic. These are typically ridge vents, gable, eave, or roof vents. Many ventilation experts agree that externally baffled ridge vents combined with vented soffits are a very effective method for ventilating an attic.

Water-proofing shingle underlayment – This is only an option if the roof needs to be replaced. While water-proofing underlayment does not prevent the formation of ice dams, it will prevent backed up water from getting into the house in those roof areas where it is applied.

Making changes to prevent the occurrence of ice dams is critical for the health of the home and its energy efficiency. An unprotected roof is an ice dam crisis waiting to happen.


  1. Sorry for the delay in getting back to you. CertainTeed does warrant that water will not penetrate our WinterGuard underlayment even through the nail holes:
    CertainTeed warrants to the consumer that its WinterGuard Sand, WinterGuard Granular
    and WinterGuard HT Waterproofing underlayments, when applied beneath a new shingle,
    slate or tile roof application, or re-roof application and when applied to a clean
    roof deck*, will be free from manufacturing defects and will remain watertight with
    respect to that area only over which it is applied for the period of the written warranty
    applicable to the roofing material applied over the WinterGuard up to a maximum of 50
    (fifty) years.

  2. Michael J Lovely on

    I have to partially disagree, mostly with the waterproofing underlay. If any underlay were waterproof, we’d leave the shingles at the store. You nail through shingles you get holes in underlay. Underlay is more an insulator and provides protection to the decking from underneath the shingle.

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