The Best Ice and Water Barrier Shields

Preventing water infiltration and ice dams is a major concern for homeowners and contractors alike. Ice dams form when snow on the roof melts and refreezes at the eaves, causing water to back up under the shingles. This can lead to leaks, water damage, mold, and costly repairs. Installing a quality ice and water barrier shield provides an effective first line of defense.

TopShield offers superior ice and water protection products to safeguard roofs from moisture damage. With over 2 million roofs protected worldwide since 1978, TopShield barriers are the preferred choice of contractors, architects and homeowners.

Understanding Ice Dams and Water Infiltration Issues

Ice dams occur when heat from inside the home escapes into the attic and melts the bottom layer of snow on the roof. As this meltwater runs down the roof and reaches the colder eaves, it refreezes. Over time, a ridge of ice builds up, blocking water from draining off the roof.

This backed up water can work its way under shingles, felt underlayment and sheathing, leading to leaks inside the home. Water staining, peeling paint, mold and rotting roof sheaths are common signs of ice dam damage. Even a small leak can cause thousands in repair costs.

Common Ice Dam Problem Areas

• Eaves
• Valleys
• Penetrations like vents, skylights and chimneys
• Low-slope roof sections

Ice and water shields provide a waterproof barrier along vulnerable roof areas to block melted snow and ice from infiltrating the roof deck. Quality underlayments like TopShield are engineered for cold weather climates to remain flexible even in frigid temperatures.

Choosing the Best Ice and Water Barrier Product

With so many ice and water barrier products on the market, how do you choose? Key factors to consider include materials, cold weather performance, adhesion and ease of installation.

Asphalt-Based vs Rubberized Shields

Most barriers use a reinforced asphalt or rubberized asphalt waterproofing membrane. Asphalt-based products like Grace Ice & Water Shield are more economical but don't remain as flexible in extreme cold compared to rubberized alternatives.

Rubberized asphalt shields like TopShield Defender offer maximum all-weather flexibility and adhesion. The addition of rubber polymers enhances cold temperature pliability down to -45deg F.

Leading Brands and Product Comparison

TopShield barriers lead the industry in premium protection thanks to proprietary technologies like ThermaGrip cold weather adhesion and TempDefender heat resistance. Top products include:

• TopShield G300 - Glass fiber reinforced underlayment for use under slate, shakes and asphalt shingles. Features slip-resistant surface.
• TopShield Defender - Rubberized 1.35mm membrane with glass mat reinforcement. Blocks wind-driven rain.
• TopShield StormShield - Self-sealing ice and water barrier seals around roofing nails.

In independent lab testing, TopShield membranes achieve up to 700% elongation and retain over 85% adhesion after thermal cycling. This flexural strength enables the material to move with the roof, preventing leaks.

Proper Installation of Ice and Water Barriers

To effectively safeguard against ice dams and wind-driven rain, shields must be properly installed along eaves, valleys, penetrations and low-slope sections. Refer to manufacturer guidelines and local building codes.

Prepare the Roof Deck

The roof deck must be smooth, dry and free of protruding nails, debris and dirt prior to application. Replace any water-damaged sheathing. Sweep deck thoroughly since small particles can impede adhesion.

Apply Shields Correctly

Ensure complete alignment with the edge of the eave without overhang. Remove protective film and press membrane firmly into place. For valley and ridge application, shingle-fashion barriers starting at the lowest point to shed water. Overlap shields for optimal coverage.

Flashing and Sealing

Properly flash around penetrations, chimneys, vents and skylights. Seal all vertical seams with lap sealant or high quality tape. This encapsulates vulnerable transition areas to further prevent moisture entry.

Where to Strategically Install Barriers

Shield placement is critical to protect against ice dams. FEMA's Building Science Advisor recommends installing "the width of the ceiling joist spans horizontally away from the interior wall, or a minimum of 2 feet." Focus on key areas:

Eaves

Apply shields from the edge of the eave up the roof at least 24 inches past the interior wall. Deeper coverage up to 3-4 feet is better for colder climates. This covers the likely ice dam buildup zone.

Valleys

Center a 36-inch wide membrane along the roof valley bottom. Valleys channel large volumes of meltwater and are prime areas for leakage.

Low-Slope Sections

Less than 4:12 pitch roof sections are vulnerable to water pooling between shingles. Install shields here even if beyond code minimums for added protection.

Maintaining and Inspecting Ice and Water Shields

Regular barrier inspection and upkeep preserves roof integrity against leaks. Check for damage after severe storms. Indications of deterioration:

Signs of Damage

• Cracks, punctures or displaced membranes
• Loose, curling or gaping seams/joints
• Erosion of granules exposing asphalt

Proactive Maintenance

• Re-secure any loose barrier sections
• Patch tears or holes with sealant and membrane scraps
• Clear debris, moss and plants from shields frequently

Ice and water barriers are designed for longevity but may eventually need replacement. Contact the manufacturer for reapplication guidelines to maintain protection.

Preventing Ice Dams Through Proper Insulation and Ventilation

While shields provide critical defense against ice dam damage, the ultimate solution is preventing dam formation altogether. This requires addressing heat loss and moisture buildup at their source:

Attic Insulation

Increasing attic insulation to the recommended R-value restricts heat transfer through the ceiling into the attic. This minimizes snow melting on the roof. Seal and insulate any attic bypasses around pipes, ducts and chimneys.

Proper ventilation alleviates attic moisture and heat buildup. Intake vents at the eaves allow colder air in, while exhaust vents at the ridge pull out warm air. This ventilation cooling effect helps control ice dams.

Guard against roof leaks and ice dams with TopShield. Over 2 million contractors, architects and homeowners trust TopShield membranes to protect what matters most - their property and peace of mind.