Want to Prevent Ice Dams? A Rain Shield Keeps You Covered
Few things are more frustrating than discovering leaks and water damage on your ceilings and walls. The culprit? Ice dams. Those thick chunks of ice can form along your roof's edges, trapping melting water from snow. The water often backs up under shingles and into the attic. The result is costly repairs, mold growth, and even collapsed ceilings.
Luckily, you can fight back against ice dams with an important line of defense - a rain and ice shield.
What Are Ice Dams and Why Do They Form?
Ice dams are ridges of ice that build up along the eaves and edges of a roof. As snow on the roof starts to melt during winter thaws, the water runs down and refreezes when it reaches those overhanging edges.
The ice ridge grows larger over time as melting water continues flowing down to the colder roof edges. This forces the water to back up, sometimes under roof shingles. The water can trickle through tiny cracks and openings, eventually dripping inside your attic and walls.
Where and How Ice Dams Form
Ice dams are most common in areas with heavy winter snowfall. They tend to form after periods of thawing when daytime temperatures rise above freezing.
As attic heat escapes through the roof, it warms the snow along the upper roofline. This top layer melts first while snow farther down remains frozen. Meltwater runs down the slope and refreezes when it reaches the colder eaves.
Variables like poor insulation, roof pitch, and ventilation patterns impact where and how readily ice dams form. For example, lower pitch roofs allow more snow accumulation, increasing meltwater runoff.
The Damage Ice Dams Cause
Pools of trapped water can leak through your shingles, rafters, and sheathing. Drywall, insulation, and wood become soaked. This leads to:
- Ceiling stains, peeling paint, and collapsed drywall
- Wood rot, mold growth, and compromised structural integrity
- High heating bills from heat loss
- Dripping and electrical hazards from water around lights and wires
In addition to repairs, you'll deal with unhealthy humidity and foul mildew odors inside your home. The destruction worsens over time without prevention measures.
Understanding Rain and Ice Shields
A rain and ice shield provides a vital, waterproof barrier along your roof's most vulnerable lower edges and valleys. It adheres securely to the roof decking, acting as an underlayment beneath your shingles.
What Is a Rain and Ice Shield?
This roofing membrane is a sturdy, reinforced material designed to stick fast and shield critical areas. Special compounds make it self-sealing around nails, resistant to high winds, and impenetrable to water.
Unlike standard roofing felt, it contains a rubberized asphalt or modified bitumen that provides an extra-strong, bonded seal. Some even include an adhesive underside for easy attachment.
How a Rain Shield Prevents Leaks and Ice Dams
Applied along eaves, valleys, and protrusions like chimneys, a rain shield guides water safely down your roof. Its waterproof adhesive seal keeps moisture from backing up and seeping through.
The barrier also prevents meltwater from refreezing into damaging ice dams. Any water pools up harmlessly on top of the shield instead.
Areas Where a Rain Shield Should Be Installed
Focus application along the roof areas most prone to ice dams and wind-driven rain:
- Eaves - The overhanging edges where ice dams start
- Valleys - The internal roof angles where water collects
- Rake edges - The angled roof edges along gables
- Dormers, skylights, and chimneys - Any projections interrupting water flow
For roofs with lower pitch, consider running the shield from eave to ridge for full coverage.
Benefits of Rain and Ice Shield Underlayment
- Prevents leaks, water damage, and ice dam formation
- Saves on emergency repairs, drywall replacement, and mold remediation
- Sustains insulation effectiveness and avoids heat loss
- Prolongs the roof's structure and shingle lifespan
- Provides peace of mind during heavy storms and freezing weather
Selecting the Right Rain Barrier Product
With proven materials like reinforced polymer and rubberized asphalt available, you want the optimal ice and water protection.
Self-Adhering Modified Bitumen Sheets
These heavy-duty sheets consist of a fiberglass or polyester mat coated in rubberized asphalt. The adhesive underside bonds tightly to the roof deck for a highly secure barrier.
Rubberized Asphalt Membranes
Liquid asphalt has polymer modifiers added to make an elastic, waterproof membrane. These affordable rolls apply quickly but lack the adhesion of stickier barriers.
Liquid-Applied Ice Dam Membranes
A liquid waterproofing compound gets painted or sprayed onto the roof. Though requiring skill to apply, it conforms well to surfaces and penetrations.
What to Look for When Choosing a Product
- Class A fire rating for fire safety
- At least 60 mils thickness for durability
- Sealant strip for watertight sheet seams
- Resistance to high winds and temperatures
- Compatibility with your roofing material
Your contractor can suggest the right product for your situation, climate, and budget.
Proper Installation Techniques
Improper installation jeopardizes your shield's ability to protect against leaks and ice dams. Follow best practices.
Required Tools and Materials
Before starting, assemble all necessary tools and gear:
- Utility knife
- Tin snips
- Measuring tape
- Felt roller
- Caulk gun
- Roofing hammer
- Safety equipment - harness, ropes, boots
Have your rain barrier rolls or sheets staged nearby. Ensure adequate overlap materials.
Safety Considerations
Exercise caution working on roofs to prevent falls. Observe the following precautions:
- Restricted access areas below roof
- Body harness with secured ropes
- Sure footing with slip resistant shoes
- No tools or materials left unattended aloft
- No work on wet or windy days
Take care when handling membranes to avoid tripping hazards or tool punctures.
Step-by-Step Installation Guide
Follow manufacturer specifications for full watertight performance:
- Clean roof deck thoroughly removing any debris
- Apply adhesive primer if required
- Roll barrier from eaves up, overlapping edges 6 inches
- Embed barrier into adhesive, smoothing out any air pockets
- Seal seams and terminations with provided tape
- Secure to deck around protrusions with proper nails
- Inspect for fishmouths, gaps, or bubbles then correct
- Install metal drip edge over membrane at eaves
It is essential to keep the membrane continuous and avoid unsealed seams or tears.
Ensuring Full Coverage Along Vulnerable Areas
Make certain to run the rain shield up walls and sufficiently past ice dam prone areas. Extend it:
- 2-3 feet past the interior walls' exterior plane
- At least 24 inches horizontally from the roof interior's warm boundary
- Up and over gable end rake edges
This helps the rain barrier provide protection against both downward roof leaks and melt backup.
Checking for Proper Adhesion
To confirm your rain shield adhered correctly:
- Press down firmly and verify full contact without bubbles
- Ensure membrane lies completely flat without lifted edges
- Test peel resistance to confirm watertight bond
Promptly seal any fishmouths or spots showing improper adhesion.
Added Protection Against Ice Dams
For comprehensive ice dam defense, pair your rain shield with these added measures:
Heating Cables to Melt Ice
Heating cables or heat tape applied along the eaves helps melt existing ice dams. This stops water from working under the shingles. The cables can prevent new ice buildup as well.
Removal Tools for Snow and Ice
Use snow rakes and ice chisels to clear built-up snow and ice from your roof safely. Focus on thin, overhanging areas where dams start. But avoid damaging your shingles or shield.
Attic Insulation to Prevent Heat Loss
Better insulation slows the heat loss that warms your roof and melts the snow. This reduces ice dam formation. Caulk and weatherstrip any attic cracks too.
Roof Ventilation Improvements
Increasing ventilation helps control attic humidity and prevents condensation that can soak roof boards and insulation.
When to Call a Professional Roofer
While handy homeowners can install their rain barrier, professional roofing contractors provide experience and best practices.
Signs You Need a Roof Inspection
Consider hiring a roofer if you notice:- Visible damage like missing or warped shingles
- Leaks, stains, or sagging areas indoors
- Mold, dampness, or odor in the attic
- Excess roof ice or areas prone to ice dams
A qualified roofer can evaluate trouble spots and recommend solutions like improved attic ventilation.
Benefits of Hiring a Professional Roofer
Pro roofer advantages include:- Access to required roofing tools, equipment, and safety gear
- Ability to identify issues like inadequate insulation or decay
- Knowledge to diagnose and correct any roof leaks or flows
- Training on proper membrane installation methods
- Resources to obtain all necessary rain shield products
Their expertise in both products and processes produces superior results.
Questions to Ask Potential Roofing Contractors
- Are you licensed and insured to perform roof work?
- Can you provide references from past rain barrier jobs?
- Do you offer a workmanship warranty?
- Will you handle securing any necessary permits?
- How long have you been installing these roofing products?
Verify they employ qualified technicians and follow good safety practices.
Typical Costs for Professional Installation
Average costs fall in the range of:
- $3 - $8 per square foot for materials
- $150 - $400 per square for labor and installation
Total costs for an average home are $650 - $1600, but can go higher for large or complex roofs. Get quotes from multiple contractors.
Maintaining Your Rain and Ice Shield
Like all building materials, rain shields require some periodic maintenance and care for optimal longevity.
Inspecting Your Shield Annually
Make roof inspections part of your yearly home maintenance routine. Check for:
- Damage from storms, falling branches, or foot traffic
- Wind uplift or loose membrane sections
- Exposed adhesive indicating loss of granules
- Cracks, bubbles, gaps, or erosion
Use binoculars to scan hard to reach areas closely. Inspect sealants around roof joints and projections.
Identifying and Repairing Gaps or Tears
Seal any tears, holes from fasteners, or openings along seams right away with roofing cement or self-sealing tape. Reinforce deteriorated areas.
Watch for sections peeling from loss of adhesion and re-secure or replace them. Stopping minor damage early prevents major roof problems down the road.
Replacing Deteriorated Sections
Plan to replace any damaged, loose, or overly worn sections. Use compatible membrane material and lap new patches under old sheets. This maintains waterproof integrity.
Always replace the rain barrier when installing a new roof or recovering an existing roof. The shield protects your investment.
Preventative Maintenance Best Practices
Help your rain shield last by:
- Cleaning debris like leaves from the roof and gutters
- Avoiding unnecessary foot traffic over the membrane
- Keeping nearby trees trimmed back from the roof
- Re-inspecting after severe weather
Take steps to improve attic insulation, ventilation, and airflow as well. This helps reduce ice dams.
Don't dread the freezing, thawing, and leakage cycle another winter. Take control by installing a rain and ice shield.
Rest easy knowing your roof is protected from hazardous ice dams and expensive water damage even during heavy snows. Your valuables remain safe from attic leaks.
Defend your biggest investment - your home. With an expertly installed rain barrier in place, you can finally stop stressing about the roof and just enjoy the beauty of freshly fallen snow.