Protect Against Rain and Ice with Shielding

Rain and ice shields, also known as ice and water shields, are waterproof membranes used to protect roofs from water and ice damage. Their main purpose is preventing water from getting underneath roofing materials and damaging the roof deck. These shields are required by building code in areas with heavy snow, as they prevent leaks from ice dams.

There are three main types of rain and ice shields: granular/sand surface, smooth surface, and high heat. Each is suitable for different roofing situations. Costs vary depending on type and coverage area. Shields provide extra protection for vulnerable areas like roof valleys, edges, and low-pitch roofs. They should be installed on pitches below 3/12 to prevent water damage.

Where to Install Rain and Ice Shields

Rain and ice shields should be installed in key areas prone to ice buildup and water penetration:

• Roof edges and overhangs where water slides off.
• Valleys where water channels off the roof.
• Around chimneys and skylights to seal flashing.
• The entire roof surface for maximum protection.

Shield Types and Manufacturers

There are several reputable manufacturers of quality rain and ice shields:

• GAF's StormGuard - A smooth surface bitumen membrane.
• CertainTeed's WinterGuard - A polymer-modified asphalt membrane.
• Henry's Blueskin PE200 HT - A high heat-resistant membrane.

Required Installation Areas

Building codes often require shields on the following:

• Eaves up to 24 inches inside the exterior wall.
• Rake edges up to 24 inches inside the side wall.
• Valleys spanning from eave to peak.

Choosing the Right Shield

There are three main types of rain and ice shields to consider:

Self-Adhering Membranes

Self-adhering membranes feature a polymer-modified asphalt coating with a removable plastic backing. They form a waterproof barrier by sticking directly to the roof deck. These are easy to install but can be damaged by high heat.

Modified Bitumen Membranes

Modified bitumen membranes have a fiberglass or polyester reinforcement between layers of flexible SBS-modified asphalt. This type handles high heat better but requires torching or hot mopping to install.

Elastomeric Membranes

Elastomeric membranes like EPDM and TPO form a rubber-like water barrier. They resist heat and ultraviolet light but require special adhesives and may shrink over time.

Proper Installation Process

Surface Preparation

The roof deck surface must be cleaned and primed according to manufacturer specifications to enhance shield adhesion.

Priming

Many types of shields require primer to prepare the surface. Primer increases long-term adhesion and prevents sliding.

Membrane Application

Apply shield horizontally from eave to peak in weather-lap fashion for optimal water shedding. Avoid wrinkles and re-embed as needed.

Seams and Overlaps

Seams and end-laps should have proper overlaps per the product instructions to maintain waterproof integrity.

Flashing

Flash around skylights, chimneys, pipes, and roof joints using manufacturer approved products. This seals gaps.

Maintenance and Inspections

It's important to routinely check and maintain rain and ice shields:

• Inspect for leaks, bubbles, and cracks annually.
• Reapply protective sealants if wear is detected.
• Replace any deteriorated sections as needed.

Installation Mistakes to Avoid

Some common installation errors that compromise protection:

• Inadequate surface cleaning and lack of primer.
• Insufficient overlaps at shield seams & edges.
• Poor adhesion due to trapped moisture or dirt.
• Improper nail placement through the membrane.

Cost Factors and ROI

Typical costs for materials plus professional installation:

• Self-adhering sheets: $2.50-$3.50 per sq/ft
• Modified bitumen rolls: $1.25-$2 per sq/ft
• Labor: $3-$6 per sq/ft

This investment often pays for itself by preventing far more expensive water damage repairs later on.

Determining Needed Materials

To calculate how much shield is required:

1. Measure roof edges, valleys, and other area needing coverage.
2. Account for recommended overlaps at seams.
3. Consult manufacturer area charts to order enough.

DIY vs Hiring a Roofer

Complexity and Safety Concerns

While DIY installation is possible, safety is a top concern. Working on sloped roofs or lifted ladders can pose fall risks. The membrane bonds immediately, allowing no room for error.

Impact on Warranties

Manufacturer warranties often require professional installation. Doing it yourself risks voiding your warranty if problems arise.

Roofer Expertise

Hiring a qualified roofer ensures proper handling, seam sealing, and integration with the rest of the roof system.

Building Code Requirements

International Building Code (IBC)

The IBC requires ice barriers for roof slopes below 6:12 pitch. Shields must extend up from roof edges and valleys.

Regional and Local Codes

Northern climate areas often stipulate shields due to seasonal ice dams and storms. Check municipal requirements.

Alternative Options

Beyond membrane shields, other ice prevention solutions include:

• Heated cables - Melt ice along critical areas.
• Metal strips - Prevent bonds between ice and shingles.
• Protective coatings - Seal and reinforce vulnerable zones.

However, these don't offer the same comprehensive coverage as full rain and ice shield systems.

Frequently Asked Questions

How long do rain and ice shields last?

Properly installed shields have a useful life expectancy of 10-12 years. Harsh weather can accelerate deterioration.

Can shields be installed over old shingles?

No, manufacturers recommend shields only be applied to bare roof decks for full adhesion. Shingles must first be torn off.

Are shields required by building code?

Shield requirements vary locally based on typical weather patterns. Check municipal codes for your region.

Case Study: Hospital Roof Retrofit

A Midwest hospital installed self-adhering ice and water shield across 130 squares of 25 year old shingle roofing to reduce leaks. This provided protection while delaying a full roof replacement.

Rain and ice shields provide an essential roofing system upgrade to protect buildings in climates prone to heavy precipitation and ice storms. Proper installation guidelines must be followed, with special attention given to surface prep, primer use, and seam sealing.

Hiring an experienced professional roofer is recommended for commercial projects and tricky residential installations. Safety and fall risks are also concerns for DIY application. Building codes often mandate shield requirements as well based on typical local weather.

When comparing options, factor in product ratings, composition, warranty coverage, and manufacturer reputation. Overall cost is higher initially but helps avoid extensive water damage over time.