How to Install Drip Edge and Ice Shield Guide for Eastern Washington Homeowners & Contractors

Why Drip Edge and Ice & Water Shield Matter in Eastern Washington

If you’ve lived through a winter in Spokane, Colville, or Kettle Falls, you already know what our roofs are up against. We get real snow load, hard freezes, and then those classic PNW thaw-and-refreeze cycles that build ice dams along the eaves. Add in bone-dry, hot summers that bake shingles and membranes all season, and you’ve got a roof edge system that has to handle two extremes every single year.

Drip edge and ice & water shield are the unsung heroes at the roof’s edge. Drip edge is the metal flashing that directs water away from your fascia and into the gutter instead of behind it. Ice & water shield is a self-adhering rubberized membrane that seals the deck against water that backs up under shingles when ice dams form. Get the order and coverage wrong, and you’re inviting rot, soffit damage, and interior leaks — often not showing up until years later when the damage is already done.

This guide walks through the correct installation sequence, the products we sell and recommend at our Airway Heights, Colville, and Kettle Falls stores, and the local factors that make Eastern Washington roofs a little different from a roof in Seattle or Boise.

The Correct Installation Sequence — Eaves vs. Rakes

This is where most confusion happens, and honestly, where most roofs go wrong. The order is different at the eaves than it is at the rakes (gable ends), and mixing them up is one of the most common mistakes we see brought back to our counters as a warranty question.

At the Eaves (Bottom Edge of the Roof)

1. Clean, dry roof deck — no leftover debris, no wet sheathing.
2. Drip edge installed first, directly on the deck, with the vertical leg covering the fascia. Pull it back about 3/8″–1/2″ off the fascia face so water doesn’t wick and stain the wood.
3. Ice & water shield goes over the top of the drip edge and extends up onto the deck.
4. Underlayment laps over the top edge of the ice & water shield.
5. Starter strip and shingles follow, overhanging the drip edge by about 1/2″–3/4″.

Fasten drip edge with roofing nails spaced 8–12 inches on center, and overlap adjoining pieces by a minimum of 2 inches. This sequence lets the membrane seal directly to the drip edge and deck, so any water that gets under the shingles during an ice dam event has nowhere to go but back off the roof — not into your fascia or soffit.

At the Rakes (Gable Ends)

Flip the order here. Underlayment and ice & water shield go down first, then drip edge is installed over the top. This protects the underlayment edge from wind-driven rain, which matters a lot on exposed ridgelines around Kettle Falls and the Colville Valley where crosswinds can push moisture sideways under standard drip edge installations.

Why the Sequence Matters

Get this backward — drip edge over the membrane at the eaves, or membrane over drip edge at the rakes — and you create a spot where water can get trapped behind metal or seep under an unsealed underlayment edge. It seems like a small detail, but it’s exactly the kind of thing that causes slow, hidden rot over several winters rather than an obvious leak in year one.

How Far Up the Roof Does Ice & Water Shield Need to Go?

Building code (IRC, adopted with local amendments throughout Eastern Washington) requires ice & water shield to extend from the eave edge to a point at least 24 inches inside the exterior wall line of the structure in regions prone to ice damming — and that’s all of us east of the Cascades.

In practice, most experienced roofers in the Spokane area and up into Stevens County go further than the minimum:

• Standard homes (4:12–6:12 pitch): one to two courses of 36″ membrane, reaching roughly 3–6 feet up from the eave.
• Low-slope roofs (2:12–4:12): extend coverage further, sometimes the full slope, since water moves slower and has more chance to back up under shingles.
• Valleys, dormers, and skylights: full-width membrane through the entire valley and 6″+ up each sidewall or curb, regardless of overall roof pitch.

Homes in Colville and Kettle Falls that sit at higher elevation or in shaded, tree-covered lots tend to hold snow longer into spring, which means longer exposure to freeze-thaw cycling at the eaves. If your property fits that description, it’s worth going a course higher than the code minimum — the material cost difference is small compared to a reroof from water damage.

A Reality Check on Ice Dams

Ice & water shield does not prevent ice dams from forming. What it does is keep the water that backs up behind a dam from finding its way into your attic and walls. If you’re dealing with recurring ice dams, the membrane is your insurance policy, but the actual fix is almost always better attic insulation and ventilation — soffit and ridge vents that keep the underside of your roof deck cold and consistent, so snow melts evenly instead of thawing near the ridge and refreezing at the eave.

Products We Stock and What They’re Good For

We carry a range of drip edge and ice & water shield products at all three of our Eastern Washington locations, and we can help you match the product to your roof pitch, climate exposure, and budget.

Drip Edge Options

• Aluminum drip edge — lightweight, won’t rust, good general-purpose choice for most residential roofs.
• Galvanized steel drip edge — more rigid, holds up well under heavy snow load and repeated ice contact.
• Galvalume drip edge — excellent corrosion resistance, a solid pick if your roof sees a lot of moisture or you’re near irrigated agricultural land where humidity lingers.

Profiles come in standard “L” style for basic eave/rake coverage and “T” style or extended-face profiles for homes with deeper fascia boards — common in older farmhouses and custom builds around Stevens County.

Ice & Water Shield Options

• Standard rubberized asphalt membranes — reliable, cost-effective, good for most eave and valley applications.
• High-temperature rated membranes — worth the upgrade if you’re installing dark-colored shingles that soak up heat during our 90-plus degree Eastern Washington summers. Standard membranes can soften and slide under extreme heat if not rated for it.
• Polymer-modified bitumen membranes — better flexibility in cold temperatures, which matters when you’re installing in October or November before the first hard freeze.

One thing our team always mentions: don’t leave membrane exposed to direct sun for more than the manufacturer’s rated window — usually somewhere between 30 and 90 days. If your project stalls mid-installation (weather delays are common here), get the exposed membrane covered or completed before that window runs out.

Common Mistakes We See Around the Spokane Area

After decades supplying roofing materials across Eastern Washington, we’ve heard about (and helped fix) the same handful of mistakes over and over.

Sequencing Errors

The single biggest issue: drip edge installed over the ice & water shield at the eaves instead of under it. This traps water behind the metal flange instead of letting the membrane seal directly against the deck and drip edge together.

Not Enough Coverage

A single 3-foot course that doesn’t actually reach 24 inches past the interior wall line — this happens more than you’d think, especially on homes with deep eave overhangs where the math doesn’t work out unless you plan for it before you start rolling material.

Skipping Valleys

Valleys are the highest-traffic water paths on your entire roof. Skipping full membrane coverage there — or only running standard underlayment — is asking for a leak during heavy spring runoff.

Poor Nailing Practices

Fastener spacing wider than 12 inches on center, or nails driven too close to the drip edge’s outer nose, weaken the whole assembly and give wind a place to start peeling metal loose. We recommend galvanized roofing nails and consistent spacing — mark your intervals if you’re not used to eyeballing it.

Ignoring Overhang Specs

Shingles should overhang the drip edge by about 1/2″ to 3/4″ — no more, no less. Too little, and water curls back toward the fascia. Too much, and the shingle edge is unsupported and prone to cracking in cold weather, which happens fast once temperatures drop below freezing in a Colville winter.

Treating Membrane as a Cure-All

Ice & water shield helps manage leaks from ice dams, but it won’t stop the dams from forming. If you’ve got chronic ice dam issues, pair your roofing project with an honest look at attic insulation levels and ventilation — it’s usually the more cost-effective long-term fix.

DIY or Call a Pro? What Makes Sense for Your Roof

We sell to plenty of capable DIYers throughout Airway Heights, Colville, and Kettle Falls, and a lot of drip edge and ice & water shield work is within reach for a careful homeowner — but not all of it.

Good DIY Candidates

• Single-story homes with moderate pitch (4:12 to 6:12)
• Simple gable roofs without multiple valleys or dormers
• Localized repairs — replacing a damaged section of drip edge, or re-sealing one problem eave
• Homeowners comfortable with ladder work, fall protection, and following manufacturer install specs closely

When to Bring in a Professional

• Full reroof projects where sequencing errors could void a shingle warranty
• Roofs with multiple valleys, skylights, or dormers requiring detailed membrane work
• Steep-pitch or multi-story homes where safety is a real concern
• Homes with existing ice dam damage or interior leak history — these often need insulation and ventilation work alongside the roofing fix

Local roofing contractors who work Eastern Washington year-round know our freeze-thaw patterns and local code amendments better than an out-of-area crew would, so it’s worth asking about their specific experience with ice-dam climates when you’re getting quotes.

What Drives the Cost of This Project

Drip edge and ice & water shield are usually line items inside a larger reroofing quote rather than standalone projects, but here’s what pushes the price up or down:

• Roof complexity — more valleys, dormers, and penetrations mean more cutting, detailing, and labor hours
• Coverage extent — going beyond code minimum for extra ice-dam protection adds material cost but is cheap insurance
• Product tier — high-temperature-rated membranes and heavier-gauge drip edge cost more upfront but perform better long-term in our climate swings
• Roof height and pitch — steeper, taller roofs require more safety setup, which adds labor time
• Timing — bundling this work into a full reroof is almost always cheaper per linear foot than doing it as an isolated repair later

If you’re gathering quotes, ask your contractor to break out material versus labor costs for the drip edge and membrane specifically — it helps you compare apples to apples between bids.

Get What You Need at Your Local Builders Supply

Whether you’re re-roofing a ranch home outside Airway Heights, patching an eave on a cabin near Kettle Falls, or planning a full tear-off before winter hits Colville, we stock drip edge in aluminum, galvanized steel, and galvalume, along with standard and high-temperature-rated ice & water shield membranes at all three of our Eastern Washington locations. Stop by and talk with our team about your roof’s pitch, exposure, and history — we’ll help you pick the right materials and get the sequencing right the first time. Browse what we carry online at https://bldrsupply.epicor-inet.com/departments, or come see us in person in Airway Heights, Colville, or Kettle Falls.

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