For most Northeast Ohio homes, synthetic underlayment is the stronger choice over traditional felt: it is lighter, resists tearing, and sheds moisture far better through a long Lake County winter. That said, the synthetic underlayment vs felt decision is not the full picture, because Ohio’s residential code requires a separate ice and water shield along your eaves no matter which base layer you pick. Roof underlayment is the water-resistant layer installed directly on your roof deck, beneath the shingles, and it is the last line of defense when wind-driven rain or melting snow slips past the surface.
In the snowbelt east of Cleveland, where ice dams and lake-effect snow are a yearly reality, that hidden layer does a lot of quiet work. This guide breaks down how felt and synthetic underlayment compare on durability, cost, and winter performance, what Ohio’s building code actually requires, and how to choose the right system for your Mentor-area home.
Key Takeaways
Here are the most important points before we get into the detail:
- Synthetic underlayment generally outperforms felt on durability, weight, and water resistance, which matters in Northeast Ohio’s freeze-thaw climate.
- Asphalt-saturated felt (the classic #15 or #30 “tar paper”) still works and costs less upfront, but it can wrinkle, tear in wind, and absorb water over time.
- Ohio’s Residential Code requires an ice barrier, commonly called ice and water shield, extending at least 24 inches inside the exterior wall line at the eaves, regardless of which underlayment you choose.
- The right choice depends on your roof’s slope, your budget, and the crew installing it, so the contractor matters as much as the material.
What Is Roof Underlayment, and Why Does It Matter in Northeast Ohio?
Roof underlayment is the protective sheet that goes down on the wood roof deck before the shingles are nailed on. Shingles are the first barrier against the weather, but they are not watertight on their own. When rain is driven sideways by wind or when snow melts and refreezes at the eaves, water can work its way under the shingles, and the underlayment is what keeps that moisture off the deck and out of your attic.
That job is harder here than almost anywhere else in the state. Chardon averages roughly 113.7 inches of snow a year, compared to about 70 inches in Cleveland, because northwest winds cross Lake Erie, pick up moisture, and dump it right over Geauga and Lake counties (Current Results, from NWS data). All of that snow sits, melts, and refreezes on local roofs for months at a time.
Because of that, underlayment quality is not a minor line item for homeowners here. It is a core part of a durable roof system, which is why a quality base layer is built into every professional residential roofing installation in Chardon and the surrounding snowbelt communities.
Synthetic Underlayment vs. Felt: How Do They Actually Compare?
When you compare synthetic underlayment vs felt head to head, synthetic wins on most measures that matter in a harsh climate, while felt holds a small edge on upfront price. Here is how the two materials stack up on the factors that affect how long your roof lasts.
Durability and tear resistance. Felt is a paper or fiberglass mat saturated in asphalt. It is relatively brittle and can tear during installation or lift and flap in high wind before the shingles go on. Synthetic roofing underlayment is made from woven polypropylene or polyester, so it is far tougher and stays put even when a job runs across a windy Lake County afternoon.
Water resistance. Felt absorbs water and can wrinkle or buckle when it gets wet, which creates uneven spots under the shingles. Synthetic sheds water and does not absorb it, so it keeps protecting the deck even if the roof is left dried-in for a few days between tear-off and shingle installation.
Weight and safety. A roll of synthetic covers far more area than a roll of felt at a fraction of the weight, and most synthetics have a textured, slip-resistant surface that gives crews better footing on steep or frosty roofs.
Cost. Felt is cheaper per square, and for a tight budget it is still a code-compliant option. Synthetic costs more up front but tends to pay off over the life of a roof through fewer leaks and a cleaner, flatter shingle surface.
Do Northeast Ohio Homes Need Ice and Water Shield?
Yes. In this region, an ice barrier is not optional, and it is separate from your main underlayment choice. The Residential Code of Ohio requires an ice barrier in areas with a history of ice forming along the eaves, which includes all of Lake County and the surrounding snowbelt.
Under Section R905.1.2, that barrier must run from the lowest edge of the roof to a point at least 24 inches inside the exterior wall line of the home, and it has to be either two cemented layers of underlayment or a self-adhering polymer-modified bitumen membrane, the product most homeowners know as ice and water shield (2019 Residential Code of Ohio, Chapter 9). On steeper roofs, the coverage requirement extends even further up the slope.
This is the single most important detail for ice dam protection in Northeast Ohio. When snow melts higher up a warm roof and refreezes at the cold eaves, water backs up behind the ice and can push under standard shingles and felt. A self-adhering ice and water shield seals around every nail and stops that backup from reaching the deck. Any reputable residential roof replacement in this area should include this membrane at the eaves, in the valleys, and around penetrations such as chimneys and skylights.
How Is Roof Underlayment Installed During a Roof Replacement?
Underlayment is installed in a specific order, and the sequence matters as much as the materials. During a professional residential roof installation, a quality crew generally follows these steps:
- Tear off and inspect the deck. The old roof comes off down to the wood, and the crew checks for soft, rotted, or water-stained sheathing that needs replacing before anything else goes down.
- Apply the ice and water shield. The self-adhering membrane is laid first along the eaves (past the 24-inch code line), in the valleys, and around chimneys, vents, and skylights.
- Roll out the field underlayment. Synthetic underlayment or felt is installed across the rest of the deck, overlapping each course and running up and over the ridge for full coverage.
- Add drip edge and flashing. Metal drip edge and new flashing tie the layers together at the edges and transitions so water is directed off the roof, not into it.
- Install the shingles. With the deck fully protected, the shingles go on as the finished, visible weather surface.
Skipping or rushing any of these steps, especially the ice and water shield, is where many premature leaks in older local roofs begin.
How Do You Choose the Right Underlayment for Your Lake County Roof?
For most homes in Northeast Ohio, synthetic underlayment paired with a code-compliant ice and water shield is the system that holds up best against lake-effect snow and freeze-thaw cycles. Felt remains a legitimate budget option on a simpler roof, but the heavier the snow load and the more valleys and penetrations your roof has, the more a synthetic system earns its cost.
The bigger factor is who installs it. The best underlayment in the world will still fail if it is lapped the wrong way, nailed carelessly, or stopped short of the code line at the eaves. That is why it pays to hire a contractor who documents the roof system they are putting on your home.
As a GAF Master Elite certified company, Raw Roofing Solutions installs manufacturer-approved underlayment and ice barrier systems and backs the workmanship with a lifetime warranty. Every project starts with a 19-point roof inspection with photo documentation, so you can see the condition of your deck and understand exactly which layers are going on before work begins. That same standard applies whether you are in Mentor, Chardon, or booking a residential roofing installation in Painesville.
Frequently Asked Questions About Roof Underlayment in Northeast Ohio
These are the questions Lake County homeowners ask most often about underlayment and ice barriers.
Is synthetic underlayment better than felt for a roof?
For most Northeast Ohio roofs, yes. Synthetic underlayment is lighter, more tear-resistant, and does not absorb water the way felt can, so it protects the deck more reliably through heavy snow and freeze-thaw cycles. Felt still costs less up front and remains code-compliant, so it can be a reasonable budget choice on a simpler, lower-slope roof.
How long does roof underlayment last?
Underlayment is designed to last as long as the roof covering above it, which for quality asphalt shingles in this climate is typically 25 to 30 years or more. Synthetic underlayment generally tolerates heat, cold, and moisture longer than felt. The real lifespan depends on install quality, attic ventilation, and how well the roof sheds snow and water.
Is ice and water shield required by code in Ohio?
Yes. The Residential Code of Ohio requires an ice barrier at the eaves in regions with a history of ice forming along the roof edge, which covers Lake County and the broader Cleveland snowbelt. The barrier must extend at least 24 inches inside the exterior wall line and be a self-adhering membrane or two cemented layers of underlayment.
Can you install new underlayment without replacing the whole roof?
Not usually. Underlayment sits directly under the shingles, so reaching it means removing the roof covering above it. In practice, new underlayment goes down as part of a full roof replacement or a large section tear-off. If only a small area is damaged, a targeted repair may be possible, which a professional inspection can confirm.
Does synthetic underlayment prevent ice dams?
Synthetic underlayment helps, but the ice and water shield membrane is what actually protects against ice dam leaks. The self-adhering membrane seals around nails at the eaves and valleys where ice dams form, stopping backed-up water from reaching the deck. Good attic insulation and ventilation reduce ice dams in the first place, so the two work together.
Protect Your Roof Before Winter
If you are planning a new roof or want to know whether your current underlayment and ice barrier are up to a Northeast Ohio winter, schedule your free 19-point roof inspection with Raw Roofing Solutions today.