ROOFING GUIDE
Ice Dams: Why They Form and How to Protect Your Roof
An ice dam is a ridge of ice along the roof edge that traps meltwater behind it. That water can back up beneath roofing and into the home. Ice dams are common in Bend, Central Oregon and Northern Utah.
01
How an Ice Dam Forms
Ice dams form when part of the roof is warm enough to melt snow while the edge stays below freezing.
- 1. Snow covers the roof
- 2. Heat from below warms the upper roof deck
- 3. Snow melts and water runs downslope
- 4. Water reaches the cold eave and refreezes
- 5. The ice ridge grows with each cycle
- 6. Meltwater pools behind it and backs up under roofing
02
Why Ice Dams Cause Leaks
Shingles and most roof coverings are designed to shed water running downhill. Water held behind an ice dam can work upward beneath the courses and reach the deck, walls or ceilings.
03
Warning Signs
Large icicles alone are not proof of an ice dam, but they are a sign to look closer.
- Thick ice along eaves and in gutters
- Water stains on ceilings near exterior walls
- Damp or peeling paint on soffits
- Water dripping inside during thaws
- Frost in the attic
04
What Contributes to Ice Dams
Several factors usually work together.
| Factor | Why it matters | Who typically addresses it |
|---|---|---|
| Air leakage into the attic | Warm indoor air heats the roof deck | Insulation / air-sealing contractor |
| Insulation levels | Too little lets heat reach the roof | Insulation contractor |
| Roof ventilation | Airflow helps keep the deck colder | Roofer (DryInside) |
| Ice and water membrane | Protects vulnerable edges and valleys | Roofer (DryInside) |
| Flashing and valleys | Weak details let backed-up water in | Roofer (DryInside) |
| Gutters | Ice can build in and behind gutters | Roofer or gutter contractor |
05
Ventilation and Insulation
Ventilation and insulation work together. Ventilation carries away heat that reaches the attic; insulation and air sealing limit how much heat gets there. DryInside evaluates roof ventilation and will tell you when we observe insulation or air-leakage concerns so you can involve the right specialist.
06
Ice and Water Membrane
A self-adhering ice and water membrane beneath roofing at eaves, valleys and around penetrations adds a layer of protection against backed-up water. Coverage should reflect local code and the roof's exposure.
07
Flashing and Roof Details
Chimneys, skylights, walls and valleys are common entry points when water pools. Sound flashing and properly lapped materials reduce the chance meltwater finds a path in.
08
What to Do If You Have an Ice Dam
If water is entering the home, call us. Avoid chopping ice or using sharp tools, which can damage roofing. Once conditions allow, an inspection can identify what contributed and what damage occurred.
09
Why Bend and Northern Utah See Ice Dams
Central Oregon's snowy winters and sunny days create repeated freeze/thaw cycles. Northern Utah, from Salt Lake City to Ogden and the benches, sees similar cycles with lake-effect and mountain snow. Moab sees ice dams less often, though higher-elevation properties nearby can experience them.
Roofing in BendRoofing in Salt Lake CityOgdenRoofing in Moab
10
Gutters and Ice Dams
Gutters do not cause ice dams, but ice-packed gutters can add weight, pull away from fascia and make the edge ice worse. Clearing debris before winter helps meltwater drain when it can.
11
In Salt Lake City & the Wasatch Front
Bench homes and poorly ventilated attics along the Wasatch Front are prone to ice dams.
12
In Bend & Central Oregon
Sunny winter days and cold nights make ice dams common in Bend and across Central Oregon.
13
Ice Dams in Central Oregon and the Wasatch Front
Repeated freeze/thaw cycles make ice dams a recurring winter issue across Central Oregon and the Wasatch Front.
Roofing in BendCentral Oregon roofingRoofing in Salt Lake CityWasatch Front roofing
COMMON QUESTIONS
Useful Answers Before You Decide
Are icicles the same as ice dams?
Not always. Icicles can form without a dam, but heavy icicles and thick edge ice are worth watching, especially with interior stains.
Will heat cables stop ice dams?
They can help keep drainage paths open in some cases, but they don't address why the roof is warm. We can discuss options during an inspection.
Does a new roof prevent ice dams?
A replacement can add ice and water membrane and improve ventilation, which reduces leak risk. Insulation and air leakage also play a role.
Can ice dam damage be repaired?
Often, yes. Damaged shingles, underlayment, flashing or decking near the eaves can frequently be repaired once the source is understood.
Is ice dam damage a storm claim?
Your insurance carrier determines coverage. DryInside can document the conditions we observe.
Do you offer free roof inspections?
Yes. DryInside offers free roof inspections in Central Oregon, Utah and select Idaho communities.
HELPFUL GUIDES
Read Before You Decide
YOUR HOME. OUR RESPONSIBILITY.
Not Sure What Your Roof Needs?
You do not have to diagnose the problem yourself. Start with a free roof inspection and let DryInside take a closer look.