Key Takeaways
An ice dam is not a weather problem. It is a heat problem, and it is caused by your attic rather than by the storm.
Redmond sits in the high desert with sub freezing winter nights and warm bright days, and that daily swing is the exact cycle that builds ice at an eave.
Lower pitch roofs hold meltwater longer and are the most common place ice dams form in Redmond and Bend.
The fixes are almost all done from inside and above the ceiling: air sealing, insulation depth, and balanced soffit and ridge ventilation. Heat cable is a symptom treatment, not a repair.
HOMEMASTERS Bend serves Redmond, Terrebonne, Tumalo, Sisters and Powell Butte. Free written estimates. Call (541) 527-7002.
Get an assessment from HOMEMASTERS Bend, Oregon CCB# 243370, Owens Corning Platinum Preferred, CertainTeed ShingleMaster and GAF certified, with W-2 employee crews rather than subcontractors. Call (541) 527-7002.
If you have ever watched a thick ridge of ice build along the edge of your roof in January and assumed it was simply what winter does here, this is the useful correction: your neighbor with the same weather and no ice ridge does not have better luck. They have a colder attic.
That is the whole mechanism, and once you see it the fix becomes obvious. It also explains why the work has to happen now rather than in December.
What causes ice dams on a Redmond roof?
An ice dam forms when heat escaping from the living space warms the roof deck, melting snow on the upper part of the roof. That meltwater runs down until it reaches the eave, which overhangs unheated space and stays at outside temperature. There it refreezes. Repeat the cycle and the ice ridge grows, backing water up under the shingle courses where it can enter the deck and the ceiling below.
Why Central Oregon builds ice dams so efficiently
Three local conditions combine here, and Redmond has all three.
The temperature swing is large. High desert winters bring sub freezing nights followed by bright days with intense high altitude sunshine. That is a melt and refreeze cycle every twenty four hours rather than an occasional event, and each cycle adds to the ice at the eave.
Pitch is often shallow. A good deal of Redmond housing stock, particularly mid century ranch homes, carries lower pitch roofs. Water leaves a shallow roof slowly, which means more of it is still on the roof when the temperature drops in the afternoon. Steeper roofs in Sisters and the higher elevations shed faster and dam less, even though they see more snow.
Snow load holds the meltwater in place. Ground snow loads in this area run 25 to 35 pounds per square foot depending on location, and a snow blanket acts as insulation, keeping the deck beneath it warmer than the eave and feeding the cycle.
The four fixes, in the order they matter
1. Stop the heat leaving the ceiling
This is the actual repair and it is the one people skip. Warm air escapes into the attic through recessed light housings, bath fan penetrations, the gap around a chimney chase, top plates of interior walls and the attic hatch. Sealing those is unglamorous work, it costs far less than roofing, and it addresses the cause rather than the symptom.
2. Get the insulation depth and coverage right
Insulation slows what air sealing does not stop. The common failure is not depth in the middle of the attic but coverage at the edges, where insulation thins out exactly above the wall line that matters most for eave temperature. Look for compressed batts, gaps around ducts, and insulation that has been pushed aside during a past wiring or plumbing job.
3. Balance the ventilation
Ventilation keeps the underside of the deck at outside temperature. It only works as a balanced system: intake at the soffit and exhaust at the ridge in proportion. The most frequent problem is blocked soffit intake, often caused by blown insulation pushed into the eave during an unrelated project. A ridge vent with no intake does very little, and it can pull conditioned air out of the house.
4. Protect the eave and valleys during the next reroof
When the roof is replaced, ice and water shield carried well past the minimum at eaves and through every valley gives you a waterproof membrane exactly where the ice forms. It does not prevent ice dams. It prevents the water from getting into the deck when one occurs, which is the outcome that actually costs money.
Not sure whether your attic or your roof is the problem? Call HOMEMASTERS Bend at (541) 527-7002 for a free written estimate with no pressure and no obligation. See service details on the Bend location page.
What about heat cable
Heat cable along an eave keeps a channel open so water can escape. That is genuinely useful on a specific problem edge that cannot be fixed any other way, such as a north facing dormer valley over an unconditioned porch. It is not a repair. It runs on electricity through the coldest months, it does nothing about the heat loss that caused the problem, and it fails eventually. Treat it as a last resort rather than a first response.
Gutters, debris, and the September window
Blocked gutters do not cause ice dams, but they make the consequences worse by holding water at the eave and adding weight to a run that is already carrying ice. Ponderosa needle accumulation is the local culprit, and it collects fastest in the weeks before the first freeze.
September is the working window for all of this. Air sealing and insulation work happen in an attic that is not yet freezing, ventilation corrections need roof access on a dry surface, and a roof replacement needs warm dry weather because shingle sealant strips bond by solar heat rather than by adhesive alone. A full residential replacement in this service area runs $9,500 to $24,000, and a standard 2,000 square foot home with 50 year architectural shingles usually falls between $12,000 and $17,000, with the higher ceiling reflecting the heavier framing and fastening that snow load requires. Actual cost depends on home size, pitch complexity, material tier and decking condition, so a free written estimate is the only reliable figure.
Frequently Asked Questions
What causes ice dams on Redmond, Oregon roofs?
Heat escaping from the living space into the attic warms the roof deck and melts snow, and that meltwater refreezes when it reaches the cold overhanging eave. Repeated melt and refreeze cycles build an ice ridge that backs water up under the shingles. The cause is attic heat loss, not the weather itself.
Does a new roof stop ice dams?
Not by itself. A new roof with ice and water shield carried well past the minimum at eaves and valleys prevents the water from reaching the deck when a dam forms, which protects the structure. Stopping the dams from forming requires air sealing, correct insulation coverage and balanced ventilation. Call HOMEMASTERS Bend at (541) 527-7002 to have both assessed together.
Why does my neighbor not get ice dams?
Almost always because their attic runs colder than yours. Better air sealing at ceiling penetrations, more consistent insulation coverage at the eave line, clear soffit intake, or a steeper roof pitch will each reduce or eliminate dams under identical weather.
Is heat cable a good solution?
It is a symptom treatment. Heat cable keeps a drainage channel open on a problem edge, which is genuinely useful in a few specific situations, but it consumes electricity all winter, does nothing about the heat loss causing the problem and eventually fails. Fix the attic first and use cable only where the geometry leaves no alternative.
When should this work be done in Central Oregon?
Before the first freeze, which means late summer through early autumn. Attic work is far easier in a warm attic, ventilation corrections need safe dry roof access, and shingle installation needs warm dry weather for a proper seal. Call (541) 527-7002 to check current scheduling.
Get a free written roof and attic assessment in Redmond HOMEMASTERS Bend provides free written estimates with no obligation across Redmond, Terrebonne, Tumalo, Sisters and Powell Butte. Call (541) 527-7002 or visit the Bend location page to request a visit.
