How to Prevent Ice Dams: Proven Attic & Roof Fixes That Actually Work

 

Ice dams happen when heat escapes into the attic, melts roof snow, and that water refreezes at the colder eaves. To lessen or prevent ice dams, focus on keeping the roof cold and improving drainage:

 

1. Improve attic insulation (biggest impact)

• Add or top off attic floor insulation (aim for R-49 to R-60 in cold climates).

• Make sure insulation is evenly distributed, especially near exterior walls.

• Install baffles at the eaves so insulation doesn’t block airflow.

2. Air-seal the attic

Stop warm air leaks that cause snow melt:

• Seal around light fixtures, bath fans, attic hatches, duct chases, and wiring holes

• Use foam or caulk for gaps and weatherstripping on attic access doors

3. Improve attic ventilation

• Ensure proper soffit intake and ridge or roof exhaust vents

• Balanced airflow keeps roof temperatures consistent

• Clear blocked soffit vents

4. Fix bathroom & kitchen exhausts

• Vent fans outside, not into the attic

• Insulate and air-seal fan ducts to prevent heat loss

5. Roof-edge solutions (secondary help)

• Install ice & water shield under shingles at eaves (best during reroofing)

• Add heated cables only as a short-term or problem-area solution (not ideal long-term)

6. Remove excess snow safely

• Use a roof rake after heavy snowfalls (especially the first 3–4 feet from the edges.

• Have a professional roofer remove ice dams and snow.

7. Gutter maintenance

• Keep gutters clean so melted water can drain

• Ensure gutters are pitched correctly and securely fastened

 

Quick summary (best → least effective)

1. Air sealing

2. Attic insulation

3. Proper ventilation

4. Snow removal

5. Heat cables (last resort)

 

We can give you a targeted fix that makes sense for your house and budget.