Ice dams are caused by poor insulation and ventilation. So no, will not prevent .or cause. ice dams. Gutter Helmet® can, however, help reduce the amount of ice build-up in your gutters that can cause gutter seams to split, hangers to loosen, and gutters to pull off the house. For more information on the cause and prevention of ice dams, please contact your local Professional Gutter Helmet® dealer by visiting the ‘Where to Buy’ page. Your dealer can also guide you to additional sources of information. Because the ice that used to accumulate in your gutters now goes over the panels, some customers report an increase in icicles. If that is a concern to you, Gutter Helmet® offers an exclusive Helmet-Heater option to prevent icicles and help prevent the damage caused by ice dams. Contact your Professional Gutter Helmet® dealer for more information.