All About Ice Dams
Learn what causes ice dams and how to prevent them.
It’s that dreaded time of year again when our worst insulation and air-sealing fears materialize as ice dams on our roofs. Ice dams are common with inadequately insulated and air-sealed homes in cold climates, and they can be the culprit behind major problems. This slide show provides all the information you need to know about what causes ice dams and how to prevent them.
In the winter, ice dams form on many homes in the northern part of the country. While the water leaks that they may cause are often attributed to poor attic ventilation or to a roof in need of repair, the more common culprits are air leaks and insufficient insulation. Senior editor Martin Holladay explains how ice dams form and how they can be prevented.
Find out why ice dams are a sign of an inefficient house
Proper insulation and roof ventilation can stop ice dams from forming, prevent damage and lower energy bills
Ice dams form when a home’s escaping heat warms the roof sheathing and melts the underside of the snow layer on the roof. Water trickles down the roof until it reaches the cold roofing over the eaves, where it freezes. After a while, the ice at the eaves gets thicker and thicker, forming an ice dam. Eventually, water backs up behind the ice dam.
Understand when to vent your roof, when not to, and how to execute each approach successfully
Get expert advice how to prevent ice dams in valleys