Ice Damming

Definitive Development are experts at analyzing and diagnosing your Total Roof System and prescribing the best solutions keep your roof healthy. Alaska is a harsh climate. Your roof is your primary defense against the elements. Did you know that your roof is more than just the roofing material you see from the outside? Your roof is an entire system. It includes your insulation, ventilation, trusses/joists and sheathing as well as your roofing and underlayment.  In order for it to protect you and your house well, all the parts of that system need to function properly. When it isn't functioning properly, you can have problems like ice dams and condensation occur. when these go unchecked, your roof can leak and collect moisture which begins to rot your sheathing, trusses, and sometimes into the walls.

The diagram above shows a typical attic roof with proper ventilation and insulation. The insulation keeps heat from escaping from the house into the attic. The ventilation removes any residual heat and moisture from the attic, protecting the roof from condensation (water forming on the inside of the attic-see below) and ice dams (ice frozen to the inside of the roof caused by snow melting outside - see below). When these structural components are working together properly, your Total Roof System is protecting your house from the elements, moisture damage, and heat loss. 

Roof Ventilation

Total Roof System


When your roof doesn't have enough insulation or ventilation, heat can build up in the attic, creating what we call a "hot roof". In the winter, a hot roof will melt snow and cause icicles and ice dams. These occur when the water from the melted snow flows down the roof and meets the eave, where there isn't any heat underneath. That water re-freezes and builds up, creating icicles and a dam. The water above begins to pool and back flow under the roofing, causing leaks that can travel along your ceiling or into your wall cavity. These leaks can ruin drywall, cause mold, and rot the structure of your home over time. Definitive Development can supplement your insulation and ventilation to keep these problems from happening.

If a roof is equipped with inadequate ventilation and remains cold for long periods of time, condensation can occur. Without proper ventilation, moisture from your house can build up in attic spaces. When this warm, moist air meets the cold surfaces in your attic, the water condenses and freezes inside the attic. When it warms up, the ice melts and can cause leaks in your ceilings or walls, just like an ice dam. By installing proper ventilation, your roof system will remove moist air, keeping you dry and safe.