What Causes Ice Build-Up on Homes?

When the weather is cooler than cool, it can turn ice cold. Unfortunately, this can lead to a lot of ice on and around your home. There are few things that can make you lose your chill faster in the winter than ice-related falls or damage to your home. Excessive ice build-up can create a number of potentially dangerous situations during the winter, so knowing what causes it (and more importantly, how to prevent it) is an important part of staying safe as temperatures drop.

Ice Build-Up

There are a few different ways that ice can build up during the winter. The most basic ice buildup is just a thin layer of ice that covers large portions of the house, sometimes accompanied with snow or other precipitation. This usually isn’t that big of a deal. Of greater concern are large icicles, sheets of ice and snow that build up on the roof, frozen gutters and built up ice at the edge of the roof known as an ice dam. These can be dangerous in several ways, both to you and to your house.

Frozen Gutters

When ice freezes in your gutters, it places extra strain on the screws or clips holding the gutters in place. Overflow can result in icicles hanging from the gutters, and if the buildup gets too heavy it can actually pull the gutters away from your roof. This is particularly dangerous because that heavy ice can then fall to the ground… bringing part of your gutter with it.

Ice Dams

If a portion of your roof becomes warm enough to melt some of the snow and ice on top of it, an ice dam can form. That melted snow or ice will trickle down the roof as water, reaching the eaves or gutter and encountering much colder materials where it will freeze again. This process continues until there is a buildup of ice at the very edge of the roof, with liquid water attempting to flow underneath it. The ice can overflow onto your gutters, while the water forces its way under shingles and possibly through other materials until it freezes and expands. The longer the ice dam continues this process, the thicker it becomes and the more damage it can do.

Other Forms of Ice

Ice sheets and icicles also present dangers during the winter. Icicles form when liquid water gradually drips at the same spot over time, freezing more and more until it grows large enough to potentially break free and fall to the ground. Ice sheets form similarly to ice dams, but instead of melting entirely the heat of the roof only melts a small portion of the ice sitting on it. The remaining ice is able to shift under its own weight due to the thin layer of water underneath it, and in some cases may slide down the roof and fall to the ground.

Removing Ice Build-Up

Care should be taken when trying to remove any form of ice build-up. Don’t use any sharp implement as it can damage your roof, gutters or walls. Instead, tap away at the ice with a blunt mallet or pole. Work in small sections, making sure that there is someone with you to brace your ladder in case the ice shifts. Apply a calcium chloride ice melter to the ice beforehand, if possible, to melt as much of it as you can (but don’t use rock salt or other chemicals that can damage your home.) Take every precaution you can before you start trying to remove the ice, because even when you’re prepared, it can be dangerous.

Preventing Build-Up

To prevent ice build-up, work on improving ventilation in your attic to ensure even heating and consult an energy efficiency expert to see if there are other steps you can take. Use a snow rake to remove snow and ice buildup from the roof before it can become a problem, and clean your gutters thoroughly before winter weather sets in. If you have a continuing problem with build-up, you might also consider replacing some or all of your existing roof with a standing-seam metal roof with a water-repellant membrane underneath it.