Why Does Snow Melt Faster on Some Roofs?

When you take a look around your neighborhood after a snowfall, you see that snow seems to melt faster on some roofs than others. Primarily, the snowmelt is due to poor insulation. The warm air from inside the home gets into the attic, which warms the underside of the roof. The snow begins to melt and flow down to a colder part of the roof where it re-freezes, forming what is known as an ice dam. This is just one of the issues caused by snow melting on your roof.

In this article, we’ll take a closer look at the problems caused by melting snow and how you can prevent damage to your roof.

Potential Problems Caused by Melting Snow 

Several issues can occur when the snow melts on your roof. We’ll explore some of those issues below: 

Formation of ice dams 

The warm air rising from your living spaces in the winter warms the underside of your roof. This causes the shingles to warm, melting the snow. The snowmelt water drips down to the colder edges of the roof and re-freezes. Over time, this ice patch will thicken into an ice dam, which blocks further snowmelt. An ice dam can cause water to seep under shingles and into your home, leading to leaks and structural damage. The best way to avoid this is to ensure you have adequate insulation and venting in your attic. However, cleaning out gutters and downspouts in the fall can also decrease your risk of ice dam formation, as well as making sure to keep snow off the edges of your roof with a roof rake. Finally, installing heat trace cables in your gutters can keep the snowmelt flowing, preventing water backups.

Formation of icicles 

The same conditions that cause ice dams can cause icicles as well. Though icicles may seem harmless and can be neat to look at, they can cause damage to your roof and gutters. Not to mention, they can fall and hurt someone walking under them, making them a liability. One of the best ways to prevent icicles is improving insulation and eliminating rooftop air leaks. However, you can also remove them with your roof rake, but if you do, be sure that no one is standing or walking underneath.   

Condensation in attic 

Suppose you have ice dams and water retention on your roof, your chances of getting excess condensation in your attic increase. Moisture buildup can be a significant issue leading to mold and wood rot. The answer to this is proper ventilation to prevent snowmelt on the roof. However, a quick fix can be to plug leaks in the attic floor so moist air from below can’t enter. Also, keep in mind that any appliances may increase moisture if they are not working properly.

Exacerbates Existing Problems 

In addition to potentially causing new issues, snow melting on your roof can exacerbate any existing issues you may or may not know you had. It can cause unsecured roof flashing to become loose, pry open gutter seams, dislodge unstable shingles, and so much more. Therefore, it’s a good idea to have your roof inspected and have any maintenance work done before and even after winter.

Preventing Snow Damage to Your Roof

Dealing with issues caused by snow and snowmelt on your roof can be difficult, but there are some things you can do to get ahead of it and prevent issues before they get started.

  • Keep your roof clean all year long.
  • Use snow guards to keep the snow from accumulating on the roof
  • Use a snow rake when removing snow from your roof. Don’t use ice picks, as these can result in damage to your shingles and, ultimately, the roof as a whole.
  • When the snow starts to melt in the spring, don’t use snow salt. Allow the warm weather to melt the snow and ice naturally. Snow salt can cause damage to your roof.
  • This should go without saying, but you want to avoid using a snowblower or snowplow on your roof to remove the snow, as these can both cause significant damage.


No matter what, it’s a good idea to schedule your roof inspection with A&J Reliable. We will be happy to look at your roof to verify the health of your roof and look for any winter damage.