What Causes Ice Dams on My Roof?



Winter weather is not typical for most countries. This usually means snow, arctic winds and colder temperatures. For some, it is their favorite time of the year.

However, winter is often a time of the year that they need to be aware of potential hazards. Some incidents to be aware of include the possibility of freezing pipes, slippery sidewalks and walkways, clogged gutters and problems with heating systems and exhaust vents.


Another problem that can occur are ice dams on your roof. There is plenty of information available online on how to remove ice dams . You can do it yourself or you can trust professionals to get the job done right. Do not risk your personal safety if you do not have to.


Here are a few reasons why ice dams can form on your roof:

1. Changing temperatures

Some ice dams form because of very slight shift in temperature changes. There will be some days where the temperatures are above freezing during the day, but drop down below freezing overnight. As the snow melts and then refreezes, this is when ice dams will form. That ice will hang over your roof or garage in corners and overhangs. In this kind of situation, it is a good idea to remove as much snow from your roof as possible during the day. The less snow that you have on your roof, the less there is to refreeze overnight to cause ice dams to form.


2. Radiant heat

Another way that ice dams can form on your roof in the winter is radiant heat. Radiant heat is transmitted through electromagnetic waves. When these waves are received, they are converted into heat. Even if temperatures are below freezing point throughout the day and night, radiant heat can still cause ice dams to occur. Unfortunately, there is no way to prevent this from happening. It is not something that either you or the weatherman can predict. The only effective way to guard against this, is by removing as much snow from your roof as possible.

3. Having a warm attic

The most common reason why ice dams form is due to having a hot or warm attic. This can happen in various reasons, it may be due to not having enough insulation in the attic, or the attic may not be properly ventilated. There may also be some poorly ventilated areas that can cause warmer air to filter through into your attic. Electrical outlets, attic doors and light fixtures are just some of the usual problem areas. There may also be some non-insulated heat ducts in the attic, which can make it more difficult for that area to cool effectively. Some home ventilation systems end in the attic instead of sending warmer air outside. That means that the heat is trapped in the attic with nowhere to go. A good way to prevent this problem is by having an energy-efficient audit done for your home. Professionals will know what problem areas to look for and give you recommendations that are effective and can help save you money in the long run.


4. Perfect temperatures

A lot of ice dams are created when temperatures are either just under or are exactly at the freezing point (30 to 32 degrees). It doesn't take a lot of temperature variation for them to form, especially if you have a lot of snow on your roof. Freezing and thawing cycles are when many ice dams are more likely to form. When this happens, it's a good idea to lower the temperature on your thermostat for just a few degrees. A simple step that can help you save money in both energy costs and removing stubborn ice or snow from your roof and garage overhangs.

5. Clogged gutters

Gutters are prime areas for ice dams. Metal gutters become cold in winter months, where you frequently find rain and snow in colder months. When that rain or snow freezes, it takes up more space in those gutters as ice. Eventually, this ice platform expands and creates ice dams in the gutter and roof areas. For better results, you should consider cleaning out your gutters on a regular basis (even in winter when you can), replace any metal gutters with plastic gutters or install gutter systems that have guards or screens over them to prevent less leaves and moisture from filling them.

6. Poor attic insulation

The attic is one of the rooms in most homes that is used the least. It is often used to store belongings that are often forgotten. Every attic should be properly insulated. Good insulation can help reduce the likelihood of ice dams developing on your roof. While it may not entirely prevent ice dams from forming, a well-insulated attic can help tackle the problem of variable changes in temperature. When it is time to remodel or update your current insulation needs for your home, take some time to consider and plan to update your attic insulation too. It can make that area of your house a lot more comfortable and protected in any kind of weather condition.


These are just some of the common reasons why ice dams form on homes during the winter months. They can be annoying and rather stubborn to remove at times. It can be very aggravating when you continuously have to clear them from your garage and rooftops during regular thaw and freezing cycles. However, a little preventive maintenance in your heating system and gutters can help save you time and money in the long run. You can spend a little now on upgrades and ice dam removal, or you can pay a lot more later in terms of repairs if you neglect these problems for too long. Ice dams will probably happen on a regular basis during an average winter, no matter how prepared you may be for them. Taking proactive steps to reduce their likelihood and clearing them after they form on your rooftops are the most effective ways of reducing long-term damage and keeping your roof and garage intact for many winters to come.