How to Prevent Ice Dams on Your Roof
A key aspect of winter weather home maintenance that homeowners need to know is ice dam prevention. Ice dams can occur from fall through spring on the edge of your roof after a snowfall. These phenomena can cause damage to structures, such as mold in the attic, which can be very severe. Here’s how ice dams form, how to prevent and remove ice dams, and who to call if one should cause damage to your home.
How ice dams form
When snow accumulates on a roof, a cycle of melting and refreezing occurs. In a perfect world, the snow would melt off the roof, enter the gutters, and flow harmlessly to the ground. However, two key factors can cause problems: the outside temperature and the temperature in your attic.
The warmer your attic is, the more melting will occur. Normally, the resulting water would flow off the edge of the roof. But, when the outside air temperature is very low, the edge of the roof stays below freezing and the water refreezes when it gets to that point. This ice then forms a line, or “dam,” at the edge of the roof. As more snow melts, it also refreezes when it gets to the “ice dam,” and the dam keeps getting bigger.
To make matters worse, ice dams are somewhat of a silent destroyer, as water enters the home gradually. Also, it typically damages the attic area first, which isn’t a place that homeowners usually frequent. By the time you realize there’s a problem, it’s when the damage has spread from the attic and into other areas of the home.
Furthermore, contrary to some popular opinions, gutters do not cause ice dams. However, an ice dam can extend into a gutter if weather conditions permit. So, how can ice dams be prevented in the first place? In many instances, the answer is… snow removal, insulation, and ventilation!
Ice dam prevention tips
Remove the snow from your roof
It’s common for homeowners to rev up their snowblowers and dig out their snow shovels after each winter snowfall to clear their driveways and sidewalks. But not to be ignored is the snow that has also fallen on the home. Hence, a key tip to prevent an ice dam from forming is to regularly remove snow from your roof. Here are some roof snow removal tips:
- Remove the first three to four inches of snow from your roofline. This is best done with a roof rake or a long-handled brush that can permit you to remove the snow without the use of a ladder.
- Make sure that downspouts are clear so that melted water has a chance to drain properly.
- If your area has received more than a foot of snow, it’s best to clear not just the first three to four inches along your roofline, but as much as possible. A foot or more of snow has the potential to cause your roof to cave in or collapse.
Adding roof maintenance into your snow removal routine is a great way to prevent ice dams after a snowfall, but there are other more long-term solutions. Read about them below.
Insulate your attic
A well-insulated attic helps prevent the melt/freeze conditions in which ice dams form by keeping the attic temperature lower. Since the main cause of ice dams is an overly warm attic, a good ice dam prevention solution is lowering the attic temperature.
Installing additional insulation in the attic area is as easy as laying extra layers across the existing ones, or having more insulation blown in. However, there are limits to this procedure, and it’s best to hire or consult a professional roofer or insulation contractor.
Also, if you notice bare sections on your roof while the rest of the roof has snow, there may be insufficient insulation under the bare areas. To confirm this, have your attic inspected and then remedy the situation if necessary.
You should also inspect the weather-stripping and/or insulation on attic stairways or hatchways. Make sure it’s in good shape and seals well. This will help keep the warmth out of the attic area and prevent ice dams.
Ventilate your attic
Even with optimal insulation, there is still heat leakage into the attic. This is when the value of attic ventilation becomes apparent. Without adequate ventilation, heat will build up regardless of the amount of insulation.
First, inspect your attic to be sure that the existing vents have not been covered by insulation or other objects. If this has occurred, remove the insulation (or other material) from the soffits so air can move through them freely.
The usual recommendation for venting is one square foot of vent for every 150 feet of attic floor area. If your home does not have that ratio (many older homes do not), hire a contractor to remedy the problem.
If your home does not have vents, consider adding a ridge vent. Again, a professional roofer or contractor can give sound advice on the procedure. If you’re not sure about the condition of your roof, contact a professional roofer for advice or assistance.
Removing ice dams
If an ice dam has formed on your roof, that doesn’t mean that water damage and mold growth occurred in the home. Yet, it’s always best to remove the ice dam as you notice it, well before it has a chance to cause damage to your property. Safely removing an ice dam can be done in several ways:
- Simply knocking an ice dam with a roof rake is often enough to dislodge it. Doing so allows water to drain again.
- If the ice dam is too large, consider cutting a channel through it. That will allow any standing water it’s blocking to drain properly.
- While you never want to use rock salt on your roof, you can use calcium chloride to melt the ice dam and allow water to once again flow freely.
- Finally, another option is to hire a snow removal contractor to resolve the problem.
Tip: Installing a water membrane underneath the roof shingles can act as extra protection. It helps prevent water from seeping into the building.
For water damage restoration, contact PuroClean!
Now is the time to make winter weather maintenance a priority. But even with all ice dam prevention measures in place, you may still be susceptible to an ice dam that could create a water loss.
If you notice water damage (marks, drips or lines) on ceilings or exterior walls, it could mean that an ice dam has formed, and ice and water have forced their way into your attic. In addition to fixing the cause of the ice dam, it’s important to recognize that this is a true water damage situation.
The problem should be remediated by trained professionals to prevent further damage to the structure (such as rotting), and to prevent mold growth — a health hazard to people living in the home.
And that’s where your local PuroClean office can help in restoring your water-damaged property to a pre-loss condition. For more information on PuroClean’s water damage restoration services, as well as mold removal services, contact your nearest location today.