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How to Prevent Ice Dams on Roofs
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How to Prevent Ice Dams on Roofs

Posted by SnoBlox-Snojax on Dec 20th 2021

On-and-off intervals of melting and freezing generate ice dams. Snow forms an insulation layer on your roof which warms the air in your attic.

Snow melts and rolls down the edge of roofs and the soffits as a result of the heated attic. If the melted snow isn't allowed to drain the way it should, it'd freeze and stack up, causing ice dams. If this continues, water would eventually make its way beneath the shingles and into the attic throughout the winter. Unfortunately, the ice dams will spread up the roof.

Water can soak into your insulation and cause it to deteriorate. As a result, heated air from your home rises into your attic, causing the ice dam to expand.

You can't stop the snow, and you can't stop the thaw! Isn't it?

You may ask - how do I prevent ice dams on my roof?

To be ready for the next wave of ice along your roof's edge, a little forethought is required. Climbing a ladder to clean up the mess is less likely required if you're prepared. Besides that, you will also reduce the chances of a leaking roof and ice dam water damage.

I have compiled a step-by-step guide to sort things out to prevent future problems.

Ice dams can be prevented. Here is how to fix it!

Let's proceed!

Materials Needed to Prevent Ice Dams On Roofs

Fiberglass batts or loose cellulose insulation are both options. The tools and resources you'll need will vary depending on your pick. You can rent an insulation blower from a building supply store if you decide to blow in cellulose.

1. Work gloves

2. Dust face mask

3. Insulation knife

4. Measuring tape

5. Insulation blower for cellulose

6. Expanding spray can, etc.

Now that you know the equipment needed to remove ice dams from roofs let's move into the main purpose of this article.

Ways to Prevent Ice Dams on Your Roof

1. The Use of Fiberglass Batts

Ensure you put on a dust mask to avoid inhaling fiberglass fibers as a preventive measure. Also, wear work gloves to prevent skin irritation.

After taking this measure, seal gaps in the ceiling around plumbing vent pipes and electrical wires with expanding foam spray. After that, measure the length of channels between ceiling joists.

Next is to cut fiberglass batts to size with an insulation knife. Then, lay the insulation between the joists with the paper vapor seal side on the bottom. Once the joists have been filled with batts, add another layer of batts across the floor joists.

2. The Use of Cellulose Insulation

Firstly, spray the expanding foam around ceiling gaps to transfer heat into the attic. Then make points throughout the attic structure twelve inches from the ceiling. These marks help you to know when insulation is deep enough.

After that, look for a spot outside to set up the blower below an attic window or vent. However, ensure you wear a face mask and crumble loose insulation into the blower's hopper. Then pass the hose up to the attic.

Lastly, stand in a central position near the attic access door. Then blow insulation into the edges and gradually fill the whole space.

How to Prevent Ice Dams On Metal Roofs

Do you live in a house built with metal roofs and not the usual traditional roof? Let's discuss the ways to prevent your metal roofs from ice dams.

Firstly, keep cold outside and heat the interior part of the attic with insulation rated at least R-38. However, ensure the attic stays air-tight by closing openings around wiring, plumbing, and exhaust fans.

Remove debris from roof vents and soffits. This will prevent them from catching and holding melting runoff. You can use a roof rake to remove snow from the roof and reduce the chance of ice dams accumulation.

Lastly, consistently clean gutters and downspouts to reduce clogs that slow down runoff.

To ensure you are in a safe mode, you can ask a building contractor about several metal roof coatings that help shed ice and snow. Besides that, you can repaint your metal roof with a color that absorbs warmth during the day.

Signs of Ice Dams on Your Roof

Tackling a problem immediately you note prevents you from all futuristic dangers. Similarly, having an in-depth knowledge of signs of ice dams on your roof prevents any problem accrued to it.

Here are three significant signs that ice dams have developed on your roof:

1. Large Icicle

Many homeowners mistakenly believe that any icicles on the roof's edge signal the presence of an ice dam. This is a common misconception, however, exceptionally enormous icicles can be caused by an ice dam.

Examine the state of the icicles on your house. Do the icicles appear to be hanging directly from the shingles on your roof or from your gutter troughs?

A big ice structure is also likely connected to icicles that resemble a wave coming over the edge of your roof.

Ice dams are unlikely to be the cause of little icicles and icicles that form on the underside of your roof or gutters.

2. Leaks In The Interior Part of Your House

Ice dams can cause water damage inside your home by preventing regular drainage off your roof. You might see new stains, ceiling cracks, or peeling paint portions.

Ice dams that are severe enough can result in actively dripping leaks on your home's upper floors.

Water damage is most likely to happen within a few feet of the external wall, immediately below where the dam has caused water to back up.

3. Hot Spots

The melting and refreezing of snow on your roof causes ice dams to grow over time. This process frequently begins in locations known as hot spots. A hot spot develops when heated air escapes to your roofs, such as around vents or a skylight.

You can go outside after it has recently snowed to look for hot spots. If you can see sections of your roof clear of snow, you have a high danger of ice dams. Keep track of where the bare patches appear, as these are likely to be hotspots.

Final Words

Preventing ice dams isn't as hard as you may think. Following the above processes will make your plans come to reality with no technical hassle whatsoever. 


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