Prepare for Snowmelt Runoff at Your Home

A quick scan through the list of states and their average annual snowfall reveals Alabama at 1.6 inches, Georgia at 0.7, Mississippi at 0.9, and Tennessee at 6.3 inches. That, of course, is the average. So much for that this year.

Snow, sleet, freezing rain, and ice can cause significant damage to your home. Then there’s the impact from freezing temperatures coupled with power outages. It’s like a growing cascade of weather issues and related challenges.

What Happens After Snowmelt

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Rooftop Snow

Our roofs, gutters, and downspouts are designed to shed rainwater, bring it to the ground, and take it away from the foundation. Snow brings a different set of issues.

For starters, snow builds up on the roof over time. This is in contrast to rain where the very first drop starts moving off the roof. This additional accumulation represents a great deal of water.

Water Buildup

The general rule is that 13 inches of snow is the equivalent of one inch of rain. On a 2,800-square-foot roof, that would amount to almost 1,800 gallons of water. Of course, with dry snow, that would be less water, perhaps around 1,000 gallons. But with heavy wet snow, it could amount to more than 5,000 gallons.

There’s also freezing that goes along with the snow. Daytime thaw followed by nighttime freezing forms ice on the roof. Water in the gutters also freezes. This causes further melting to run directly over the gutters and onto the foundation.

Landscape Snow

Once the rooftop snowmelt reaches the ground, it meets up with the snow that originally fell on the lawn and landscape. It’s been melting, too. All this builds up a great deal of water on the surface, saturates the soil, and forms water flow underground.

That underground water is moving directly toward your basement or crawl space due to the clay bowl effect. This occurs when the soil around the foundation has a different drainage factor than the surrounding soil.

This happened as a result of the original excavation followed by backfilling around the completed foundation. That soil is much looser than the undisturbed soil. This, in effect, creates a bowl around the foundation, allowing water to develop hydrostatic pressure on the foundation walls.

That water finds any cracks or opening and it can cause cracks. All this leads to leaks and even flooding in the basement or crawl space.

Freezing Temperatures

As noted above, freezing temperatures block downspouts, setting up snowmelt running directly off the roof and onto the foundation. Exposed water pipes can also freeze and burst. That leads to flooding and requires that you immediately shut off the water supply to your home.

Pool pumps and pipes can also freeze. Ideally, the pump will be set up to move the water continuously through any freezing temperatures, preventing frozen pipes and keeping the water circulating in the pool.

Freezing temperatures can also lead to frost heave and the resulting foundation shifts. Moisture collects under slab foundations and when frozen expands. This typically causes cracks within the home rather than outside walls.

Electric Power Loss

Losing electric power sets up the potential for significant flooding. If your basement uses a sump pump to remove water, it needs a battery backup system to make sure it continues to do its job during a power loss.

Prepare Your Home for Snowmelt

As you can tell, snowmelt can cause a number of problems. The best way to avoid these is preparation. Here are our tips.

  • Fix Basement Cracks. Water finds the tiniest of openings to enter, and if that’s accompanied by freezing, it can expand the cracks. For this reason, it makes good sense to fix any cracks well before winter weather or spring thaws.
  • Remove Rooftop Snow. If the temperatures are expected to remain low along with further snowfall, it can be worthwhile to remove some or all of that snow. A roof rake can be used to remove snow without climbing up on the slippery roof. Also make sure to keep the snow at least  four to six feet away from the perimeter of your foundation.
  • Keep Gutters and Downspouts Clear. As you prepare for winter, make sure the gutters are clear of leaves and that the downspouts are free of any obstructions. It’s also wise to install extensions that move the water away from the foundation.
  • Consider Landscape Slope Grading. Once the water is off the roof and onto the ground, it needs to continue to flow away from the foundation. This is best facilitated by a gradual slope away from the foundation.
  • Add Attic and Foundation Insulation. Any heat escaping through the attic or around foundation walls can start snowmelt, building up water that will find its way to the foundation. Add sufficient insulation to not only prevent this but also save on utility bills, including air conditioning costs.
  • Install a Basement Drainage System. Install an interior drainage system and sump pump system that can collect any leaks, remove them, and prevent serious water damage and flooding.
  • Invest in a Backup Sump Pump. Make sure any existing sump pump drain lines are open and that you have a backup arrangement in place. Failure of the sump pump can lead to extensive flooding. Also, watch for freezing of the drain lines.

As you prepare for snow and the resulting snowmelt, it’s always a good idea to call on the professionals. Schedule a free foundation inspection by the local foundation repair experts at AFS Foundation & Waterproofing Specialists.


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