How to Prevent Snow from Damaging Your Foundation

Snow in Boston is pretty, for sure, but it's heavy and it melts, and when it does, all that water has to go somewhere. Usually? Right toward your foundation. Boston typically sees around 4 feet of snow each winter, so that's a lot of moisture sitting against your home.

TL;DR: Snow buildup around your foundation can lead to water infiltration, freeze-thaw cracking, and long-term structural damage. Keep snow cleared, gutters clean, and drainage working; especially before the spring melt hits.

Does Snow Really Damage Foundations?

Winter storms caused roughly $6 billion in insured losses in 2022, and a chunk of that comes from the kind of water and ice damage we're talking about here.

Here's the thing: a cubic foot of snow weighs anywhere from 7 to 20 pounds depending on how wet it is. Pile that against your foundation wall for weeks, and you're adding constant lateral pressure.

Then it starts to melt, and that's when the real trouble begins… water seeps into any crack it can find, freezes overnight, expands about 9%, and makes those cracks worse. Rinse and repeat all winter long and it's a recipe for leaks. Did you know that an estimated 98% of basements experience some form of water intrusion in their lifetime?

We see this constantly in the Greater Boston area. Historic buildings with beautiful old brick are especially vulnerable. When nearly a quarter of Boston’s houses were built before 1940, there’s a lot of aging brick and stone foundations around here. Newer poured concrete? Still not immune.

And all that snow can really pile up. The notorious winter of 2015 dumped over 110 inches of snow on Boston… just imagine the weight of all that pressing on your foundation and then melting into the soil.

How Snow Damages Foundation Walls (And Why Boston Properties Are At Risk)

Snow piles up, then melts during the day (sometimes on those random 50-degree February afternoons we get). Water runs down your foundation wall or pools around the base. If your grading is off or your gutters are clogged, that water sits there. It soaks in. Then temperatures drop again at night, and water expands when it freezes.

That expansion is incredibly destructive. It widens cracks, shifts mortar joints, and over time can bow or destabilize entire foundation walls. It shouldn’t come as a surprise that water damage and freezing are the second most common cause of home insurance claims in the U.S.

And if you've got an older property with a stone or brick foundation (which a lot of Boston buildings do), the mortar between those stones is often already weakened from decades of freeze-thaw cycles. One more bad winter can push things over the edge.

What You Can Do To Protect Your Foundation Before Winter Hits

Prevention is way cheaper than repair. The average cost for fixing a foundation is around $5,000 (and far more if the damage is severe or if you’re dealing with a historic property).

Clear Snow Away From Your Foundation

This sounds obvious, but most people don't do it. After a storm, shovel or blow snow away from your building (at least 3 to 4 feet if you can). Don’t just pile it up against the wall because it’s convenient. Your future self will thank you.

Check Your Grading and Drainage

Your property should slope away from the foundation (ideally about 6 inches over the first 10 feet). If water pools near your walls after rain or snowmelt, you’ve got a grading problem. Fix it before winter comes.

Also: clean your gutters and downspouts. Make sure downspouts dump water at least 5 feet away from the building. Extensions are cheap and they work.

Seal Cracks Before the Freeze

Even small cracks let water in. And once water’s in there and it freezes? That small crack becomes a big one. If you’ve got visible cracks in your foundation, even hairline ones, get them sealed before the first snow. We use high-quality sealants and repointing techniques that hold up through New England winters.

Insulate Exterior Walls (If Possible)

For historic or commercial properties, exterior insulation can reduce the freeze-thaw cycle’s impact on foundation walls. It keeps the temperature more stable and prevents that constant expansion-contraction that wears down masonry over time.

When to Call a Professional for Foundation Repair in Boston

Let’s say you didn’t prep in advance, or maybe you did everything right, but you’re dealing with an older building that’s already compromised.

Here’s when you need to call someone like JMS Masonry:

• Horizontal or stair-step cracks in brick or block

• Bowing or bulging foundation walls

• Water seeping into your basement during or after snowmelt

• Loose or crumbling mortar joints

• Efflorescence (that white powdery material on masonry - it means water is moving through your walls)

Foundation issues don’t fix themselves. They get worse, especially in freeze-thaw conditions, so addressing problems promptly is crucial.

If you’ve got a historic property that needs waterproofing, foundation stabilization, or masonry restoration, our team of experts has been doing this work in Boston for over two decades. We understand how older buildings are put together because our team was trained the old-school way to repair them properly.

Keeping Your Property in Tip-Top Shape All Winter

Winter in Boston is rough on buildings, but a little prevention goes a long way. Keep snow cleared, keep water moving away from your foundation, and if something looks off (a new crack, water where it shouldn’t be, mortar that’s starting to crumble), don’t wait until spring to deal with it.

At JMS Masonry & Restoration, we specialize in protecting commercial and historic properties through the winter. Whether it’s fixing freeze-thaw damage, waterproofing foundations, or full structural restoration, we’ve seen it all and we know how to fix it right.

Need help protecting your foundation this winter? Contact JMS Masonry & Restoration for a consultation. We’ll assess your property and help you avoid costly damage before the next storm hits.