How do you fix a wet basement?

You fix a wet basement by stopping the water inside, not outside. The durable fix is a full-perimeter interior drainage system with a sump pump, a wall vapor barrier, and a dehumidifier. That is our Forever Dry System. A typical New England basement runs $3,000 to $30,000, and it is 100% guaranteed to be dry for life.

Let us walk you through why.

Why your basement gets wet

When your house was built, the crew dug a hole, set the foundation, then pushed the dirt back in around it. That dirt is disturbed backfill. It is looser than the packed ground around it. So it drains slowly and holds water right against your foundation walls. Rain and snowmelt collect there. Then it pushes in.

Up here we also get frost heave. The wet soil freezes, expands, and pushes your walls inward over the winter. That stress opens up cracks. Water finds them.

Most leaks show up at the floor wall joint. That is the seam where your basement floor meets the wall. Water under pressure comes up right there. It can also weep through cracks or wick through the block.

The fix that lasts

Here is what the Forever Dry System does. We cut a channel around the inside perimeter of your basement and install drainage that catches water at the floor wall joint. That water runs to a sump pump. The pump (1/2 hp for every 120 feet of drain) sends it back outside, away from the house. We hang a 12-mil vapor barrier on the walls so moisture coming through the block gets caught and routed down to the drain. Then a dehumidifier keeps the air dry.

It manages the water instead of fighting it. That is why it holds.

We do not do exterior excavation waterproofing. We have dug those jobs up and watched them fail in about two to three years. You dig down, seal the wall, backfill, and the new disturbed soil holds water again. Interior drainage is the durable answer, so that is what we install.

Want a battery backup? It is a battery-only system. A charged backup pumps roughly a residential pool’s worth of water, around 15,000 to 20,000 gallons, when your power goes out in a storm. That is the storm you most want a working pump for.

What drives the cost

A wet-basement fix at $3,000 to $30,000 moves with a few things. How many linear feet of perimeter you have. Whether your floor wall joint is poured concrete or block. Whether you need one sump or two for a bigger footprint. Whether you add the battery backup and the dehumidifier (we recommend both). Every job gets a free inspection and a free estimate, and we get your quote back within 24 hours.

What you might not need

If the water you are seeing is only one crack in a poured wall and the floor stays dry, you may not need the full system yet. A crack injection at $1,000 to $3,000 could be all you need. We will tell you that to your face. If your problem is in a crawl space and not the basement, that is crawlspace encapsulation, not Forever Dry. Different fix, different price at $3,000 to $25,000.

We would rather size it right than oversell you.

A quick word on the building science. The U.S. Department of Energy’s Building America program notes that a good chunk of a home’s heat loss can come through an uninsulated foundation, so drying and sealing the basement helps comfort too, not just the water. (See the DOE Building America Solution Center, basc.pnnl.gov.) And per the Insurance Information Institute (iii.org), standard homeowners policies typically do not cover groundwater seepage, so fixing the source matters.

Get it looked at

Call us at 603-610-1770 or book your free inspection. We will tell you what your basement actually needs.

The Forever Dry System is 100% guaranteed to be dry for life, and that warranty transfers if you sell (conditional). See the 603 guarantee.

Learn more about basement waterproofing, crawl space services, structural and foundation repair, and foundation repair.

Related questions

Can you waterproof a basement from the inside? Yes, and that is how we do it. Interior perimeter drainage to a sump pump, plus a wall vapor barrier and a dehumidifier. We do not do exterior excavation because in our field experience it fails in about two to three years.

Does a sump pump fix a wet basement on its own? A sump pump is part of the fix, not the whole thing. Without perimeter drainage feeding it, water still sits at your floor wall joint. The pump needs the drain catching the water first.

Will homeowners insurance pay to fix a wet basement? Usually not. Per the Insurance Information Institute (iii.org), standard policies typically exclude groundwater seepage and surface water. Fixing the source is on you, which is why a guaranteed system is worth it.

Is a wet basement just cosmetic, or a real problem? A real one. Standing water and damp block lead to mold, wood rot, and pressure on your walls. NH frost heave makes it worse each winter. Sooner is cheaper than later.