Can I put topsoil sloped up right next to a house’s

Yes, sloping soil away from the house is good. The rule most builders follow is grade that drops at least 6 inches over the first 10 feet from the foundation [verify]. The mistake is piling topsoil up against the wall so the dirt sits too high near the house. That traps water against the foundation and can push it toward your wood siding or sill. Slope it down and out, not up and in.

Here is the simple version. Water needs somewhere to go. If the ground next to your foundation tips back toward the house, every rain feeds the wall. If it tips away, the rain runs off. So topsoil itself is fine. The slope is what matters.

Why the dirt next to your house holds water in the first place

When your house was built, a hole got dug for the foundation. Then that same dirt got shoveled back in around the walls. That backfill is looser than the packed ground around it. It drains slow. It holds water. So even good grading sits on top of soil that already wants to stay wet. That is why a little slope back toward the house causes outsized trouble here in New Hampshire.

Then winter shows up. Wet backfill freezes. Frost heave pushes on the walls and can move them inward over time. Pile soil high against the wall and you give that frost more wet ground to work with. You do not want that.

How high is too high

Keep soil down off the siding and the sill plate. A common guideline is to leave several inches of exposed foundation between the dirt and where the wood starts [verify]. Bury that wood and you invite rot and pests. Topsoil right up to the siding is one of the most frequent grading mistakes we see on a free inspection.

So your plan can work. Add topsoil, sure. Just shape it so the high point is right at the foundation and it falls away from there. Do not raise the whole bed so the wall is sitting in a bowl.

When grading alone is not enough

Sometimes the yard slopes the right way and the basement still gets wet. That tells you the problem is below grade, not just at the surface. Water is finding the floor wall joint, the seam where your basement floor meets the wall. Regrading the lawn will not stop that.

That is where interior drainage comes in. Our Forever Dry System is full-perimeter interior drainage with a sump pump, a 12-mil wall vapor barrier, and a dehumidifier. It catches the water that gets in and carries it to the pump before it reaches your floor. It is 100% guaranteed to be dry for life! You can read how it works on our basement waterproofing page.

People ask why we do not dig the outside and seal the wall. We have tried that approach over the years. In our field experience an exterior dig tends to fail in about two to three years as the backfill settles again. Interior drainage holds. That is the durable fix.

What this costs

Grading is something a lot of homeowners can shape themselves with a shovel and a rake. You do not need us for that part. If the water is getting into the basement and you want the Forever Dry System, basement waterproofing runs $3,000 to $30,000. The number moves with the size of your basement, how much wall we line, and the pump setup you need. If your wet space is a crawl space instead, crawlspace encapsulation is $3,000 to $25,000. We give you a real figure after a free inspection, not a guess over the phone.

If you have a sump pump already, ask about a battery backup. A charged backup battery can pump roughly a residential pool’s worth of water during an outage, about 15,000 to 20,000 gallons by typical pool-volume figures, which is enough to ride out most storms.

A little NH framing

Our spring melt and our heavy fall rains both test grading hard. Snow piles against the house all winter, then it all drains at once in March. If your soil tips the wrong way, that is when you find out. Shape the grade now while the ground is workable.

Want us to look? Call 603-610-1770 or book your free inspection. We serve New Hampshire, Maine, and Massachusetts, and we get you a quote within 24 hours. See what we stand behind on the 603 guarantee page.

Related questions

Does regrading my yard fix a wet basement? Sometimes. If surface water is the whole problem, better grading helps a lot. If water is coming up through the floor wall joint, you need interior drainage like our Forever Dry System. A free inspection tells you which one you have.

How far should water drain away from my foundation? A common standard is a drop of about 6 inches over the first 10 feet out from the wall [verify]. That keeps rain moving away from the house instead of pooling against it.

Will piling mulch against the house cause the same problem? Yes. Mulch, topsoil, or any bed held high against the siding traps moisture and can rot the wood. Keep the bed low and sloped away, with some foundation showing above the dirt.

Do you do exterior excavation to waterproof from outside? No. In our experience the outside dig settles and fails in about two to three years. We fix wet basements from the inside with the Forever Dry System, and it carries a transferable lifetime guarantee.