Drainage Around House Foundation: 4 Fixes That Work

Good drainage around house foundation walls does four things, in this order: it carries roof water away from the walls, it shapes the soil so rain runs away from the house, it catches groundwater before it reaches the foundation, and it keeps the footing drain at the base of the wall working. Most wet basements can be traced to a failure in the first two, which are also the least expensive to fix.

Here is each step, what it involves on a Massachusetts house, and how to tell when the problem has moved past a weekend fix.

1. Get roof water away from the walls

A roof sheds a lot of water, and the gutters gather it into a few downspouts. Where those downspouts empty decides where that water ends up. Gutter repair and cleaning is a gutter contractor's job. What happens at the bottom of the downspout is drainage, and there are three common options:

• An extension or splash block. Simple and cheap. It works when it carries the water onto ground that slopes away and doesn't run back. Extensions get knocked off and buried in snow.
• Buried solid pipe to daylight. The downspout connects to a solid pipe underground that runs downhill and comes out at a lower point on the property, often through a pop-up outlet in the lawn.
• Buried solid pipe to a dry well. When there is no lower spot to drain to, the pipe carries the water to a dry well a safe distance from the house, where it soaks into the ground.

Two details matter in a New England winter. Buried downspout pipe needs a steady downhill fall so it drains completely and doesn't freeze solid. And roof water should not be piped into the footing drain at the base of the wall, which is meant to handle groundwater only.

2. Grade the soil away from the foundation

The International Residential Code, which the Massachusetts residential building code is based on, calls for the ground to fall at least 6 inches within the first 10 feet away from the foundation (IRC section R401.3). On many older houses the soil beside the wall has settled over the decades and now tips toward the house instead.

Regrading means building that soil back up with a dense soil that sheds water, sloping it away, and keeping the finished grade below siding and wood trim. Raised garden beds and edging that trap water against the wall should be reworked or moved.

Hard surfaces count too. A patio, walkway or driveway beside the house should pitch away from the foundation, not toward it. Our post on drainage for walkways, patios and driveways explains how that is built.

Gravel for drainage around a house

A strip of stone along the foundation looks tidy and keeps rain from splashing mud on the siding. It does not move water by itself. If the soil under the stone slopes toward the house, the stone simply lets water soak down along the wall faster. Use clean stone over soil that has been graded away from the house, and don't rely on it to fix a wet basement.

3. Catch groundwater before it reaches the house

When a house sits below a slope, water moving through the ground can reach the foundation even when the roof water is handled. A French drain or curtain drain, a trench with perforated pipe in washed stone placed uphill of the house, intercepts that water and carries it to daylight or a dry well. Our post on dry wells versus French drains explains which fits which problem.

4. The basement footing drain

Many basements have a footing drain: a perforated pipe laid in stone along the outside base of the foundation when the house was built. It collects groundwater at the footing and carries it to daylight, a dry well or a sump pit. Very old houses with stone foundations often have none.

Signs of a clogged footing drain

• Water comes in at the joint where the wall meets the floor, along long stretches of the basement rather than one spot.
• The drain outlet in the yard never runs, even after long rain.
• The outlet is buried, crushed, or full of roots and soil.
• The basement started taking water years after the house was built, with no change in grading or downspouts.

How a footing drain is checked and cleared

Start by finding the outlet and making sure it is open. If there is a cleanout, a drain service can run a camera through the pipe to see where it is blocked or broken, and flush it with a water jetter. When the pipe has collapsed or was never wrapped to keep silt out, the only real fix is to dig along the foundation and replace it. That is a large job, and it is usually done together with repairs to the outside of the wall and damp-proofing while the wall is exposed.

Gerrior's drainage work starts outside: grading, drains, dry wells and the foundation masonry. If the basement may also need an interior perimeter drain or sump pump, ask us whether that is part of your project.

Massachusetts conditions that make it worse

• Freeze-thaw. Wet soil that freezes against a foundation expands and pushes on the wall every winter.
• Spring groundwater. Snowmelt and spring rain raise the water table, which is why many basements only leak in March and April.
• Clay, fill and ledge. Slow-draining soil around Woburn and the nearby towns keeps water against the wall longer.

For water collecting in a narrow side yard, see drain on the side of the house. For a flooded basement window well, see window well drainage. For yard-wide problems, see residential drainage systems.

Any of the digging above needs a Dig Safe notice first. Massachusetts law requires at least 72 hours, not counting weekends and legal holidays (Dig Safe FAQ).

When to call a contractor

Call when water is getting into the basement after you have handled the downspouts, when the fix needs digging or a dry well, or when you see cracks, crumbling mortar or white mineral deposits on the foundation. Gerrior installs French drains, dry wells, underground downspout piping and regrading, and repairs the foundation masonry. Owner Joseph Gerrior oversees the work. See our foundation and drainage repair page, and if water is already coming through the wall, our post on foundation leak repair. A Reading customer wrote about a drainage job we did:

"Joe and his crew just finished up a drainage job for us. They were on time, great to work with (as usual) and the guys always friendly. They were very careful in the yard and Joe was excellent with the little excavator." Larry P., Reading, MA

Common questions

How far should downspouts drain from the house?

Far enough that the water lands on ground sloping away from the house and doesn't run back. On small lots that usually means a buried pipe to daylight or a dry well rather than a short extension.

Is gravel or mulch better against the foundation?

Neither fixes drainage. What matters is the slope of the soil underneath. Keep any mulch thin and below the siding.

Can a clogged footing drain be cleared without digging?

Sometimes, if there is an outlet or cleanout to work from and the pipe is not collapsed. A camera inspection tells you which.

Do I need a sump pump?

Possibly, if groundwater rises above the basement floor. That is a question for a waterproofing contractor. Fixing the outside drainage first often reduces how much a sump has to do.

If your basement takes water after rain, we can look at the gutters, grading and foundation together and tell you which fix comes first. Gerrior Masonry & Landscape Construction Corp. is a family-owned company in Woburn, MA, with over 30 years in masonry and drainage work. We are fully insured, our work is guaranteed, and estimates are free. Call (781) 933-4157 or request a free estimate.