How much does it cost to fix negative grading?

Is it expensive to fix negative grading around a house?

Fixing negative grading means regrading the soil around a foundation, which costs $835 to $3,000 at national prices, according to Lawn Love's grading cost guide. Ask the seller to correct it before closing, priced by a landscaping or drainage contractor's written bid.

Key takeaways

• The target slope is a drop of at least 6 inches over the first 10 feet from the foundation.
• Regrading one 40-foot wall with new sod runs $1,195 to $3,720 at national rates, or $1,595 to $6,720 with a French drain.
• If the lot is too tight or steep for that slope, the building code allows a drain or swale instead.

What does negative grading mean, and is it serious?

Negative grading means the soil slopes toward the house instead of away from it. The home inspector trade group InterNACHI (International Association of Certified Home Inspectors) explains the drainage section of the International Residential Code (IRC), R401.3, in its foundation code guide. The ground "should slope away from the building, dropping at least 6 inches within the first 10 feet." A report flags negative grading when the slope runs the other way.

The risk is water at the foundation. InterNACHI's grading article warns that the water "might pool against your foundation, seep into your basement, or saturate the soil until your foundation starts shifting and cracking." It names downspouts too: dumping water "right next to your foundation" is "creating your own flooding problem."

So read the rest of the report for the same wall. If it also notes cracks, water stains or dampness there, get a structural engineer's evaluation before your deadline.

What does it cost to regrade around a house?

The sources below disagree mostly on scope. As White Shovel, a grading contractor, puts it, one side of a house costs less than fixing the slope all the way around.

Here is one finding priced with Lawn Love's national figures. Say the inspector flags soil sloping toward the back wall, and the contractor regrades a strip 40 feet long and 10 feet out from the house.

• Regrade the strip: Lawn Love's foundation row in the table.
• New sod over 400 square feet at $0.90 to $1.80 per square foot: 400 x $0.90 = $360, and 400 x $1.80 = $720.
• Regrade plus sod: $835 + $360 = $1,195, and $3,000 + $720 = $3,720.
• If regrading alone can't clear the water, add a French drain along the same 40 feet: 40 x $10 = $400, and 40 x $75 = $3,000.
• Total with the drain: $1,195 + $400 = $1,595, and $3,720 + $3,000 = $6,720.
• If your city requires a grading permit, add it. Lawn Love puts the average at $150 to $485.

Your contractor's written bid replaces all of this with one number for your yard. Kept prices every line of an inspection report for $79, usually under 4 hours. It marks regrading and drainage correction as a line that needs a contractor's quote, as how Kept prices a repair explains.

How do you fix negative grading?

To fix negative grading, a contractor builds the slope back with fill dirt, compacts it, and tops it with soil that grows grass. White Shovel warns that "not compacting soil leads to settling over time," which brings the low spots back.

When the lot can't take the full slope, the IRC allows another route. InterNACHI's code guide says "drains or swales can be installed to redirect water away from the structure." Options include:

• French drain: a gravel-filled trench with a pipe that carries water away.
• Catch basin: a grated box at the yard's low point that feeds a pipe.
• Downspout extensions: InterNACHI's advice to homeowners is to "extend downspouts away from the foundation."

Who can price it before my deadline?

Call a landscaping or drainage contractor who does grading. Ask for a written bid that names the area, the fill and topsoil, any drain, and any permit. If the report shows cracks or water on that wall, book the structural engineer first, since that answer can change the whole request.

How to get repair estimates during the inspection period covers getting a visit booked and a figure in hand fast.

What do I ask the seller for?

Ask for the repair or a credit, as one line with its own number:

• Regrade the soil at the rear foundation to slope away from the house, per a drainage contractor's written bid.
• Add a drain where the contractor finds the lot too tight to regrade, per the same bid.

If the seller does the work, ask for the contractor's invoice, and the permit if one was pulled, before closing. At your final walkthrough, check that the soil now slopes away from that wall. White Shovel puts a medium project around a foundation at 3 to 5 days and notes that rain delays grading, so ask early.

What to ask for after a home inspection shows how these lines sit with the rest of your list. The buyer repair request letter template gives the wording around them.

What if the seller won't fix it?

Ask for a credit for the bid total, and hire the work yourself after closing. Your contract sets the dates and terms for the request, so confirm them with your agent. If the foundation side can't be priced before your deadline, read when to walk away after a home inspection.

What kind of dirt is used to regrade a yard?

Regrading uses two kinds of dirt. White Shovel describes fill dirt as the base that "fills in holes and creates the right slope." Topsoil goes on top after grading so grass and plants grow. Your contractor's bid should list both.

Can I regrade the yard myself after closing?

Not the part against the house. White Shovel says to hire a professional "for projects larger than a few hundred square feet or any work near your foundation." Lawn Love calls grading "the type of complex work you should leave to professionals." Price it as contractor work in your request.

How do I know what the rest of my report is worth?

Price every line before your deadline, not just the yard. Spend your bid time on the lines that need a trade, like this one, and get a priced list for the rest.

If negative grading is one line among many on your report, upload it to Kept and spend your remaining days on the bids that need a contractor.

Sources

• InterNACHI, Foundation Fundamentals: Inspecting Load Paths and Water Paths (IRC R401.2 and R401.3)
• InterNACHI, The Hidden Threat in Your Yard: How Poor Grading and Landscaping Can Flood Your Foundation
• Lawn Love, How Much Does Land Grading Cost?
• Yelp Cost Guides, Landscape Grading and Resloping Cost
• White Shovel, Landscape Grading and Drainage Costs