The water comes back every storm. So does the guy who never finished.

Standing water and a wet basement are a grading and discharge problem before they are a French drain problem. We diagnose where the water actually goes, price the fix as one fixed number, and finish the scope we signed.

French Drain Around a Foundation in Edwardsville, IL

Direct answer: A French drain around a foundation — a perimeter or footing drain — sits at the base of the wall and intercepts water before it can build pressure against it. That is structurally the right place to stop water, and it is also the most expensive place to work, because reaching it means excavating to the footing. Exhaust downspout discharge and grading first; they solve a large share of the same symptoms for a fraction of the cost.

What a French drain around a foundation involves

The trench follows the wall down to the footing, which on a full basement means several feet of excavation against the structure. Perforated pipe is laid in washed stone at that depth, pitched continuously to a discharge point, and the wall is usually damp-proofed or membraned while it is exposed — because it never will be again cheaply.

Everything above the trench line has to come out and go back: shrubs, beds, walkways, sometimes a patio edge or a section of drive. That restoration is a real cost and it belongs on the quote as its own line rather than folded into a per-foot figure.

Perimeter drain cost by approach

Approach	Cost range	Timeline
Exterior footing drain, full perimeter	$95 – $180 / linear foot	5 – 10 days
Exterior drain, one problem wall	$4,500 – $12,000	3 – 5 days
Interior perimeter drain + sump	$60 – $110 / linear foot	3 – 5 days
Wall membrane while excavated	add $12 – $25 / linear foot	concurrent

Edwardsville and Madison County. Landscaping and hardscape restoration quoted separately.

Interior versus exterior, and why the cheaper one is common

An interior perimeter drain does a related job from inside: a channel cut in the slab at the footing, pipe in stone, run to a sump pit. It manages water that has already reached the foundation rather than intercepting it beforehand, which is less ideal structurally and dramatically less disruptive.

That trade-off is why interior systems are quoted more often here. It is a legitimate choice, not a shortcut — but it should be presented as a choice, with the reason stated, rather than as the only option.

Before you commit to excavating a foundation

Confirm the water is actually reaching the footing. A basement that is dry for months and wet within hours of heavy rain is usually being fed by surface water — downspouts at the wall, ground pitched back toward the house — and those cost hundreds to correct rather than thousands.

A perimeter drain is the right purchase for hydrostatic pressure from a seasonally high water table, which shows up as water arriving regardless of recent rainfall. Establishing which pattern you have is the single highest-leverage step in this whole decision.

French drain around a foundation: questions

How much does a French drain around a foundation cost?

An exterior footing drain around a full perimeter typically runs $95 to $180 per linear foot in this area because of the excavation depth and the restoration involved. A single problem wall is often $4,500 to $12,000. An interior perimeter drain tied to a sump is less disruptive at $60 to $110 per linear foot.

Should the drain go inside or outside the foundation?

Outside stops water before it reaches the wall, which is structurally preferable, but it means excavating to the footing and restoring everything above the trench. Inside manages water that has already arrived and is far less disruptive. Both are legitimate; the choice should be explained rather than assumed by whoever is quoting.

Do I need a perimeter drain or just better grading?

If the basement is dry for long stretches and only takes water within hours of a storm, surface water is the likely cause and grading plus downspout discharge should be exhausted first — they cost hundreds rather than thousands. A perimeter drain is the right answer for water arriving regardless of rainfall, which indicates a high water table.

How deep does a foundation French drain need to be?

At the footing, which on a full basement means several feet down against the wall. That depth is the point of the system: a drain installed higher intercepts some surface water but leaves the hydrostatic pressure at the base of the wall untouched, which is the pressure that actually drives water through it.

What we put in writing before anyone digs

Fixed-price written quote before we break ground. Trenching turns up surprises; the price does not move because of them unless you approve a change order in writing first.
Zero-obligation site visit. If the honest answer is that the water is doing what water should do and you do not need a drain, that is the answer you get, in writing, at no cost.
The diagnosis names where the water comes from before it names the product. Grading, downspout discharge, and the water table get checked first; a French drain is a conclusion, not an opening bid.
Full-width trench, wrapped stone, and rigid perforated pipe as standard. We do not install narrow single-pipe trenches or pre-socked corrugated sections, because those are the installs that fail in year three.
Itemized scope showing linear feet, trench depth, stone volume, and discharge point as separate lines. No lump-sum 'drainage work.'
A named discharge point on the plan, with the permit or easement dependency listed separately so you can see which clocks we do not control.
If the system does not move water after the first heavy rain, we come back and correct it at our cost, not yours.