# Foundation Drainage Baton Rouge | French Drains, Grading, Downspouts > Foundation drainage in Baton Rouge: French drains, regrading and downspout lines that keep clay soil under your slab at steady moisture. Free evaluation. URL: https://foundationrepairbatonrougelouisiana.com/foundation-drainage/ ![Foundation Drainage in progress at a Baton Rouge home](https://foundationrepairbatonrougelouisiana.com/images/hero-foundation-drainage-french-drain-trench-baton-rouge.webp) # Foundation Drainage in Baton Rouge French drains, regrading and buried downspout lines that stop water pooling against the slab — often the cheapest foundation repair there is. Typical range: **$1,500–$12,000**. [Call (225) 635-8757](tel:+12256358757) [Book a free evaluation](https://foundationrepairbatonrougelouisiana.com/contact/) - Free on-site evaluation - Written per-piling price - Same-day callback Get a Free Quote Free on-site evaluation · written price - 20 years of industry experience - Written per-piling pricing - Same-day callback - Serving 5 parishes Last updated: September 22, 2026 [Foundation Repair Baton Rouge](https://foundationrepairbatonrougelouisiana.com/) is a foundation repair company with 20 years of industry experience, serving Baton Rouge and the Capital Region, and foundation drainage is the repair we recommend most often before — or instead of — pilings. Baton Rouge gets around 60 inches of rain a year. When a downspout empties at the corner of your house or the yard slopes toward the slab, that side stays wetter than the rest. Clay that’s wet swells; when August dries it out, it shrinks. The edge of the slab rides up and down with it. Foundation drainage typically costs **$1,500–$12,000**. Tying downspouts into buried solid lines starts around **$1,000**; perimeter French drains and regrading cost more. ## What we do on the first visit We watch where the water goes. Ideally that’s during a rain; otherwise a hose test on the roof valleys and downspouts shows us. We look for splash-back on the brick, erosion at the slab edge, low spots that hold water, sprinkler heads spraying the foundation and beds mounded against the house. You get a drawing of what goes where, with prices, and our honest view of whether drainage alone will stop the movement. ## Why drainage matters so much here Even soil moisture is what keeps a slab stable. The center of the slab, under the house, stays fairly constant. The perimeter doesn’t. The more water you add to one side — from a downspout, a leaky hose bib, or a yard graded the wrong way — the bigger the swing between wet and dry, and the more that side moves. On the pier and beam side, water pooling under the house softens the soil under pier footings and fuels rot in the crawl space. ## What we install - **Downspout lines:** solid PVC pipe buried from each downspout to a discharge point well away from the house, sized for the roof area feeding it. - **French drains:** perforated pipe in washed gravel wrapped in filter fabric, where runoff or groundwater collects. - **Regrading:** soil shaped so it falls away from the foundation, and beds pulled back from the slab edge. - **Emitters:** pop-up emitters at the ends of lines so water discharges in the lawn or at the street, not in a puddle. Every line gets a flow test before we backfill. ## When drainage isn’t enough If the laser survey shows one side of the house already more than about an inch low, drainage alone won’t lift it. In that case we quote [slab foundation repair](https://foundationrepairbatonrougelouisiana.com/slab-foundation-repair/) and drainage together, because pilings under a house with the same water problem are fighting uphill. ## What's included - Walk-around during rain or with a hose test - Map of downspouts, low spots and discharge points - Written drainage plan with line routes - Downspouts tied into buried solid lines - French drains where groundwater or runoff collects - Regrading so soil falls away from the slab - Discharge to the street, ditch or daylight - Final flow test ## Drainage options compared DIY / patch it Cheapest crew Done properly What it does Moves water a few feet Surface pipe or splash blocks Buried lines to daylight, regraded soil Mower-proof No No Yes — buried Handles heavy rain No Partly Sized for roof area Typical cost $20–$100 $200–$800 $1.5k–$12k ## Related resources - [How Much Does Foundation Repair Cost in Baton Rouge? (2026)](https://foundationrepairbatonrougelouisiana.com/guide/foundation-repair-cost-baton-rouge/) - [9 Signs of Foundation Problems in Baton Rouge Homes](https://foundationrepairbatonrougelouisiana.com/guide/signs-of-foundation-problems/) - [Foundation Damage After a Flood — What to Look For](https://foundationrepairbatonrougelouisiana.com/guide/foundation-damage-after-flood/) Talk to a person Free on-site evaluation, written price per piling. [(225) 635-8757](tel:+12256358757) [Book online](#service-form) Mon–Fri 7:00 AM–6:00 PM · Sat 8:00 AM–1:00 PM Methods & standards - Solid PVC downspout extensions to daylight - Perforated pipe in washed gravel + fabric - Minimum 1% slope on drain lines - Grade falling away from foundation - Pop-up emitters at discharge - LSLBC-registered contracting Price guide $1,500–$12,000 Downspout lines from ~$1,000; perimeter French drains higher [Estimate my house](https://foundationrepairbatonrougelouisiana.com/tools/foundation-repair-cost-estimator/) The process ## How foundation drainage works, step by step 1. 1 ### Watch the water We trace where roof and yard water go, ideally during rain or with a hose test. 2. 2 ### Plan the routes A drawing of each line, its slope and where it discharges. 3. 3 ### Install Trenches, pipe, gravel and fabric; downspouts tied in; soil regraded. 4. 4 ### Flow test Water through every line to confirm it discharges where it should. ## What the work looks like Illustrative photos of the methods described on this page. [Foundation Repair Baton Rouge Call us to schedule a free foundation drainage estimate Free laser survey. Written plan with unit prices. (225) 635-8757](tel:+12256358757) ## Foundation Drainage FAQ ### Can drainage really fix a foundation problem? It can stop one. Water discharged against one side of a slab keeps that side's clay wetter, so it swells and shrinks more than the rest. Moving the water away evens out soil moisture. If the slab has already dropped more than about an inch, you'll need pilings as well — drainage keeps them from fighting the same water. ### What is a French drain? A trench with perforated pipe bedded in gravel and wrapped in filter fabric that collects groundwater and surface water and carries it to a discharge point. It's different from a solid downspout line, which just moves roof water. ### Should a French drain go right against the foundation? Usually not right against it. On slab homes we generally keep perimeter drains a short distance out so we don't disturb the soil supporting the beam, and we never let a drain discharge near the slab. ### Where does the water go? To the street, a roadside ditch, or a low point on your lot far enough from the house — with a pop-up emitter at the end. We check local rules about discharging to the street. ### Is the foundation evaluation really free? Yes. The on-site evaluation, laser elevation survey and written plan cost nothing and carry no obligation. If the numbers say your house is within normal tolerance, we tell you that and leave the readings with you. An independent engineer's report, when a lender or buyer requires one, is billed by the engineer — typically $500–$2,000. ## Related services [Slab Foundation RepairPressed concrete pilings driven to refusal under a settling slab, then the house is lifted back toward level and re-measured.](https://foundationrepairbatonrougelouisiana.com/slab-foundation-repair/) [Concrete LevelingRaising sunken patios, walks and garage slabs with mudjacking or polyurethane foam — a fraction of the cost of tear-out.](https://foundationrepairbatonrougelouisiana.com/concrete-leveling/) [Crawl Space RepairVapor barriers, drainage and supplemental supports under raised homes — stopping the humidity that rots sills and joists.](https://foundationrepairbatonrougelouisiana.com/crawl-space-repair/) Book a free foundation drainage evaluation Start with clear answers from an experienced team. Tell us what you are seeing, and we will call back the same business day to arrange your free evaluation. Faster by phone: [(225) 635-8757](tel:+12256358757)