Florida-wide consultation Pensacola to the Keys · no-cost assessment
Florida-wide · 60-second estimate · Consultation & assessment, no cost

Know what your seawall actually costs before you call a contractor.

A free tool built for Florida waterfront homeowners. Get a real, zip-level replacement price — homeowners pay an average of $800–$900 per linear foot or more — plus a 12-point contractor punch list, and an honest look at the other property factors (stormwater, irrigation, drainage) that often drive the soil loss behind the wall in the first place, causing seawall failure.

$800–$900+average per linear foot, FL replacement
4–8 monthstypical replacement timeline
0.5–2 in/yrsoil erosion — the #1 cause of failure
A free homeowner tool, sponsored by Gulf Coast Soil & Seawall Doctors · A Florida solutions-based company — we help you choose the right path, even if that path isn't us
Step 1 of 3

Your project, priced honestly.

Pricing built from publicly available 2025–2026 Florida residential contractor quote data, adjusted to your zip code in real time. This tool is informational — final pricing always requires an on-site assessment.

Many Florida walls labeled “failing” are actually minor-to-moderate. Before committing to full replacement, it's worth getting a second opinion on whether soil stabilization or partial repair could extend the wall you already own.
Enter a 5-digit FL ZIP
80 ft
4 ft
How deep the water is against your wall at high tide — the submerged portion the new panels have to span. 0–2 ft = canal/lake; 3–5 ft = typical residential; 6–8 ft = Intracoastal/deep canal.
3 ft
How far the cap stands above the water at high tide. Florida code often requires the cap 2–4 ft above mean high water.
Total exposed wall height · mudline to top of cap 7 ft The figure engineers and contractors use to spec embedment depth, panel length, and tiebacks. (Embedment below mudline adds another 8–12 ft.)
Land vs. water access is one of the biggest cost drivers. Barge work runs 30–40% more than yard access per industry data (Pearce Marine, Truline).
Many seawall replacements require pulling the dock and lift first. Demo, haul-off, and disposal are billed separately.
Site conditions (optional — improves accuracy)
Hiring a contractor — homeowner punch list

12 things to confirm before you sign a replacement contract.

Florida seawall work is permit-heavy, engineering-heavy, and easy to under-spec. Walk through this list with every bidder. If a contractor can't answer plainly, that's your answer.

  1. 01

    Licensing & insurance

    Florida marine-contractor license (CGC or specialty), active general liability, and current workers' comp. Ask for certificates listing you as additional insured before mobilization.

  2. 02

    Engineer-sealed plans

    Signed and sealed drawings from a Florida-licensed PE — sheet type, embedment depth, cap dimensions, reinforcing, tieback design, anchor specs. No "we'll figure it out on site."

  3. 03

    Geotechnical report

    Many FL municipalities require a soil report before issuing a permit. Confirm soundings have been done and the engineer designed to those numbers, not a generic profile.

  4. 04

    Permits in hand before mobilization

    FDEP (or SPGP), USACE (Army Corps), and county/city — all confirmed and issued before any equipment hits your yard. Get copies. Check the 18-inch waterward limit on replacement walls (SPGP VI-R1).

  5. 05

    Defined scope & materials

    The contract should list sheet type and manufacturer, cap dimensions and rebar, anchor/tieback spacing and length, riprap size, and filter fabric spec. Vague scope = expensive change orders.

  6. 06

    What's included (and what's not)

    Survey, permit fees, mobilization, demo, disposal, site restoration (sod, irrigation, hardscape repair), dewatering, and as-built. Force the items not included into writing too.

  7. 07

    Milestone-based payment draws

    Draws tied to inspection milestones (mobilization, panels set, cap poured, tiebacks installed, restoration complete). Each draw paired with a partial lien release from the contractor and subs.

  8. 08

    Written change-order process

    No verbal upcharges. Every scope change in writing with unit pricing the contractor commits to up front (per linear foot, per anchor, per yard of riprap). Sign before work continues.

  9. 09

    Warranty terms — in writing

    The longest warranty most Florida marine contractors offer is 1 year on craftsmanship/workmanship. A “limited lifetime” warranty on vinyl sheet pile or composite is a material warranty from the manufacturer — it covers the polymer not degrading. It does not cover the wall failing. Ask for separate written warranties on the cap, panels, tiebacks, workmanship, and erosion behind the wall — with year terms and exclusions. Almost no marine contractor warrants against erosion. Confirm transferability if you sell.

  10. 10

    References with photos

    Three recent residential jobs in your county. Drive by if you can. Ask the homeowners about timeline accuracy, change orders, restoration quality, and how the contractor handled punch-list items.

  11. 11

    As-built survey at closeout

    A licensed surveyor or PE letter confirming the wall was built to the sealed plans and within permit limits. You'll want this on file for resale, insurance, and any future permit work.

  12. 12

    Dry-season scheduling & realistic lead times

    Florida wet-season work loses days to weather. Honest bidders schedule major sheet-pile work for dry months (typically Nov–May) and pad timelines accordingly. Distrust "we'll be done in 3 weeks" on a full replacement.

Take this with you.

Get the punch list emailed and texted to you before your next contractor meeting. Quick form below — we'll send the checklist plus your zip-code estimate, and we won't share your info with anyone.

The truth about seawall failure

Your wall isn't failing. The soil behind it is.

Replacement is sometimes the right answer — but the wall panels themselves usually have decades of life left. The real enemy — the one a brand-new $80k wall won't fix — is soil erosion behind the wall. Here's what every Florida waterfront owner needs to know before they sign a replacement contract.

Behind the wall
where it starts

Sediment loss and sinkholes are the warning signs

Massachusetts coastal management guidance (Mass.gov StormSmart Fact Sheet 7) is blunt: signs that overland runoff or wave overtopping has caused erosion around seawalls include "erosion of sediment behind seawalls" and "sinkholes behind structures." The wall can look plumb while the backfill quietly leaves through cap joints, panel seams, and tidal pumping.

#1
cause of failure

Erosion — not the wall — is what fails first

Per Mass.gov, soil loss behind a seawall "can compromise the integrity of the structure and potentially cause it to fail." Hairline cracks become voids. Voids become sinkholes. Sinkholes pull the wall outward, and then the wall finally fails. By the time you see a leaning panel, the soil has been leaving for years — often through a problem on the landward side of the wall.

Day 1
it starts

Drainage pressure matters as much as the wall

Mass.gov recommends that seawall repair or reconstruction projects "include improvements to the drainage system to prevent pressure from building up behind the wall due to wave overtopping or ponding of rainwater. This pressure is one potential cause for structural failure." Filter fabric and weep holes slow soil migration, but they can't fix the upstream drivers — rooftop runoff, irrigation overspray, and impervious surfaces all upstream of your wall.

The honest takeaway: Full replacement is the right call for many walls — leaning panels, failed tiebacks, structural compromise. But if your wall is plumb and panels are aligned, it's worth asking a marine engineer whether soil stabilization and property-side drainage corrections could address the actual failure mechanism (erosion behind the wall) before you commit to a tear-out. Two opinions cost nothing.
Other erosion drivers on your property

Your wall isn't the whole story. Look uphill.

A new $80,000 seawall can't fix a downspout pointed at it, an irrigation zone overspraying the cap, or a driveway grading runoff toward the water. These are the property-side drivers that quietly erode backfill behind even a healthy wall. We look at all of them during an inspection — even when the wall itself is fine.

Downspouts & roof runoff

University of Wisconsin–Stevens Point's waterfront erosion guide notes that "runoff from roofs frequently creates erosion. Many of the small gullies that lead to the lake begin where water falls from rooftops." For a Florida waterfront home, that gully runs straight to your seawall.

The fix: Extend downspouts to a rain barrel, dry well, or infiltration area at least 10 feet from the wall. Never aim a downspout at the cap.

Source: UW–Stevens Point Lakes Program

Sprinkler overspray near the wall

Irvine Ranch Water District guidance is direct: "overhead irrigation should not be used in planting areas directly adjacent to streets, driveways and waterways." Yet most Florida turf irrigation systems were installed years ago with full-circle heads that throw water right over the seawall cap.

The fix: Swap full-circle heads near the wall for half- or quarter-pattern heads. Audit head alignment after every storm or mower strike. Move thirsty plantings 3+ feet back from the cap.

Source: Irvine Ranch Water District

Irrigation runtime on slopes & clay

TLC Incorporated's erosion guide cuts to the cause: "irrigation systems don't cause erosion randomly. They cause erosion when they're applying water faster than your soil can absorb it." On a Florida lot with clay-heavy fill behind the wall, two heads overlapping double the application rate — and the excess runs straight toward the water.

The fix: Use cycle-and-soak programming (multiple short cycles instead of one long run). Check application rates per zone. Lower precipitation rates near the wall.

Source: TLC Incorporated

Impervious surfaces & lot grading

UW–Stevens Point's guidance applies directly to canal-front Florida lots: "impervious surfaces like roofs and driveways can make the problem worse because they don't allow water to soak into the ground, creating more runoff. Slope driveways, sidewalks, and other nonporous surfaces so they drain away from the lake or river."

The fix: Re-grade so hardscape sheds water toward yard infiltration areas — not toward the seawall. Add a permeable strip or swale before the cap. Direct pool deck and patio drainage upland.

Source: UW–Stevens Point

Hydrostatic pressure behind the wall

Mass.gov calls it out: "pressure building up behind the wall due to wave overtopping or ponding of rainwater … is one potential cause for structural failure." Every clogged weep hole and undersized drain converts your wall into a swimming pool retaining wall.

The fix: Pressure-wash weep holes annually. Verify the back-of-wall drainage system carries water away — not just down. Repair sinkholes or ponding behind the cap promptly.

Source: Massachusetts StormSmart Properties

Neighbor drainage & shared lot lines

Per Mass.gov: "if overland runoff is causing erosion, this runoff should be reduced or redirected." On Florida canal lots, that runoff often originates next door — a graded driveway, an unbuffered roof, an irrigation system overspraying onto your turf. Erosion behind your wall can be a neighbor problem first.

The fix: Walk the lot line during a heavy rain. Look for sheet flow crossing onto your property. Add a small berm, swale, or rain garden along the line to intercept it before it reaches the cap.

Source: Massachusetts StormSmart Properties

Want an honest look at all of this? A no-obligation consultation — virtual, on-site, or both — covers the wall, the yard, the drainage, and the irrigation, not just the panels. We can start over video with you showing us the wall on your phone, then come out in person if it’s worth a closer look. You’ll get a written assessment whether or not you hire anyone.

Schedule a no-obligation consultation →

No used-car-lot routine, no “let me go talk to my manager” theatrics, no upsell to a $60k replacement you don’t need. We’ll point you to the fix that fits — use us, use someone else, or do nothing at all.

What replacement actually looks like

Months of barges, fences, and a backyard you can't use.

Before you commit to a replacement quote, this is the reality you're signing up for: a working-equipment job site in your backyard for 4–8 months, blocked water access, fenced-off patio, torn-up sod, and broken irrigation. Knowing what's coming helps you ask the right questions — and decide whether a less-invasive option could buy you years before you commit.

Either way, no storm-chaser roofer routine — we’ll tell you straight whether your wall actually needs replacing or just a soil fix underneath it.

Proudly serving Florida waterfront homeowners

A solutions-based approach — not a sales pitch.

Gulf Coast Soil & Seawall Doctors sponsors this free tool because we believe an informed Florida homeowner makes a better decision — whether that decision is to hire us, hire someone else, or wait and monitor. We work across the full range of waterfront solutions: stormwater redirection, drainage and sprinkler corrections, soil stabilization and void-fill injection, partial repair, and full marine-contractor referrals when full replacement is the right call. Talk to us. We'll help you sort the options, no obligation.

01

Comprehensive Inspection

Our specialists assess your property for damage, wear, or structural concerns, then develop a customized plan based on the findings — at no cost to you.

02

Advanced Repair

Our skilled technicians use NCFI Geotechnical polyurethane to repair concrete and seawall issues — cracks, erosion, and separation — for long-lasting protection.

03

Environmentally Friendly

Closed-cell, inert, hydrophobic foam. We prioritize coastal preservation, using eco-friendly methods that safeguard shorelines and minimize environmental impact.

04

Expert Project Management

Our committed project managers ensure seamless seawall and soil repair with clear communication, timely progress, and minimal property disruption.

05

Ongoing Maintenance

Optimize your seawall's durability with tailored maintenance from Gulf Coast Soil and Seawall Doctors — ensuring longevity and customer satisfaction.

06

Concrete Lifting & Leveling

Foundation stabilization, sinking driveway repair, and pool deck leveling — enhancing infrastructure durability and mitigating erosion risks for the long term.

Pensacola seawall with soil void — real Gulf Coast Soil & Seawall Doctors project Pensacola, FL · Real project
Recent work

This is what soil loss looks like.

You can see the seawall is fine — it's the soil behind it that's washing out through hairline cracks at the cap joints. Six hours of NCFI Terra-Lok injection sealed the joints, stabilized the soil, and saved this homeowner from a $34,000 replacement quote.

See the full case study →
What you're actually signing up for

The real timeline from "I need a seawall" to splash day.

Most homeowners don't know there are three separate regulators involved before a single panel goes in the ground. Here's the unvarnished sequence.

  1. 1
    Week 1–2

    Inspection & engineering

    A marine engineer inspects the wall (often with a dive survey), assesses soil conditions, and produces signed and sealed drawings. $600–$2,500 for inspection, $2,000–$5,000 for engineering.

  2. 2
    Month 1–3

    FDEP Environmental Resource Permit

    Florida Department of Environmental Protection reviews impacts to submerged lands, water quality, and seagrass. Most residential seawalls qualify for a Noticed General Permit (30–60 days); complex sites need a full Individual ERP (60–120 days).

  3. 3
    Month 2–6

    U.S. Army Corps of Engineers

    Federal authorization is separate from FDEP and is required for almost every coastal project. A Nationwide Permit runs 30–60 days; an Individual Permit can take 6–18 months if your site has manatee, sea turtle, or critical habitat overlap.

  4. 4
    Month 3–6

    County & municipal permits

    Building permit, zoning review, HOA approval if applicable, and (for some counties) submerged lands consent. Pensacola/Escambia, Lee, Pinellas, and Miami-Dade each have their own quirks.

  5. 5
    Month 4–8

    Construction

    Vinyl: 4–6 weeks. Concrete: 6–10 weeks. That includes demo of the old wall, sheet/panel driving, tieback installation, backfill, and concrete cap pour and cure. Longer walls (150+ ft), tall exposure (8’+), or leaning walls add 1–3 weeks. Marketing pages quoting “1–2 weeks” are usually counting only the panel-driving phase — not demo, tiebacks, backfill, or cap cure.

  6. 6
    Month 5–9

    Final inspection & site restoration

    Sod, landscaping, dock reattachment, and as-built drawings filed with the county. Now you can splash the boat.

Gulf Coast Soil and Seawall Doctors injection job in progress
Or skip the entire timeline above

If injection is the right call for your wall, the whole job is typically 1–2 days.

No FDEP permit. No Army Corps permit. No demo. No site restoration. Just precision drilling, NCFI polyurethane injection, and a water-tight barrier behind your wall. It's not right for every wall — but for the ones it fits, it's a meaningful alternative worth pricing out.

Learn more about injection →
An alternative worth considering

The repair that takes your existing investment and extends its life.

Some "failing" seawalls aren't structurally failing — the wall itself is fine, but the soil behind it is washing out at 0.5–2 inches per year. When that's the actual mechanism, NCFI polyurethane injection can seal the soil loss and stabilize the backfill, extending the useful life of the wall you already own. It's not the right tool for every wall — but when it fits, it's worth pricing alongside replacement.

Injection may be worth a conversation if you see:

  • Sinkholes or depressions in your yard near the wall
  • Sod that keeps dying or settling along the seawall line
  • Water seeping through cracks at low tide
  • Hairline-to-medium cracks but the wall is still plumb
  • Joints separating but panels still aligned
  • An aging wall that still has useful structural life

Full replacement is the right call if:

  • The wall is visibly leaning more than 3"
  • Multiple panels are bowed or rotated
  • Tiebacks are widely rusted through
  • Rebar is exposed across multiple panels
  • The cap has separated from the wall
The warranty truth nobody tells homeowners

You’re going to want the warranty — just not the one they’re selling.

Three warranty words get mixed up in seawall sales conversations: material, workmanship, and erosion. Only one of them describes the thing that actually fails your wall.

Workmanship / craftsmanship

1 year

That’s the longest most Florida marine contractors will put in writing.

Standard residential seawall contracts in Florida warrant the labor and installation for 1 year from substantial completion. After that, the contractor is off the hook for craftsmanship issues. Some larger firms will extend to 2–3 years on tiebacks or cap work — but the 1-year default is the market.

Material (“limited lifetime”)

The panel only

Lifetime on vinyl or composite is a manufacturer promise about the polymer — not the wall.

When a vinyl sheet pile or composite seawall brochure says “limited lifetime warranty,” that is a material warranty from the panel manufacturer. It warrants that the polymer panel itself will not biodegrade, delaminate, or chemically break down. That is an easy promise to make: composite plastics aren’t the reason Florida seawalls fail. The cap can crack, the tiebacks can fail, and the soil behind it can wash out completely — the panel will still technically be “warrantied.”

Erosion

Nobody warrants it. We do.

The actual failure mode — the one engineers know is coming — is the one almost nobody puts in writing.

Walk every marine contractor in Florida through your wall and ask: “Will you warrant against soil erosion behind the wall?” The answer is almost always no. Erosion is classified as an environmental condition, not a workmanship defect, and it is excluded by name in most contracts. That is the warranty you actually want, because erosion is the failure mode that ends seawalls — not panel breakage.

What we offer instead: a transferable workmanship warranty on the treated soil zone up to 7 years, backed by a product engineered to last a lifetime — the polyurethane itself. The polymer is chemically inert, hydrophobic, and unaffected by saltwater. Properly installed, it’ll outlive all of us. The 7 years is what we’ll put our name on for the install. The lifetime is what the chemistry actually does in the ground.

What the engineers already know

Erosion isn’t a risk in their math — it’s an assumption.

Coastal and geotechnical engineers don’t treat soil loss as a hypothetical. When they spec a seawall’s design life, embedment depth, tieback spacing, and panel section modulus, they are explicitly factoring in active soil erosion, scour at the toe, and settlement of the retained fill over the wall’s service life. Florida-specific design references like FDOT’s Structures Design Manual and standard practice guides like the ASCE Waterfront Facilities Inspection & Assessment manual require engineers to assess scour, settlement, and “loss of backfill” on every inspection — not as edge cases, but as standard service-life inputs.

“The wall is sized for the soil it’s going to have, not the soil it has on day one.”

  • Embedment depth is calculated assuming the seabed in front will scour down 1–3 ft over the wall’s life.
  • Tieback / anchor loads are calculated assuming the retained soil is partially saturated and partially evacuated through the wall over time.
  • Cap reinforcement is sized for differential settlement of the fill behind it — i.e., the engineer is already assuming the soil will subside.

If erosion is built into the engineering math, why is it excluded from every workmanship warranty in the state? Because the contractor isn’t the engineer. The contractor warrants the install. The engineer assumes the erosion. You, the homeowner, get to absorb the gap between those two — unless you address the soil directly. That’s what an erosion warranty is for.

*Our soil-stabilization workmanship warranty is transferable, tied to the treated zone, and runs up to 7 years depending on project conditions. The polyurethane resin itself is engineered to last a lifetime — chemically inert, hydrophobic, and not known to degrade in soil or saltwater. Workmanship warranty subject to written terms, qualifying project conditions, and exclusions for catastrophic events. Ask for the warranty document before signing.

About our geotechnical polyurethanes

Three NCFI systems. One purpose: stop the soil from leaving.

NCFI Geotechnical polyurethane injections are a suite of single or dual component, closed-cell formulations specifically engineered for geotechnical applications. We service waterfront properties statewide — Tampa, the Florida Keys, Jacksonville, Pensacola, Orlando, West Palm Beach, Fort Lauderdale, Miami, and everywhere in between.

Terra-Lok single component polyurethane system

Terra-Lok

Single Component

A suite of single-component, low-viscosity polyurethane formulations with excellent soil permeation. Closed-cell foam encapsulates loose soils to form a solid, water-tight barrier — stopping water intrusion and increasing load-bearing capacity.

  • Seawall void filling & soil stabilization
  • Water-stop sealing behind bulkheads
  • Slab and foundation undersealing
Strata-Fill low exotherm polyurethane system

Strata-Fill

Low Exotherm Dual Component

Dual-component polyurethane formulated for applications requiring low exothermic heat — perfect for filling large voids and cavities, or building many layers quickly, as with pipeline trench breakers, pipe pads, and pillows.

  • Large-volume void filling
  • Pipeline support & encapsulation
  • Multi-layer lift applications
TerraThane dual component polyurethane system

TerraThane

Dual Component

Dual-component systems with a unique formula suitable for a wide range of geotechnical applications — from lifting and undersealing to water stop and void filling. Every batch meets strict testing and quality assurance standards.

  • Concrete lifting & leveling
  • Driveway, sidewalk, pool deck repair
  • Heavy-load slab stabilization
Technical deep-dive

How NCFI polyurethane actually stabilizes your soil.

Most homeowners just want to know does it work and will it last? The short answer is yes — but the long answer involves real chemistry, real ASTM-tested numbers, and a method engineers and permit reviewers can defend. We've broken this section into two layers: a plain-English overview anyone can follow, and a technical appendix with the actual data sheets for engineers, GCs, and anyone who wants to see the math.

01

Liquid goes in

A low-viscosity polyurethane resin (NCFI Terra-Lok 24-120) is injected through small drill holes — typically ⅝" ports spaced every 18–36 inches along the wall. The resin is thinner than water at the time of injection (65–180 cps), so it permeates the loose sand and fills voids the way water would, but in a controlled, targeted pattern.

02

It reacts with moisture in the soil

Single-component polyurethane is hydrophobic and moisture-activated. When it meets the groundwater already in your sand, it expands several times its liquid volume and chemically locks the sand grains together into a single waterproof mass. Reaction is fast — gel in 20–120 seconds, full rise in 1–4 minutes — so the foam doesn't migrate where you don't want it.

03

You're left with a solid block of sand-and-polymer

Once cured (within hours), the treated zone behind your wall is no longer loose, washable sand — it's a permeation-grouted matrix with measured density around 55 pcf and compressive strength of ~2,490 psi in fine sand (NCFI lab data, ASTM D1621). That's stronger than the soil it replaced, and it stops the tidal pumping that was washing the wall out from behind.

Why this actually works for seawalls (not just a foam gimmick)

  • It addresses the failure mode, not the symptom. Most Florida seawalls don't fail because the panels broke — they fail because the soil behind the panels eroded away. Replacing the panels and putting fresh sand behind them just restarts the erosion clock. Sealing the soil-loss pathway stops the cause.
  • It's chemically inert in saltwater. Cured polyurethane is hydrophobic and unaffected by chlorides or tidal cycling. NCFI's own SEVERE Wastewater Analysis (ASTM D-2842) showed 0% compressive-strength loss after exposure (NCFI Terrathane 24-035 TDS).
  • It's a permanent material in a marine environment. Closed-cell content above 94% means the foam doesn't absorb water over time, and the polymer doesn't biodegrade. The treated zone is designed to last for the remaining service life of the seawall itself.
  • It's not magic — it has limits. Polyurethane stabilizes soil and seals leaks. It does not rebuild a leaning wall, replace failed tiebacks, or rebond a separated cap. When those structural failure modes are present, full replacement is genuinely the right call — and we'll tell you so.
Engineering appendix

ASTM-tested data sheets, mix ratios, and field methodology.

For permit reviewers, marine engineers, and GCs evaluating soil-stabilization specs for a Florida residential or condominium project. All values below come from NCFI Geotechnical's published technical data sheets.

Terra-Lok 24-120 Single-component hydrophobic

Low-viscosity, 100%-solids, moisture-cured polyurethane prepolymer designed for soil permeation, void fill, water-stop sealing, and I/I mitigation. Primary system used for seawall void filling and soil stabilization behind bulkheads. Optional Regular Cat (B-24-120) or Fast Cat catalyst accelerates the reaction based on field conditions.

PropertyTest methodMediumResult
DensityASTM D1622Fine sand, 60% solids55 pcf
Compressive strength @ 10%ASTM D1621Fine sand2,490 psi
Compressive modulus @ maxASTM D1621Fine sand1,370 psi
Tensile strengthASTM D638Fine sand130 psi
Shear strengthASTM D273Fine sand550 psi
ElongationASTM D638Fine sand15%
ShrinkageASTM D1042Fine sand< 4.0%

Component viscosity (Brookfield @ 72°F)

ComponentViscositySpecific gravityShelf life
A-24-120 prepolymer120–180 cps1.126 months
A-24-120 LV (low-viscosity)65–75 cps1.106 months
B-24-120 catalyst10–20 cps0.96 months

Reaction profile (selected ratios)

CatalystActivator wt%Cream (s)Gel (s)Rise (s)
Fast Cat1.0%72236
Fast Cat4.0%61120
Regular Cat1.0%20123180
Regular Cat4.0%1796100

Source: NCFI Terra-Lok 24-120 Technical Data Sheet (07/02/2024)

Terrathane 24-035 Dual-component spray hybrid

Two-component, water-blown, MDI-based polyurethane-polyurea hybrid spray system. Used as high-strength backing material for stabilizing masonry surfaces, manhole lining, and pipe/culvert lining. Notable for chemical resistance in aggressive wastewater environments — 0% compressive-strength loss after SEVERE Wastewater Analysis.

PropertyTest method / conditionResult
Free-rise densityASTM D16226–8 pcf
Closed-cell contentNCFI TM-300> 94%
Cream timeReactivity @ 130°F1 sec
Gel timeReactivity @ 130°F2 sec
Tack-free timeReactivity @ 130°F3 sec
Rise timeReactivity @ 130°F3 sec
Mix ratio by weightA : B117 : 100
Mix ratio by volumeA : B100 : 100
A-side viscosity (A2-000)Brookfield @ 20 rpm, 72°F200 cps
B-side viscosity (B-24-035)Brookfield @ 20 rpm, 72°F700 cps
SEVERE Wastewater — compressive lossASTM D-28420%
SEVERE Wastewater — tensile lossASTM D-284218%

Source: NCFI Terrathane 24-035 Technical Data Sheet (02/08/2022)

Field methodology Installation procedure
  1. Site assessment & probe testing. Dynamic Cone Penetrometer (DCP) testing along the wall to identify soft zones, void depth, and unconfined compressive baseline. Probes are typically driven 3–10 ft below grade.
  2. Layout. Injection ports laid out on 1.5–3 ft centers along the landward face, typically in two offset rows. Port diameter ⅝".
  3. Drilling. Small-diameter drill holes through cap or directly into soil via 6 ft injection rods. No excavation.
  4. Injection. Pre-determined gallon volumes of Terra-Lok 24-120 (single-component) pumped via airless system through the rod, starting at depth and pulled progressively to allow bottom-up permeation. Catalyst selection (Reg Cat vs Fast Cat) chosen for field conditions — water-flow, ambient temp, allowable migration distance.
  5. Verification. Post-injection DCP testing at treated locations. NCFI's St. Petersburg residential case study documented a 699% improvement in California Bearing Ratio (CBR) between treated depths of 3–10 ft (HMI / NCFI case study).
  6. Patch & clean-up. Ports sealed, surface restored. Treated area is load-bearing within hours and weather-resistant immediately.
When polyurethane is NOT the right system Engineering judgment

Polyurethane permeation grouting is a soil-stabilization and water-stop technology. It is not a structural replacement for failed wall elements. Recommend full replacement (and walk away from injection) when any of the following are present:

  • Visible panel lean greater than 3" out of plumb over wall height
  • Multiple panels bowed, rotated, or de-keyed at the tongue-and-groove joint
  • Tiebacks (deadmen) widely rusted through or failed in tension
  • Rebar exposed across multiple panels with active corrosion
  • Cap fully separated from panels or longitudinal cap fracture
  • Foundation toe scour exceeding embedment depth

In these scenarios, soil stabilization may extend the timeline before replacement becomes urgent, but it cannot restore lost structural capacity. A licensed Florida marine PE should be the deciding voice.

Permitting reference FL regulatory context

In most Florida counties, polyurethane permeation grouting behind an existing seawall is classified as soil stabilization — not seawall construction or in-water work — and therefore does not trigger FDEP or USACE permitting. Local building department notification or minor work permits may still apply. Always confirm with the AHJ. This is materially different from any work waterward of mean high water, which falls under FDEP Joint Coastal Permit / USACE Section 10/404 review.

References: FDEP CCCL program · USACE Jacksonville District Regulatory

Client testimonials

Don't take our word for it.

"Gulf Coast Soil and Seawall Docs provided clear guidance for my soil management project, making the process smooth and successful. Thanks to NCFI Geotechnical polyurethanes, my pool deck repair is now sturdy and reliable, ensuring peace of mind for years to come."
Tim JensonPool deck stabilization
"Exceptional service — seamlessly blending beauty with durability in their seawall repair. The innovative foam solution they utilized not only restored the structure but also offered a cost-effective alternative, surpassing other options in affordability."
Stacy KingSeawall repair
"Fantastic! Their professionalism and expertise in repairing our concrete void with foam saved our daughter's birthday plans, all at a surprisingly low cost compared to other options. Highly recommend their services for any concrete repair needs."
Christina WoodConcrete void repair
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Step 3 of 3 · Three ways we can help

Tell us what you need. We'll help you sort it out.

Whether you hire us, hire someone else, or do nothing at all, we want you to have useful information. Pick any combination below — we'll respond within one business day with what you asked for, and nothing more.

  • Send me the punch list & estimate — your custom cost breakdown plus the 12-point contractor punch list delivered by email and text.
  • Discuss my options — a quick 15-minute call (phone or video, your call) to walk through replacement, partial repair, soil stabilization, drainage corrections, or living-shoreline alternatives. Bring photos, a video clip, or just questions — no quote pressure, no commitment to anything beyond the conversation.
  • Schedule a no-obligation consultation — a virtual walkthrough, an on-site visit, or both. We can start over video with you showing us the wall on your phone, then come out in person if it’s worth a closer look. Either way we cover the wall, the yard, the drainage, and the irrigation, and you’ll get a written assessment whether or not you hire anyone.

    What would you like from us? (pick one — we'll respond to what you select)

    No mattress-store countdown clock, no pushy follow-ups, no “today-only” pricing games. Honest direction toward your actual solution — even if that solution isn’t us.

    Before you sign a replacement contract…

    Make sure replacement is actually the right answer.

    Take 90 seconds. You'll get a real Florida price range for your zip code, a 12-point contractor punch list you can use with any bidder, and an honest read on whether less-invasive options — soil stabilization, drainage corrections, partial repair — are worth a second opinion first.

    Full replacement (typical) 4–8 months Demo · permits · barge access · yard restoration
    Soil stabilization (when appropriate) 1–2 days No demo · typically no permits · no torn-up yard
    Free on-site assessment. We'll tell you straight — if your wall needs full replacement, we'll say so and point you to a vetted marine contractor. Use us, use someone else, or do nothing at all.
    FAQ

    What every Florida waterfront owner should know.

    What is polyurethane injection and how does it work?

    Polyurethane injection — sometimes called foam jacking — involves injecting a high-density NCFI Geotechnical foam into the ground or behind the wall. The closed-cell foam expands, hardens, and forms a permanent water-tight barrier that stabilizes soil, lifts concrete, and seals voids. Most jobs are completed in a single day with no excavation.

    Is polyurethane injection durable and long-lasting?

    NCFI polyurethane is chemically inert, hydrophobic, and unaffected by saltwater. The polymer itself is engineered to last a lifetime in the ground — properly installed, it’ll outlive all of us. Our workmanship warranty on the install runs up to 7 years, transferable, tied to the treated soil zone. The chemistry is essentially permanent; the labor we’ll put our name on for 7 years.

    What does a Florida seawall “warranty” actually cover?

    Almost never what homeowners assume. The longest craftsmanship/workmanship warranty most Florida marine contractors offer is 1 year. The “limited lifetime” marketing you see on vinyl sheet pile or composite walls is a manufacturer material warranty — it warrants that the polymer panel itself will not degrade in soil. That is an easy promise: composite plastics aren’t the reason walls fail. Almost nobody in the marine trade warrants against erosion, because erosion happens on the landward side of the wall and is treated as an environmental condition rather than a workmanship defect. Our soil-stabilization warranty is the exception — we warrant the treated soil zone with an up-to-7-year transferable workmanship warranty, backed by a polyurethane engineered to last a lifetime in the ground. The chemistry outlives all of us; we put our name on the install for 7 years. If you take one thing into a contractor meeting, take that distinction.

    Why does Florida seawall pricing vary so much?

    Three reasons: access (can a crane reach the wall?), soil (sand vs. limestone vs. muck), and regional labor. Cape Coral and SWFL run $400–$900/lf; the Panhandle and North FL run $250–$550/lf; Miami-Dade and the Treasure Coast can hit $1,000–$1,500/lf for premium concrete jobs on the Intracoastal.

    Do I really need both FDEP and Army Corps permits?

    For almost every coastal or Intracoastal project, yes — they're not interchangeable. FDEP regulates state-owned submerged lands and water quality. USACE regulates federal navigable waters. One approval does not satisfy the other.

    Can I get an injection repair without permits?

    In most Florida counties, yes — injection is typically classified as soil stabilization, not seawall construction, and requires no FDEP or USACE permit. Always confirm with your local contractor.

    What are the advantages of polyurethane injection over traditional methods?

    Speed: Completed in hours, usable immediately. Minimal disruption: No excavation, just small drill holes. Cost-effective: 70–80% cheaper than replacement. Precision: Foam expands to fill gaps exactly where needed, allowing accurate lifting and leveling.

    How does soil erosion happen behind a Florida seawall?

    It happens in two directions at once. Tidal action and groundwater pressure pull fines through the wall via cap joints, panel seams, and weep holes. At the same time, Mass.gov coastal management warns that overland runoff and wave overtopping erode sediment behind the wall and can create sinkholes that destabilize the structure. Filter fabric and weep holes slow the process — they can't stop it, and they don't address what's happening on the landward side.

    Why is injection better ROI than replacement?

    Injection takes the seawall investment you've already made and extends its useful life by another 25–40 years — typically for 25–30% of what replacement costs. Replacement throws away your existing wall (which usually still has structural life in it) and forces you to start your investment clock over. Injection addresses the actual failure mode — soil erosion — instead of just swapping the panels and letting the same erosion start the cycle over.

    What if my wall is too far gone to save?

    We'll tell you straight — when panels are bowed, tiebacks are widely failed, or the wall is leaning more than 3", soil stabilization isn't the right call. In that case we'll point you toward a vetted Florida marine contractor who specializes in your county's permitting environment. You're free to use anyone you want — the goal is that you walk into the next conversation knowing what to ask.

    Do you offer financing?

    Yes — 0% APR for 12 or 24 months on qualifying projects. Prequalification takes about two minutes and has no impact on your credit score.

    Is this tool really free? What's the catch?

    No catch. We're a Florida solutions-based company that sponsors this calculator because informed homeowners make better decisions — even when those decisions don't involve us. The estimate is free, the punch list is free, and the no-obligation consultation is free. Hire us, hire someone else, or do nothing at all — we'd rather you have the real numbers either way.