Service 04

Structural
Fiberglass Repair

Transom softness, delamination, through-hull failures, major impact damage. When the job goes beyond cosmetic work, we have the depth to handle it — backed by 35+ years of structural fiberglass expertise.

Structural Assessment Indicators
Transom SoftnessFlex or give when pressing the transom by hand. Water has penetrated the core and the laminate structure is compromised.
DelaminationBubbling, separation, or hollow sound when tapping. The bond between laminate layers has failed.
Significant Impact VoidImpact damage where tap testing reveals voiding beyond the visible surface. The laminate has compressed internally.
Through-Hull Area DamageDamage in proximity to through-hulls, fittings, or hardware. Requires careful assessment before any repair work.
What We Do

Structure first.
Finish second. Always.

Structural fiberglass repair is the work that happens before anyone sees the result. Laminate reconstruction, transom rebuilding, core replacement — these are the repairs that determine whether a boat is safe and sound, not just whether it looks right.

Michigan's freeze-thaw cycle is harder on structural voids than almost any other climate. Water that gets into a delamination or transom void expands on freezing. What was a manageable repair in October becomes significantly more involved by spring.

We assess the full structural picture before quoting. Some jobs that look structural are cosmetic. Some that look cosmetic have structural implications. We tell you which you're dealing with before any work begins.

Scope of Work
Transom RebuildingFull transom core replacement and laminate reconstruction. The most common structural repair on aging fiberglass boats.
Delamination RepairRebonding or replacement of separated laminate layers. Scope varies widely — we map the extent before quoting.
Major Impact ReconstructionSignificant collision or grounding damage requiring laminate rebuilding before any cosmetic work.
Extended On-Site ProjectsFor major structural work, full on-site setup for the duration of the project is available. The job doesn't have to move to us.
The Process

Structural repair done in the right order.

01

Structural Assessment

Tap testing, flex testing, and visual inspection to map the extent of structural compromise. We don't quote structural work from photos alone — the assessment is part of the drop-off intake or the mobile on-site evaluation.

02

Access & Removal

Damaged laminate, saturated core, and compromised material is removed to sound substrate. The scope of this step often determines the final cost more than anything else — we document what we find and confirm before proceeding.

03

Laminate Reconstruction

Fiberglass cloth wet layup built back up to the original thickness and profile. Layer count, cloth weight, and resin system selected for the specific structural requirement. Cure time is not rushed — structural laminate needs to reach full cure before the next step.

04

Fairing & Surface Preparation

Rebuilt structure faired to the original profile. For transom work, motor mount geometry is verified. For hull repairs, the repaired section is prepared to match the surrounding hull contour before any finish work begins.

05

Gel Coat & Finish

Once structure is confirmed sound, finish work proceeds — same process as our gel coat restoration and cosmetic repair work. Color matching on the repaired area is always best effort on aged hulls, as documented in our service agreement.

The Cooper Bench

When the job calls for it,
the depth is there.

Structural fiberglass work is where the Cooper family trade runs deepest. For major structural projects, John works alongside David Cooper — known throughout the regional marine industry as the Yacht Doctor.

35+ years in the trade. Hurricane Hugo. Hurricane Andrew. Boat plants and manufacturers from San Diego to Virginia. When something unusual comes up on a structural job, we know who to call and what questions to ask.

Two brands. One standard.

David Cooper
The Yacht Doctor

35+ years of structural fiberglass expertise. Available for complex structural evaluation, extended on-site projects, and any job that requires depth beyond cosmetic repair. Known throughout Southeastern Michigan's marine industry.

Structural laminate Transom rebuilding Delamination Extended on-site Expert evaluation Industry relationships
Project Gallery

Work in progress.

Photos coming as jobs are completed. Structural work photography should show the process — raw laminate, layup in progress, and the finished result.

Photo 01

Transom damage before repair — soft, saturated core revealed after access cut

Photo 02

Fiberglass cloth layup in progress — wet-out mat visible, layers building up

Photo 03

Completed structural repair — faired and finished, motor mount geometry verified

90-Day Workmanship Warranty

All workmanship is warranted for 90 days from service completion. Structural repairs are covered for defects in workmanship only — not subsequent impact, improper use, or conditions outside our control. We document the scope of work and what was found at each stage.

Common Questions

What we hear most about structural work.

Press on the transom near the motor mount by hand. Solid transoms don't flex. Soft transoms have give — sometimes subtle, sometimes significant. If you hear a hollow sound when tapping, or if there's visible delamination at the transom cap or corners, it's worth a proper assessment. Text us a description and we'll tell you whether it warrants a look.
Either. Most structural work can be performed at your marina or storage facility — our mobile setup includes everything needed for full laminate work. For extended projects, we can establish a full on-site setup for the duration. Drop-off at our Redford facility is also an option and gives us better access for certain transom configurations.
Significantly longer than cosmetic work — laminate needs cure time at each stage, and cure rate depends on temperature and humidity. A transom rebuild is typically a multi-day job at minimum. We'll give you a realistic timeline at assessment, not an optimistic one. Michigan weather is a variable we account for honestly.
We stop and document before proceeding. Structural repairs sometimes reveal more than the initial assessment showed — saturated core that extends further than expected, or delamination beneath the visible damage. We photograph what we find, communicate with you, and get approval before expanding scope. Nothing proceeds without your sign-off.
Next Service
Hull Buff Out & Polish
Learn More →
Get Started

Structural concerns
don't wait.

Call or text (248) 916-9166. Describe what you're seeing — soft transom, hollow sound, visible delamination — and we'll tell you how urgent it is and what a proper assessment involves.

Drop-off · Redford Township · $800 minimum  ·  Mobile · Southeastern Michigan · $1,200 minimum