Portfolio  /  Fabrication

Beach House
Stair Replacement

A full stair system replacement for a coastal home — from storm-damaged wooden stairs to a custom-engineered aluminum-frame structure with Douglas fir treads, designed for decades of saltwater exposure.

Location Coastal Beach House
Frame Aluminum Extrusion
Treads Douglas Fir
Stringer Length 152.41″
Rise / Step 7.5″
Steps 12
Sealant 3M Marine 4200FC
01 — The Problem

Deteriorated Beyond Repair

Years of saltwater exposure, sand erosion, and storm damage left the original wood stair structure beyond repair. Replacement was the only path forward.

Collapsed original beach house stairs, front view

The original stairs had been compromised after years of service — structural failure of the stringers and hardware from years of sand abuse and wood decay.

Side view of deteriorated original stairs

Side view showing the extent of degradation in the wooden stringers and tread supports.

Rotted wood and corroded hardware beneath the deck

Hardware corrosion and wood rot beneath the stair deck.

Severely rusted hinge assembly

Hinge hardware showing years of saltwater and sand exposure.

Deteriorated wood joint at load-bearing connection

Structural wood members split and failed at key load-bearing joints.

02 — Engineering & Design

Designed for Longevity

The replacement was engineered in aluminum — corrosion-resistant and built for the coast. CAD was used to create the spec and visualize the look: 12 steps at 7.5″ rise, 10.25″ tread depth, 152.41″ stringer length. Douglas fir treads seat in aluminum channels.

3D isometric CAD render of aluminum stair system with Douglas fir treads

3D isometric render — aluminum frame with Douglas fir tread layout. The modular bracket system allows each tread to be individually serviced.

2D CAD drawing with dimensions

Dimensioned 2D drawing. 7.5″ rise per step · 10.25″ tread depth · 152.41″ stringer length · 4″ stringer thickness.

03 — Fabrication

Built in the Shop

Stringers were cut and welded to spec. Treads were pre-cut and drilled to a precise fit, bonded with 3M 4200FC and P591 primer. Nylon sleeve washers at every stainless/aluminum interface prevent galvanic corrosion.

Completed aluminum stair frame laid out in fabrication shop

The completed aluminum stringer assembly in the fabrication shop — all 12 tread brackets positioned and ready for treads.

Workshop overview with completed aluminum frame and fabricator

P591 primer by 3M was applied at every tread-to-aluminum interface to crosslink the polyurethane adhesive to the aluminum, ensuring a long-lasting structural bond.

Douglas fir treads being fitted onto aluminum frame

Douglas fir treads being fitted into the aluminum channels in the shop.

Pre-cut Douglas fir tread boards stacked and ready

Mock-up adhesive test — treads fitted and loaded to validate bond strength before final assembly.

3M Marine 4200FC sealant tube with aluminum bracket detail

Shop overview with the fully assembled aluminum frame prior to tread installation.

04 — Installation & Result

Built to Last

Assembled in the shop and transported on a Whaler trailer, the staircase was lifted into position in one day. The original custom 316 stainless hinge hardware was reused, reconnected to the new aluminum frame to preserve the seasonal lift capability.

Fully assembled staircase loaded on Whaler trailer for transport

Fully assembled and loaded on a Whaler trailer, ready for transport.

New aluminum top plate bolted to existing deck framing from below

New aluminum top plate bolted to the existing deck framing — viewed from below.

Original 316 stainless hinge hardware reconnected to new aluminum frame

Stainless hardware with nylon washers showcased here.

Finished beach house stairs from beach level, full view

The completed installation — aluminum frame and Douglas fir treads, deck to beach.

Side view of installed stairs from beach

Side view from the beach.

Looking down the stairs toward the beach from the top deck

View from the top deck.

Wide view of installed stairs from the beach

Full view in context with the house.