How Are Floating Staircases Fabricated? From Steel and Hardwood to a Finished Stair System
One of the defining characteristics of a floating staircase is its simplicity.
A single steel mono-stringer runs beneath thick hardwood treads. Connections are kept clean. Hardware is minimized or concealed. On staircases with integrated lighting, even much of the electrical system disappears inside the finished staircase.
But creating that simple finished appearance requires a surprisingly involved fabrication process.
At Iron Timbers, a custom floating staircase moves through steel selection, CNC laser cutting, welding, grinding, sanding, test assembly, powder coating, hardwood machining, finishing, railing fabrication, optional lighting installation, and final packaging before it is ready to leave our shop.
Here is how an IRON Floating Staircase System goes from approved shop drawings to a finished staircase ready for installation.
Step 1: How Are Floating Staircases Fabricated? It Starts With the Shop Drawings
Before steel is cut, the staircase has already gone through the design and verification process.
The dimensions shown on the shop drawings determine what will ultimately be fabricated, including the staircase geometry, mono-stringer dimensions, riser and tread plate locations, mounting points, railing, and other project-specific details.
Those drawings also determine the steel selected for the mono-stringer.
A typical IRON System may use 5" × 5" × .25" wall steel tube for the mono-stringer, while other staircase designs may require 5" × 7" tubing or heavier wall thicknesses based on the requirements of the staircase.
Rather than selecting material once fabrication begins, the steel entering the shop is based on how that particular staircase system was designed.
Step 2: The Mono-Stringer Is Cut on a CNC Tube Laser
Once the correct material is selected and prepared, the fabrication files are loaded into our industrial CNC tube laser.
The machine does much more than cut the stringer to length.
It also cuts project-specific holes and openings directly into the steel tube. These can include locations for the rivnuts used to mechanically attach our riser/tread plate assemblies as well as openings required for concealed wiring when a staircase includes integrated LED tread lighting.
This allows many of the features required later in fabrication to originate from the same digital files used to produce the staircase.
Want to learn more about the structure at the center of the system? Read “What Is a Mono Stringer Staircase and How Does It Work?”
Step 3: The Other Steel Components Are Cut at the Same Time
The mono-stringer is only one part of the steel staircase.
Before welding begins, we also produce the individual components needed to build the riser/tread plate assemblies.
Our tube laser cuts the steel tubing for the riser assemblies, while our sheet laser cuts the corresponding steel tread plates.
By the time fabrication begins, the major steel components have already been cut according to the project drawings and are ready to be fitted together in the shop.
Step 4: Each Riser and Tread Plate Assembly Is Fabricated
The laser-cut riser tubing and steel tread plates are brought to our fabrication tables, where each assembly is individually fitted and welded.
After welding, the assemblies are ground and sanded to prepare the steel for its finished appearance.
Each assembly is then inspected and set aside as the rest of the staircase moves through fabrication.
These assemblies eventually become the steel structure directly beneath each hardwood tread.
Step 5: The Mono-Stringer Is Prepared and Fabricated
Before the staircase can be assembled, additional work happens to the mono-stringer itself.
The attachment holes created by the tube laser are prepared to accept recessed rivnuts. Those rivnuts ultimately provide the mechanical connection between the mono-stringer and the individual riser/tread plate assemblies.
The individual stringer sections are then prepared, fitted, and welded together. Top and bottom mounting plates are also welded to the stringer as required by the staircase design.
Once welding is complete, the joints are carefully ground and sanded.
This is one of the places where a significant amount of fabrication work intentionally disappears from the finished product.
Our goal is for the welded transitions between stringer sections to appear seamless once the final powder-coated finish is applied. When you look at the completed staircase, you shouldn't immediately see where one fabricated section ends and another begins.
Finally, the rivnuts are installed into the prepared attachment locations so the riser/tread assemblies can be mechanically fastened to the stringer.
Step 6: We Assemble the Steel Staircase in Our Shop
Before anything is sent for powder coating, the staircase is physically assembled in our shop.
Using our fabrication tables and fab blocks, the stringer sections are positioned and the individual riser/tread plate assemblies are mechanically attached.
This gives our fabrication team the opportunity to see the staircase come together as a complete steel system and verify that the fabricated components assemble as intended according to the shop drawings that were previously verified against field conditions.
That step matters because once the components have been powder coated, the complete staircase will not normally be assembled again at Iron Timbers.
The next full assembly happens at the jobsite.
Step 7: The Steel Is Prepared for Powder Coating
After the shop assembly has been verified, the staircase is disassembled and the individual steel components receive a final inspection.
We look for blemishes, sharp edges, or other areas requiring attention before the components leave our shop.
The stringers, riser/tread plate assemblies, and other applicable steel components are then sent to our outside powder-coating partner.
Matte black is one of the most common finishes selected for our floating staircase systems, although finish selections can vary by project.
When the powder-coated components return, the primary steel fabrication work is complete.
If the staircase does not include integrated lighting, the steel can begin moving toward packaging and shipment. If lighting is included, there is another important step.
Step 8: Concealed Lighting Is Added When Specified
Integrated tread lighting is a good example of how much work can exist behind a feature that appears extremely simple once the staircase is installed.
When a lighting package is included, openings incorporated into the steel during laser cutting allow low-voltage wiring to be routed through the staircase structure.
After powder coating, the stringers are wired so that much of the electrical infrastructure can remain concealed within the finished staircase.
The goal is ultimately the opposite of showing off the complexity: when the staircase is finished, you see illuminated hardwood treads, not the work required to get power to them.
That additional machining, wiring, and coordination is one reason integrated lighting can represent a significant upgrade to a custom floating staircase.
See how lighting can be integrated into the staircase in “Floating Staircase Lighting Ideas: How to Illuminate a Modern Staircase.”
Step 9: The Hardwood Treads Go Through Their Own Production Process
While the steel staircase moves through fabrication, the hardwood treads follow a separate production path.
Iron Timbers sources the hardwood treads from our tread supplier and then performs the project-specific machining and finishing in our woodshop.
At a minimum, each tread is CNC-machined to create the recess required for the steel tread plate. The treads are then inspected and sanded in preparation for finishing.
We finish our hardwood treads with Rubio Monocoat Oil Plus 2C, a hardwax-oil finish that bonds with the upper wood fibers rather than creating a traditional film over the surface.
When integrated lighting is included, additional CNC machining creates the channel for the lighting system. After the wood finish has dried sufficiently, the lighting components can be installed into the treads before they are protected and packaged for shipment.
Learn more about tread construction and proportions in “How Thick Should Floating Staircase Treads Be?”
Step 10: The Steel Railing Is Fabricated
The railing is another custom-fabricated component of the staircase package.
Using the project shop drawings, the individual railing pieces are cut to the required dimensions and laid out on our fabrication tables.
The components are then fitted and welded together into the railing sections required for that particular staircase before being prepared for powder coating.
Because the railing, steel staircase, and hardwood components are all being produced around the same project, they ultimately come together as parts of one coordinated staircase package rather than independent products sourced for the same opening.
Step 11: Everything Is Prepared for Shipment
Once the powder-coated steel, finished hardwood treads, railing, hardware, and any lighting components are complete, the staircase can be prepared for freight.
Packaging varies depending on the size and complexity of the project.
Stringers will typically ship on their own skid or inside a crate. On larger projects with multiple components, several pieces may be organized together on heavy-duty skids.
Finished components are wrapped with protective material to help prevent damage to the powder-coated and finished surfaces and are secured to the skids with banding as needed.
The objective is to turn everything that has moved through different areas of our shop into one coordinated staircase package ready to travel to the project.
See how we coordinate complete staircase systems for projects across the country in “How Iron Timbers Builds and Ships Custom Floating Staircases Nationwide.”
Why Build the Staircase as One Complete System?
A homeowner or contractor can source the different pieces of a floating staircase independently.
The steel structure can come from one fabricator. Hardwood treads can come from another supplier.
Railing can be fabricated locally. Finishing can be handled somewhere else. Lighting can become another separate scope.
But now someone has to make sure all of those pieces actually work together.
That's the problem we try to remove.
Iron Timbers coordinates the mono-stringer, riser/tread plate assemblies, hardwood treads, railing, finishes, hardware, and optional lighting as one complete staircase package.
For the homeowner or contractor, that means less time trying to source and coordinate multiple specialty suppliers and fewer interfaces between companies that may each be working from their own interpretation of the staircase.
Simple by Design Doesn't Mean Simple to Build
That's ultimately what makes the fabrication of a floating staircase interesting.
A well-executed mono-stringer staircase can look incredibly simple when it's finished.
That's intentional.
You don't see the laser-cut rivnut locations hidden beneath the tread assemblies. You don't see the individual sections of steel that were fitted, welded, ground, and sanded until the joints disappeared. You don't see the CNC-machined recesses underneath the hardwood treads. And on an illuminated staircase, much of the wiring that took additional planning and labor is deliberately concealed.
What remains is the part you're supposed to see: a clean steel structure, substantial hardwood treads, and a staircase that appears simple enough to float through the space.
Behind that simplicity is the fabrication process that makes an IRON Floating Staircase System possible.
Planning a Custom Floating Staircase?
If you're planning a new build or renovation, you don't have to wait until you're ready for fabrication to start the conversation.
Send Iron Timbers your architectural plans or preliminary staircase dimensions. We can review the proposed staircase, discuss material and design options, and develop an initial quote for your project.
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