Know Your NOMMA: 5 Things to Know About Welded Joint Finishes

In custom metalwork, the smallest details often make the biggest difference. Welded joints may not be the first thing people notice, but they’re one of the most important factors in how a finished railing, staircase, or ornamental feature looks, feels, and performs over time.

That’s where NOMMA joint finish guidelines come in. The National Ornamental & Miscellaneous Metals Association (NOMMA) created a clear set of standards that fabricators, architects, and contractors can use as a common language. These joint finish standards apply to all types of metals and welded joints, ensuring consistency and clarity across the industry. By understanding the NOMMA guidelines, decision makers can better align design intent, budgets, and construction schedules while ensuring the end product meets expectations.

Here are five things every architect, contractor or project owner should know about NOMMA welded joint finishes.

Why joint finishes matter

Welded joints do more than hold metal together. They define the look and durability of the final product. 

Weld quality directly impacts the overall quality of a metal piece, as improperly finished joints can create weak points that lead to rust or corrosion. When it comes to aesthetics, smooth, seamless joints create clean lines that elevate design, while rough or uneven welds can distract from the overall look.

Working with a trusted metal partner like Stewart Iron Works ensures your welds will exceed industry standards, no matter which finish level is selected. Delivering the highest weld quality for our clients is a key component of our 160+ year legacy of master craftsmanship. 

NOMMA finishes are categorized into 4 levels

NOMMA classifies welded joint finishes into four levels. Each provides a baseline of what to expect, giving project teams a shared reference point.

• Finish #1: Welds are finished to a seamless, polished appearance. There’s no visible evidence of a welded joint.
• Finish #2: The joint is completely sanded, but some undercutting and pinholes are acceptable. There’s a uniform, blended look, but it’s not perfect.
• Finish #3: This is a partially dressed weld with the splatter removed. Welds are ground but still visible.
• Finish #4: A uniform undressed weld of good quality with minimal splatter. Suitable where function and utility are the top priority.

These standards apply to all types of metals and joints, including square tube T, square to bar T, pipe T, and raked T joints. They help architects specify requirements clearly and allow contractors to price bids consistently. They also help clients understand why one railing might cost more — or require more time — than another.

How NOMMA finishes impact design

Because welded joints are often small and hidden relative to an overall metal piece, they might seem like an insignificant detail. But in fact, the finish of a welded joint has an enormous visible impact on the overall look of a particular design. The sheer number of welded joints on a structure — whether it’s a railing, a gate or a staircase — means they are likely to be noticed, especially if the selected level is less finished. The better the weld, the more likely it is to blend seamlessly, which contributes to a sleeker, more polished look overall.  

In high-profile places, such as lobbies or concourses, or in ornamental statement pieces, a NOMMA finish #1 is often essential to achieving the desired design intent. And when the scope features multiple elements, such as railings, staircases and partitions, adhering to a consistent NOMMA joint finish standard ensures a cohesive look.

How NOMMA finishes impact budget and schedule

NOMMA finishes have a direct impact on budget because, generally speaking, the better the NOMMA finish, the higher the cost. Welds finished to #1 and #2 standards require more grinding, blending and polishing, which means more time in the shop and a greater strain on parts and equipment. These extra labor and supply costs directly translate to a bigger budget.  

NOMMA finishes also impact schedules, as more seamless finishes may extend fabrication timelines and require additional care during installation.

It is crucial all project teams align on the desired NOMMA finish early in the bidding and estimating phase, as the costs associated with each finish level vary dramatically. Using NOMMA’s guidelines to set the standards helps avoid costly misunderstandings that can derail budgets and schedules. 

How to determine which NOMMA joint finish level is right for your project

Many factors contribute to deciding which NOMMA joint finish is right for a given project, including design intent and budget. One of the first questions we ask our clients to consider is the quality and location of the welded piece. Is it a custom staircase in the center of a corporate lobby or a safety railing behind a loading dock? Will the welded piece impact how visitors experience the space or does it exist purely for function and utility? Will the piece ultimately be painted, helping to disguise any weld imperfections? The answers to questions like these help us make an informed recommendation. 

The budget, too, must be considered. As trusted experts in custom commercial and ornamental metalwork, we help our clients assess and weigh the various factors that contribute to selecting a NOMMA finish. Our goal is to balance aesthetic goals with cost needs to achieve a quality weld that is perfectly suited to a project’s unique specifications.

At Stewart Iron Works, our deep welding expertise and understanding of NOMMA’s joint finish standards are backed by a 160+ year legacy of master craftsmanship. No matter the project, we bring creative solutions, striking design, and trusted expertise to every challenge. Our commitment to doing it right ensures we deliver metalwork that’s made to last.

Looking for a trusted partner to bring your design vision to life? We’d love to hear from you.