Vortex Logo

Fiberglass vs. Steel Doors – Which is Better?

July 5, 2023 | Commercial Doors

Businesses need doors they can rely on. Wood looks great, but it’s costly, high maintenance, and breaks down in extreme weather. Which is why most businesses choose fiberglass or steel instead. Each has its own strengths and weaknesses, so, in order to help you decide which is a better fit for your company, let’s take a look at the relative merits of fiberglass vs. steel doors.


Fiberglass and steel doors aren’t made from solid material. Instead, they consist of a polystyrene or polyurethane core, encased in fiberglass or steel. Most steel doors are made from 20-26 gauge steel (0.04-0.02 inches; lower gauges are thicker than higher ones). But while steel doors have solid steel casing, fiberglass doors are made from a composite of fiberglass reinforced plastic with hardwood framework.


Fiberglass doors have a wide range of finishes. Not only can you paint them any color you want, you can even treat them to give them the appearance of a wooden door. This isn’t the case with steel doors. You can paint them, but there are no available finishes. However, both doors can support lites (glass windows) and decorative flourishes, such as molding or transoms.


Both fiberglass and steel doors are low maintenance, though fiberglass has a slight edge. Like steel, fiberglass resists dents and dings and doesn’t swell, expand, or rot in moist or humid environments. Repeated contractions can cause steel doors to crack, though even under the worst conditions it would take at least a decade. Steel is highly resilient. It resists dents and dings better than fiberglass and stands up well in heavy weather as long as it’s regularly repainted or varnished. In fact, with proper upkeep, a steel door will last as long as a fiberglass one, with each requiring only minimal effort to maintain.

Weather Resistance

Though steel and fiberglass both stand up well against the elements, fiberglass has a slight, long-term advantage because it doesn’t rust or transfer heat. Fiberglass doors have an R-value of six or seven, making them one of the best insulators on the market. Steel doors, on the other hand, have an R-value of five or six ‒ still a strong insulator, just not as strong as fiberglass.
Steel rusts only if it’s not well maintained. Any scratches or dents that damage its galvanized finish expose the bare metal underneath, which can lead to corrosion. Fortunately, most damage can be repaired at low cost. A layer of putty and a fresh coat of paint will seal most scratches and restore the door.


Nothing protects your building better than steel. It bends, but doesn’t break. Rocks, crowbars, and sledgehammers are almost totally ineffective against it. Only the strongest impacts can punch through, which makes it immune to common burglar tools. Fiberglass is tough, but doesn’t provide the same level of protection.

Deciding Between Fiberglass vs. Steel Doors

When it comes to fiberglass vs. steel doors, Vortex Doors is committed to providing you with the best advice and support. We not only install and maintain your doors. We help evaluate your building, so you can be assured the doors you choose are the ones best suited to your needs. No matter how big or small the project, we’ll find a solution. Contact us today!

Want to SHARE this?

Fully Certified & Accredited Commercial Door Experts

IDEA logo
Lead Safe EPA logo
ISN RAVS Plus Participant Logo
NFPA logo
AAADM logo
IDEA logoLead Safe EPA logo
ISN RAVS Plus Participant Logo
NFPA logoAAADM logo

What Our Customers Are Saying

dhill41410 ★★★★★ Great service from the Salt Lake branch of Vortex on our overhead door repair. After 20 years of use, our door was in need of repair as it would no longer open. Service technician Brett S. Arrived at our business, evaluated the problem, ordered parts and ,once parts were acquired, returned to complete the work. Brett gave detailed explanation of the repairs needed and was professional at every interaction that we had throughout the entire process. We are satisfied with this repair and the repairs Vortex has performed for us in the past. Would recommend to those in need and will use Vortex again in the future as the needs arise.Brandon M. ★★★★★ Saul and jr did a great service for our front door restaurant soul food shackJonathan P. ★★★★☆ Javier and Tony B came out, same day, got my door running. Great job!hanniel C. ★★★★★ Tom and Colton came exactly on time, fixed the broken door in no time at all and helped get me pricing on remotes. Super happy with their work, definitely definitely recommendQ B. ★★★★★ Excellent ServiceGabby G. ★★★★★ Very happy when your staff members come out and fix our issues and also take the time to give us a thorough assessment.Kevyn H. ★★★★★ Victor Estrada and Juan Lopez outstanding and professional!Joshua R. ★★★★★ VORTEX DOORS ARE THE BEST. We just had Cotton & Wade service our warehouse door and they went beyond and above to get this done for me.I highly recommend this company. They are amazing. I’ll definitely be back.Tuz N. ★★★★★ Kevin and Dustin were great. Quick and easy service. Came out same day and helped out my stores. Can’t recommend them enoughjs_loader

Perfect service, incredibly fast.

Please call us at (800) 698-6783

Contact Us