Fire-Rated Doors 101: Learn More about Commercial FRP Fire Doors

If you love one or all of our Special-Lite fiberglass doors, did you know we have a harmonizing fire-rated model available too?

Special-Lite is the manufacturing leader for fiberglass doors. In 35+ years, we migrated from the first and best fiberglass school door into many markets and industries – all having unique door needs. One of those needs is a fire-rated fiberglass door to use in rated entrance locations to match our door products. We solved this need through engineering and by challenging our expert craftspeople to manufacture fire-rated fiberglass doors and frames. They are perfect for new construction or retrofit projects.

We offer two fire-rated fiberglass door types: FRP/Stainless Steel & Fiberglass

What? Yes, both construction types use FRP face sheets, but the construction method and design are different. It is important that you understand the unique construction methods so you can select the type best suited to your location.

FRP/Stainless Steel Fire-Rated Door

Special-Lite builds FRP/Stainless Steel fire-rated doors using a fire-resistant mineral core in 30, 45, 60, and 90-minute rated versions. We chemically bond FRP face sheets to this mineral core. We screw-apply the stainless edges, then weld and buff the corners. Stainless steel vision lite kits are also an available option!

Our fiberglass fire doors are hand measured throughout the entire process to ensure we meet specifications. Custom-built punches used by skilled craftspeople deliver precision edge preps on the stainless steel edge pieces. These punches prep for hardware such as mortise locks, strikes, and flush bolts.


Below you can see a graphic representation of the FRP/Stainless Steel fire-rated door’s construction. Fire-rated cores are ordered to fit specifications and are reinforced on the top, bottom, and hardware areas. The stainless steel door edge is durable and protects the door edge from damage involving gym bags, suitcases, hospital beds, and equipment.


Fiberglass Fire-Rated Door 

Our other fiberglass fire-rated door construction does not utilize stainless steel door edges. We construct these doors with a fire-rated mineral core featuring edge blocking for superior screw hold performance. We again chemically bond FRP face sheets to the mineral cores. You can order these fiberglass fire-rated doors in many size variations, with fire ratings from 20 to 90 minutes.

  all-fiberglass-fire-01 cross-section-01  

In the drawing above notice the pultruded fiberglass fire-rated door frame! When you combine this pultruded fiberglass fire-rated framing with our fiberglass fire-rated door, you will enjoy a beautiful, complete and cohesive entry system!

Both the Fiberglass Fire-Rated Door and the FRP/Stainless Steel Fire-Rated Door construction uses our .120” thick fiberglass face sheets giving our customers many options:

  1. AMP Wood Grain (Fiberglass) Face Sheet We are very excited to offer you a faux wood grain fire-rated door, the Fire-Rated AMP-Clad SL-22! A wood grain look presents many design opportunities for a warm and home-like feel without sacrificing the durability of FRP.  This door is perfect for hospitals, long-term care facilities, retirement residences, hotels, educational housing, places of worship, and traditional education buildings. If your design team has chosen to use our SL-19 flush or SL-18 colonial doors, the SL-22 is the fire door for you! Below is a photo featuring a hotel with this door!
  1. Pebble Grain SpecLite 3® FRP (Fiberglass Reinforced Polyester) Face Sheet Our most popular FRP face sheet is used on both the SL-21 and the FR-20P/45P/60P/90P fire doors. The pebble grain FRP face sheet, our proprietary SpecLite 3®, unlike competitors’ pebble grain FRP sheets has a mylar coating. This coating provides scratch and graffiti resistance, as well as making doors incredibly easy to clean. This face sheet is available in 12 standard thru-color options. This option is the perfect choice for any location experiencing hard use or abuse. Also, this is the same face sheet used on the SL-17 and the AF-217 non-fire-rated doors so our customers may coordinate as required.
  2. Sandstone Textured FRP (Fiberglass Reinforced Polyester) Face Sheet You’ll find the sandstone texture FRP face sheet on both the SL-23 and the FR-20S/45S/60S/90S fire doors. The sandstone textured FRP face sheet provides a smoother look than the pebble grain for applications such as schools, childcare centers, hospitals, and industrial buildings. This face sheet is available in all 9 standard thru-color options. Also, this is the same face sheet used on the SL-20 and AF-220 door non-fire-rated doors so our customers may coordinate as desired.
  3. Smooth FRP Face Sheet We use our smooth FRP face sheet on only one of our fire-rated doors – the FR-20/45/60/90. This option provides a beautiful, sleek, modern, and easily cleanable surface. Hermetically sealed with no cracks or crevices, these fire doors are impervious to moisture, chemicals, and bacteria. Standard color selections include 10 standard colors, and the option to use custom colors. All finishes are industrial two-part aliphatic polyurethane, which meets USDA qualifications for incidental food contact. These fire-rated doors are perfect for food prep areas, schools, fitness centers, and pharmaceutical applications. We also think you could get creative with the modern look and color selection and use this durable door for a variety of industries or buildings. Gloss black in an upscale hotel, anyone? This smooth fiberglass fire-rated door works seamlessly with the AF-100 and AF-200!

Our fire-rated doors are compatible with a wide variety of hardware. Particularly relevant is the ability to have surface vertical rods less bottom rods on our FRP/Stainless Steel models, which is preferable by hospitals. Hardware compatibility for both fire-rated constructions is listed below:


Complete Fire-Rated Entrance (Door & Frame)

Complete your fiberglass fire-rated entrance with a pultruded fiberglass frame that cannot rust or corrode! If you cannot replace the existing fire-rated frames, ask about Special-Lite’s insert frame and capping system for your retrofit project. Confused? Don’t be. Just call and let us help you select the perfect door and frame for your fire-rated location.

Open the Door to Saving Energy

How to find Thermal Performing Doors to meet your Climate Zone

You have many opportunities to save energy. Take advantage of these opportunities and use your power and desire to conserve when choosing building products. You may find this especially relevant if you are in commercial construction, due to your State likely adopting their own Building Energy Codes Program. All but 8 States within the U.S. (according to BCAP) have adopted programs for public building exterior energy performance (as you can see below). The most common building energy code adopted by the States is ASHRAE 90.1.
bcap energy codes map
Via: Building Codes Assistance Project
ASHRAE 90.1 breaks the United States into climate zones, each with its own energy performance standard. Look at the Climate Zone Map below and find your location’s climate zone.
ashrae commercial building energy zone map
ASHRAE 90.1 specifies commercial, exterior doors and frames comply with the following independent, standard testing: Air Leakage:        AAMA/WDMA/CSA 101/I.S.2/A440, NFRC 400 or ASTM E283 U-Factor:             NFRC 100 SHGC & VT          NFRC 200 Important Test Notes:
  1. NFRC specifies that non-residential door assemblies, less than ½ glass, meet Opaque Doors Swinging performance requirement; and non-residential door assemblies, more than ½ glass, meet Fenestration Metal Framing & Entrance Door performance requirements.
  2. Most noteworthy, NFRC sets a minimum test assembly size (single door in a frame) of 37 ¾” x 82 3/8”. Why? The larger the test assembly, the better the performance will appear to be. As a result, a standard test size ‘levels the playing field’.

If you are ready to Open the Door to Saving Energy, first discover your Climate Zone and purchase exterior doors and frames that meet the ASHRAE 90.1 Energy Standard. Let’s make it even easier for you to begin. The toughest to meet performance requirement climate zones are Zones 6, 7 & 8. All 3 of these Zones have identical requirements: Ashrae door zones test results Special-Lite’s Mission Statement for 20 years has included the statement, “Don’t hurt the environment”. As a result, our most popular exterior door and frame meets and exceeds the ASHRAE 90.1 Energy Standard for Zone 6, 7 & 8. Furthermore, we continue to independently test all of our entrance products to bring you more solutions to ROCK YOUR WORLD. So, if you don’t see your favorite Special-Lite product on the graph below, call us! We may have the testing completed already! special-lite ashrae thermal performance testing u-value

Some Background Information

What is ASHRAE? From the website: “ASHRAE, founded in 1894, is a global society advancing human well-being through sustainable technology for the built environment. The Society and its members focus on building systems, energy efficiency, indoor air quality, refrigeration and sustainability within the industry. Through research, standards writing, publishing and continuing education, [we] shape tomorrow’s built environment today. ASHRAE formed as the “American Society of Heating, Refrigerating, and Air-Conditioning Engineers” by the merger in 1959 of American Society of Heating and Air-Conditioning Engineers (ASHAE) founded in 1894 and The American Society of Refrigerating Engineers (ASRE) founded in 1904.” ASHRAE 90.1 Finally, ASHRAE 90.1 is also an industry standard referenced by the USGBC in the LEED building certification program. It is frequently used as a baseline for comparison during energy retrofit projects or any project that employs building energy simulation.

How to Measure an Opening for a New Entrance

Measuring an opening for new framing and doors is simple in theory, but it is all too easy to make small and avoidable mistakes that can lead to big headaches later.

There are two basic approaches to sizing new entrances: measuring the opening and letting Special-Lite determine net frame (and door) sizes, or providing Special-Lite with net frame sizes. If providing net frame sizes to Special-Lite, it is important to provide tip-to-tip frame dimensions, because our doors and frames are not manufactured to be field adjustable. We will not make the frame undersize to allow for shim space, so the accuracy of the sizes you provide is critical. For retrofit installations, it is important to adhere to the following recommended best practices when measuring openings.

To Measure for New Doors and Frames:

Inspect the entire opening, both interior and exterior, noting differences in:

  • Floor heights and conditions (rough or finished)
  • Opening width dimensions and wall conditions
  • Header or ceiling heights and conditions
Measuring Width Measuring Height

It may be necessary to remove a piece of trim to determine the exact nature of the rough opening. This will ensure you take correct measurements from masonry to masonry. Getting accurate measurements of the rough opening at this stage should avoid any nasty surprises when removing the old entrance.

Measuring the Opening (Figure A):

  • Measure interior-side opening width (horizontal) at top, center and bottom.
  • Measure exterior-side opening width(horizontal) at top, center and bottom.
  • Record the smallest of these six rough opening width dimensions.
Figure A Measuring Opening

(Figure B)

  • Measure opening height (vertical) from underside of header to floor at left and right jamb and center locations. Be sure to allow for final floor height if floor is still in rough condition. Account for any header height differences, interior to exterior.
  • Record the smallest of these six dimensions as the rough opening height.

Figure B Measuring Opening

Completing Special-Lite Estimate/Order Forms:

  • Use a consistent format for recording dimensional units (decimals vs. fractions).
  • Record rough opening sizes, remembering it is better to err on the small side.
  • Be sure to note whether dimensions provided are rough opening or net frame size.
  • Use separate forms for each opening.

The Special-Lite Estimate/Order Forms make a great checklist to ensure that all required information has been provided. They also eliminate guesswork and help to reduce order lead times.

One Last Tip:

Finally, always carefully inspect and measure new entrance products to ensure everything is sized correctly before demolition of the old entrance. Following these guidelines should greatly reduce the likelihood of problems and frustrations at installation.


Infographic: Fiberglass Reinforced Polyester FRP Door

Learn More About How Fiberglass and Aluminum Innovations Can Benefit Your Facility

Your building’s first impression is its entrance doors and all who enter touch those doors. Is your visitor’s first impression one of cleanliness, safety, and welcome? Traditional options for schools, universities, and government entrances show the abuse they receive. These doors waste maintenance hours. They need frequent repairs, repainting, and replacement, and often have hardware malfunctions. Are your traditional hollow metal or wood doors eco-friendly? Do they lack the thermal performance to save on heating and cooling costs? These reasons may have you contemplating the investment of a more modern solution for a long, maintenance-free life: FRP. You may also hear them called Fiberglass Reinforced Polyester doors or FRP Aluminum Hybrid doors. These doors deliver the ideal combination of benefits which we’ve detailed in this FRP Door Infographic (select image for PDF): frp-school-door-infographic
  The SL-17 fiberglass door has swept the education market, becoming synonymous with “school door.” Special-Lite has also met the demand for custom options to suit aesthetics desired by many different industries! Our doors prove to be an excellent value for building owners. As a result, many door companies try to imitate, but never replicate, the design and materials. Contact us today about the unique construction and proprietary materials that make Special-Lite the most specified FRP door!