Superior RD-36 Fireplace Doors — Custom Exact-Fit Replacement
Replacement Doors for the Superior RD-36 Fireplace
The Superior RD-36 is a 36-inch radiant wood-burning fireplace that Superior built into countless homes through the 1980s and 1990s. If you own one, the doors are usually the first thing to go: hinges sag, glass cracks, mesh tears, and the black finish burns off long before the firebox itself wears out. The firebox is fine — it just needs a proper set of doors.
First, confirm what you have. Look for the metal rating plate inside the firebox: it is typically riveted to the side wall of the firebox, on the smoke shield, or tucked behind the lower louvers or screen pull. You may need a flashlight and a damp rag to read it. If the plate says RD-36 (sometimes written RD36), you are in the right place. The RD-36 belongs to the same Superior door family as the BC36, BR36, HC36, and BBV36, so if your plate shows one of those instead, the same process below applies.
Why You Can't Just Buy the Original Doors Anymore
Superior has changed hands more than once since your fireplace was installed, and the original RD-36 door assemblies have been discontinued for years. What is left on the market is a patchwork of "fits RD36" listings that assume your firebox still has its factory tracks and clips intact — a big assumption on a fireplace that has been burning for three or four decades.
Universal masonry-style doors are not the answer either, for three reasons:
- Prefab needs an exact fit. A factory-built firebox has a thin metal face, not a flat brick surround. A generic overlap door has nothing solid to anchor to and leaves gaps that look bad and leak air.
- Inside-fit geometry. Doors for a prefab like the RD-36 sit inside the opening, against the firebox face. That opening is rarely perfectly square after decades of heat cycling, and the actual dimensions vary from one installation to the next — which is exactly why we do not print a one-size-fits-all measurement here.
- Safety listing. A prefab fireplace is a tested, listed appliance. Doors need to respect its airflow design. Bolting on an airtight masonry door can starve the firebox and overheat components it was never designed to protect.
Our Approach: Doors Built to the Eighth of an Inch
ExceptionalFire builds replacement doors for the Superior RD-36 to order, sized to your actual opening — not to a decades-old catalog spec your fireplace may no longer match. Every frame is made to the measurements you give us, accurate to 1/8", with an inside-fit design that installs against the firebox face the way the original did. No dependence on surviving factory tracks or clips.
Not sure your fireplace is really an RD-36, or can't find the rating plate? Take a photo of the fireplace and let our AI Fireplace Expert identify it — it takes about 15 seconds and tells you which door style fits your model. From there, our online configurator on the prefab door collection gives you a live price as you pick your frame style, finish, mesh, and glass options. What you see is what you pay — no "call for quote" runaround.
How to Measure Your RD-36 Opening
Measuring takes five minutes with a tape measure. In short: measure the width of the opening at the top, middle, and bottom, and the height at the left, center, and right — openings settle and are rarely square, so we ask for all six numbers. Measure the actual metal opening of the firebox, not the brick or facing around it. Our step-by-step measuring guide walks you through it with photos, shows where the tape should land on a Superior firebox, and explains what to do if your louvers or trim overlap the opening. Send us those numbers and we build to them.
What Not to Do with an RD-36 and New Doors
| Don't do this | Why |
|---|---|
| Burn with tempered-glass doors closed | Standard practice for prefab fireplaces: doors stay fully open while the fire is burning. Close them only after the fire has died down, to stop room air from escaping up the flue overnight. |
| Order doors from the old catalog spec without measuring | Actual opening size varies by installation and by decades of heat movement. Measure your firebox, every time. |
| Force a masonry/overlap door onto the prefab face | No solid anchoring surface, poor seal, and it can interfere with the firebox's designed airflow. |
| Seal the opening airtight | The RD-36 was listed and tested with specific clearances and airflow. Doors should fit precisely, not suffocate the firebox. |
| Drill into the firebox liner or refractory panels | Cracked refractory is a safety issue and an expensive repair. Proper doors mount to the face, not the liner. |
Frequently Asked Questions
Can I still get replacement fireplace doors for a Superior RD-36?
Yes — not from Superior, but custom-built. We manufacture new inside-fit doors sized to your exact RD-36 opening, so you are not gambling on leftover stock or worn-out factory tracks.
Where is the model number on a Superior RD-36 fireplace?
On a metal rating plate inside the firebox — usually on the side wall or behind the lower louvers. If it is unreadable, a quick photo through our AI Fireplace Expert identifies the model for you.
Can I burn wood with the glass doors closed on a prefab fireplace?
No. Tempered-glass doors on a prefab like the RD-36 should be fully open during the burn and closed once the fire dies down. That is the standard for this type of appliance and it protects both the glass and the firebox.
Will doors made for other Superior 36-inch models fit my RD-36?
The RD-36 shares a door family with the BC36, BR36, HC36, and BBV36, but "same family" is not "same opening" after 30-plus years. A custom door built to your measurements fits right regardless of which sibling model you own.
Get Your RD-36 Doors Started Today
Configure your Superior RD-36 fireplace doors online in a few minutes and see your price instantly, or send a photo to the AI Fireplace Expert if you want a second opinion first. Prefer a human? Our fireplace specialists are available 7 days a week to check your measurements before anything goes into production. Either way, you get doors that fit your fireplace — not "close enough."