Up to 4.5"of 2300° Ceramic Wool & Glass Blanket

Illustration of a gun safe cut out on a white background

2.5" 2300° Ceramic Wool

2.5" applied seamlessly to the entire interior.

3/8" Solid Door Plate

2" Glass Blanket

2" is applied to the top and bottom of the safe, while 1" is applied to the door.

4 Gauge Body

Nearly 1/4" thick.

16 Gauge Steel Liner

Fully encases the entire interior.

When fire strikes, most gun safes don’t stand a chance. That’s because they’re lined with the same drywall (aka fireboard) found in your home’s walls, cheap material that crumbles and falls apart long before the flames die out.

Sturdy Gun Safe is different. We build every fire-lined safe with the exact same insulation used in industrial ovens and kilns which are designed to handle over 2,300°F of relentless heat. These materials don’t just “slow down” heat, they block it, holding their shape and strength even after being exposed to extreme temperatures. And we don’t skimp on it. Sturdy gives you more of this premium ceramic and glass insulation than most manufacturers. Thicker layers, denser coverage, and complete protection from top to bottom. While others cut corners to save costs, we pack in every inch of heat-blocking material your safe can hold without weak spots. Every inch of your safe — walls, door, top, and bottom — is packed with perfectly compressed insulation that won’t shift, sag, or leave gaps over time. A rugged 16-gauge steel interior liner helps compress and cover the insulation material. It also adds more strength, so your shelves won’t buckle under pressure like others anchoring shelving into drywall and thin felt.

The Finer Details:

  • Each right, left, and back wall, along with the door jambs, is packed with 2½ inches of 2300°F-rated, 8 lb. density ceramic wool, compressed to 2¼ inches
  • The top and bottom walls will have 2.5" of ceramic insulator and 2" of glass blanket, compressed to 4".
  • The door will have 2.5" of ceramic insulator and 1" glass blanket, compressed to 3".
fire gasket used on gun safes

Sturdy Fire Gasket

When fire hits, the weakest point on most safes is the door seal. If heat and smoke slip through that tiny gap, everything inside is at risk. That’s why we use the same sealing technology trusted in industrial ovens and kilns — places built to handle extreme, nonstop heat. Every Sturdy Gun Safe with fire lining features a UL-tested fire caulking and a precision-fit boiler gasket — not the cheap, one-size-fits-all gaskets most safes use.

Here’s what makes ours different:

  • Real fire defense: Our LCI Firestop Sealant can block fire, smoke, and moisture for up to 3 hours, and when temperatures rise, it expands up to eight times its size to form a complete seal.
  • More coverage = more protection: Our boiler gasket is twice as wide as the average competitor’s, giving you 2× the sealing power where it matters most — around the door.
  • Custom-fit seal: No two safes have exactly the same door clearance, so we custom-fit every gasket for a perfect seal right from the start. Competitors often use Palusol gaskets, which only expand after they get hot.