Pin Hinges

A pin hinge isn’t one product. It’s a design category. A butt hinge — also called a mortise hinge — is the most common hinge for doors, featuring two leaves connected by a pin, with one leaf attached to the door and the other to the door jamb. That central pin acting as a pivot is what makes it a pin hinge. The family runs from the standard butt hinges hung on nearly every interior door to full-length continuous hinges carrying heavy commercial slabs.

The choice comes down to three things: door weight, door width, and how often the thing gets used. Get those right and the door swings clean for decades. Get them wrong and you’re back fixing sag, bind, and a screwed-up jamb before the warranty’s cold.

When the door’s closed, only the pin is visible, making for a seamless appearance. That’s the butt hinge appeal — it disappears. These hinges are typically 6 inches or shorter and installed flush within a mortise. Full mortise butt hinges have both leaves flush with the door and jamb, while half mortise versions only recess one leaf.

Sizing and Material — Where Most Mistakes Happen

Size tracks door thickness. For standard interior doors at 1-3/8 inch, use 3.5-inch hinges; for exterior or solid doors at 1-3/4 inch, use 4-inch to 4.5-inch hinges. A heavy solid-core exterior door — the kind that earns its keep insulating against a Montana January — needs the bigger hinge or it’ll sag and start dragging the threshold by spring.

Material is the other half. Butt hinges are suitable for both interior and exterior doors. Interior versions are generally made of steel for cabinets and lightweight doors, while exterior models use stainless steel or brass for rust and corrosion resistance, supporting greater loads. On any entry door facing freeze-thaw and wind-driven moisture, that corrosion resistance isn’t a luxury — it’s the difference between a pin that swings and a pin that seizes.

The smaller pin hinges carried for light-duty work cover the common tee/pin sizes. Stainless and brass tee/pin hinges come in 1-inch, 1-1/2-inch, and 2-inch. Zinc tee/pin hinges run 1-1/2-inch, 2-inch, 2-1/2-inch, and 3-inch. The stainless and brass options earn their place on anything that sees weather; zinc is the workhorse for protected interior duty.

Door type	Door thickness	Recommended butt hinge
Standard interior	1-3/8”	3.5”
Exterior / solid core	1-3/4”	4” to 4.5”

For the certification side: ensure hinges are ANSI/BHMA graded — Grade 1 is the heavy-duty standard. That’s the number that tells you the hinge was built and tested for the cycle count a commercial or high-use opening throws at it.

Butt Hinge or Continuous — The Real Fork

Here’s the decision that matters once a door gets heavy or busy. For high-traffic or heavy doors over 200 lbs, use continuous hinges. Below that, a good set of butt hinges does the job. Commercial entry doors that swing all day are a different animal — ball-bearing hinges use ball bearings to reduce friction, minimizing wear by decreasing the contact area between moving surfaces. These are commonly chosen for high-traffic commercial doors and heavy outside doors for long-lasting, smooth operation.

The case for a continuous hinge is mechanical. On conventional hinges, opening and kick-back energy concentrate on a few inches of fastened reinforcing plate — with the top hinge handling 100% of the force. Continuous hinges bond the door and frame into an integrated, sag-free unit, and kick-back energy dissipates along the entire length of the door and frame, compared to a conventional hinge’s 4-1/2” to 5” at the top. Spread the load over 80-some inches instead of one knuckle and the door stops trying to tear itself off the frame.

There’s a sealing bonus that matters up here. Continuous pin and barrel hinges eliminate the gap between the door and frame, providing a weatherproof, rust-proof, tamper-proof barrier. On a heavily used exterior opening, closing that hinge-side gap means less cold air sneaking past the weatherstrip.

These run long. Standard lengths are 79”, 83”, 85”, 95”, and 119” for nominal door heights, with custom lengths available. And the continuous pin-and-barrel design carries serious weight without babying the frame: for 1-3/4” doors up to 48” wide, up to 400 lb at medium-frequency without frame or door reinforcement, and up to 600 lb at low frequency without reinforcement.

Push past the no-reinforcement range and the frame work starts. Up to 200 lbs, no door reinforcement is required. For doors between 200 and 300 lbs, a 16 gauge channel in the frame is required. For doors up to 600 lb at a max width of 4’0”, rivet nuts are required in the frame in addition to the frame reinforcement.

Installation flexibility is a quiet advantage. These hinges can be cut to length during installation. The unique mounting pattern allows cutting up to 6” from the bottom while still having double-row fasteners. If cut more than 13.5”, other modifications may be necessary.

The guts of a quality continuous hinge

The construction is straightforward and it’s why these last. A 14 gauge 304 stainless steel barrel with a 3/16” diameter 304 stainless pin and long-life nylon medical bearings. Some heavier series step up to a 1/4” diameter pin with nylon self-lubricating, medical-grade split bearings. The stainless pin delivers high tensile strength by forming a strong, free-moving unit — flexible and strong in abused openings.

Continuous hinges come in a few mounting styles worth knowing. A full surface hinge has its leaves installed on the face of the frame and the face of the door — handy for retrofit work. A full mortise hinge mounts on the door stile’s side and the inside of the frame side jamb, so only the pin and barrel is visible when the door is closed. The full-wrap versions add edge protection: the full wrap edge guard protects the inside and outside edge of the door, which is most exposed to damage when open.

For fire openings, the better continuous hinges carry their rating out of the box. These meet ANSI/BHMA 156.26 and are UL10C listed at 3 hours. Fire-rated out of the package — no extra parts to buy or install, no liability worries.

Spec	Pin & barrel continuous hinge
Barrel	14 gauge 304 stainless steel
Pin	3/16” or 1/4” 304 stainless
Bearings	Long-life nylon medical
Standard lengths	79”, 83”, 85”, 95”, 119”
Max door	1-3/4” thick, 48” wide
Load (no reinforcement)	400 lb medium-freq / 600 lb low-freq
Certification	ANSI/BHMA 156.26, UL10C (3 hr)

Frequently Asked Questions

What’s the difference between a pin hinge and a regular door hinge? There isn’t really a separate “regular” hinge — most common door hinges are pin hinges. A butt hinge, the most common hinge for doors, features two leaves connected by a pin, with one leaf on the door and one on the jamb, and when closed only the pin is visible. The pin is the pivot. Continuous hinges and ball-bearing hinges are variations built on the same pin-pivot idea for heavier or busier doors.

What size hinge do I need for an exterior door? Match it to thickness. For exterior or solid doors at 1-3/4 inch, use 4-inch to 4.5-inch hinges. A heavy entry door over 200 lbs is a candidate for a continuous hinge instead.

Should I use steel, stainless, or brass hinges? Depends where the door lives. Interior versions are generally steel for lighter doors, while exterior models use stainless steel or brass for rust and corrosion resistance, supporting greater loads. For any door taking weather and freeze-thaw cycling, go stainless or brass.

How do I keep someone from lifting an outward-swinging door off its hinges? Spec the right pins. For security on outward-swinging exterior doors, always specify non-removable pins. Security hinges make doors open outwards while preventing someone from taking down the hinges and the door to break in, using features like security tabs and non-removable pins.

When is a continuous hinge worth the extra cost over butt hinges? When the door is heavy or busy. For high-traffic or heavy doors over 200 lbs, use continuous hinges. The payoff is structural — it bonds the door and frame into an integrated, sag-free unit, with kick-back energy dissipating along the entire length instead of loading up the top knuckle on a conventional set.

Do I need to reinforce the frame for a continuous hinge? Not always. Up to 200 lbs, no door reinforcement is required. For doors between 200 and 300 lbs, a 16 gauge channel in the frame is required. Past that toward 600 lb, you’re adding rivet nuts and reinforcement.

How do I install a butt hinge correctly? Install by mortising the leaves flush into the door and frame. Mark placement, pre-drill, and keep the pin plumb so the door swings without bind. Periodically lubricate pins with lithium-based grease to keep operation smooth.