Commercial door hinge size is determined by three factors: door width, door height, and door weight. Standard 3’0” x 7’0” commercial doors use 4-1/2” x 4-1/2” standard-weight hinges, while wider and heavier doors require heavy-weight hinges. Most commercial interior doors require three hinges. Doors taller than 7’0” require a fourth hinge. This guide covers hinge sizing, hinge placement locations, the number of hinges required per door, weight ratings, and the differences between standard-weight, heavy-weight, and continuous hinges for commercial hollow metal and wood door applications.
CDF Distributors pre-punches hinge locations on all hollow metal frames at its Nashville, Tennessee fabrication facility. You can configure door, frame, and hinge selections online using CDF’s ProBuilder tool at cdfdistributors.com. For assistance selecting the correct hinge size or placement for your project, call (855) 769-9895 or email sales@cdfdoors.com.
Hinge Size by Door Width
Hinge size refers to the height and width of each hinge leaf, measured in inches. The correct hinge size depends primarily on the width of the door. Using an undersized hinge on a wide or heavy door creates excessive stress on the hinge knuckle and can cause premature wear, sagging, or binding. The following table shows the standard hinge size for each common commercial door width.
Nominal Door Width | Door Width (Exact) | Hinge Size |
2’0” (24”) | 23-3/4” | 4-1/2” x 4-1/2” |
2’4” (28”) | 27-3/4” | 4-1/2” x 4-1/2” |
2’6” (30”) | 29-3/4” | 4-1/2” x 4-1/2” |
2’8” (32”) | 31-3/4” | 4-1/2” x 4-1/2” |
3’0” (36”) | 35-3/4” | 4-1/2” x 4-1/2” |
3’6” (42”) | 41-3/4” | 4-1/2” x 4-1/2” |
4’0” (48”) | 47-3/4” | 4-1/2” x 4-1/2” |
The 4-1/2” x 4-1/2” hinge is the most common size in commercial construction because it corresponds to the standard 3’0” door width used in most interior applications. Doors 3’6” and wider may require larger, heavier weight hinges to support the additional door weight and leverage created by the wider leaf.
Number of Hinges Required per Door
The number of hinges on a commercial door is determined by door height. Insufficient hinges cause uneven weight distribution, which leads to hinge wear, door sagging, and difficulty latching. The table below shows the standard hinge count for each door height range.
Door Height | Number of Hinges |
Up to 5’0” (60”) | 2 hinges |
Over 5’0” to 7’0” (60” to 84”) | 3 hinges |
Over 7’0” | 4 hinges or more depending on height |
Three hinges is the standard configuration for commercial doors because the 7’0 door heights account for the majority of commercial interior openings. When a fourth hinge is required, it is typically positioned between the second and third hinge locations on the door.
When a door needs to be special ordered, CDF requires either an elevation drawing or a door machine schedule verified by the customer. This ensures that hinge and strike locations are confirmed before the order enters production. If hinge or strike placements are in question, the placement details must be added as a line item on the order so that CDF can verify locations before fabrication begins.
Standard-Weight vs Heavy-Weight Hinges
Commercial hinges are classified by weight capacity. Selecting the correct hinge weight rating is essential for door longevity and proper operation. An undersized hinge on a heavy door will fail prematurely, while an oversized hinge adds unnecessary cost. The following table compares standard-weight and heavy-weight hinge characteristics.
Characteristic | Standard Weight | Heavy Weight |
Typical Door Weight | Up to approximately 200 lbs | Over 200 lbs |
Common Applications | Interior offices, classrooms, storage rooms | High-traffic corridors, exterior doors, fire-rated openings |
Knuckle Construction | Standard knuckle with bearing surfaces | Reinforced knuckle, often with ball bearings |
Leaf Thickness | Standard gauge | Heavier gauge for increased load capacity |
Frequency of Use | Low to moderate traffic | High-frequency traffic (hospitals, schools, retail) |
Fire-Rated Assemblies | Acceptable for 20-min and 45-min rated openings (verify with AHJ) | Required for 60-min, 90-min, and 3-hour (180-min) rated openings per most codes |
For high-traffic commercial applications, heavy-weight hinges with ball bearings reduce friction and extend hinge life. Ball-bearing hinges are required on most fire-rated openings and on any door equipped with a door closer, because the closer adds continuous stress to the hinge pivots.
Continuous Hinges as an Alternative
A continuous hinge (also called a piano hinge) runs the full height of the door, distributing the door’s weight evenly across the entire hinge edge. Continuous hinges are an effective solution when standard hinge locations on a door and frame do not match, because the full-length hinge eliminates the need for individual hinge cutouts to align between door and frame.
Surface-mounted continuous hinges install on the face of the door and frame rather than requiring mortised hinge preps. This makes them useful for retrofit situations where an existing frame has nonstandard hinge locations. By using a surface-mounted continuous hinge, stock doors can be paired with existing frames without custom hinge preparation, reducing both cost and lead time.
Continuous hinges are available in aluminum and stainless steel, and in lengths that correspond to standard commercial door heights. CDF stocks an 83-inch continuous hinge for standard 7’0” door openings. Strike location still needs to match or be modified when using a continuous hinge.
Hinge Considerations for Wood Doors vs Metal Doors
Hinge placement requirements differ between wood doors and metal doors due to differences in how each door type is fabricated. Understanding these differences is important when selecting hinges and specifying hinge locations on an order.
Wood Doors
Wood doors offer more flexibility for hinge placement. CDF’s shop mortises hinge and strike locations into wood doors as they are ordered, meaning custom hinge placement can be accommodated without special tooling. Wood doors can also be cut down in height, and hinge and strike placements can be custom added by the shop after sizing. This flexibility makes wood doors easier to adapt to existing frames with nonstandard hinge locations.
Metal Doors
Metal doors are far less flexible. Hinge and strike locations on metal doors cannot be changed after fabrication. The doors are manufactured with specific hinge cutouts built in, and those locations must match the frame exactly. Metal doors cannot be cut down in width, and can only be cut down up to 4-7/8” in height. Because of these constraints, verifying hinge and strike locations before ordering a metal door is critical. An incorrect hinge location on a metal door typically requires reordering the door entirely.
Fire-Rated Hinge Requirements
Fire-rated door assemblies require hinges that meet specific performance criteria. All components in a fire-rated opening, including hinges, must be listed and labeled for the rating level of the assembly. The following table summarizes hinge requirements across all five commercial fire-rating levels.
Fire Rating | Frame Type | Door Type | Hinge Requirement |
20-minute | Drywall or masonry | Wood (standard core) or metal | Standard-weight steel hinges; must be listed for 20-min assembly |
45-minute | Drywall or masonry | Wood (mineral core) or metal | Standard-weight or heavy-weight steel hinges; must be listed for 45-min assembly |
60-minute | Drywall or masonry | Wood (mineral core) or metal | Heavy-weight ball-bearing steel hinges; must be listed for 60-min assembly |
90-minute | Drywall or masonry | Wood (mineral core) or metal | Heavy-weight ball-bearing steel hinges; must be listed for 90-min assembly |
3-hour (180-minute) | Masonry only | Metal only | Heavy-weight ball-bearing steel hinges; must be listed for 3-hour assembly |
Fire-rated doors must be self-closing and self-latching. Any door equipped with a closer places additional stress on the hinges, making ball-bearing hinges the standard choice for rated openings of 60 minutes and above. Drywall frames and wood doors cannot be rated beyond 90 minutes. Assemblies requiring a 3-hour (180-minute) rating must use masonry frames and metal doors.
All rated doors and frames must have a fire label riveted onto the assembly. A door or frame without a factory-applied fire label is not considered fire-rated, regardless of its construction. Verify all fire-rating requirements with project specifications and the Authority Having Jurisdiction (AHJ).
Hinge Backset
Hinge backset is the distance from the edge of the door to the center of the hinge knuckle (pivot point). Standard commercial hinge backset is 1/4”. The backset determines how far the door swings open and how it sits within the frame when closed. An incorrect backset can cause the door to bind against the frame or prevent it from opening a full 180 degrees when required.
Standard Hinge Backset | 1/4” |
Measurement | From door edge to center of hinge knuckle |
Effect of Incorrect Backset | Door binding, limited swing angle, or excessive gap at hinge edge |
Quick Reference: Hinge Selection Summary
The following table consolidates hinge selection criteria for the most common commercial door sizes into a single reference. Use this table to quickly determine hinge size, count, and weight class for a given door configuration.
Door Size (Nominal) | Hinge Size | Number of Hinges | Hinge Weight Class |
2’0” x 6’8” | 4-1/2” x 4-1/2 | 3 | Standard weight |
2’0” x 7’0” | 4-1/2” x 4-1/2 | 3 | Standard weight |
2’6” x 7’0” | 4-1/2” x 4-1/2 | 3 | Standard weight |
2’8” x 7’0” | 4-1/2” x 4-1/2” | 3 | Standard weight |
3’0” x 7’0” | 4-1/2” x 4-1/2” | 3 | Standard weight |
3’0” x 8’0” | 4-1/2” x 4-1/2” | 4 | Standard or heavy weight |
3’6” x 7’0” | 4-1/2” x 4-1/2” | 3 | Heavy weight |
3’6” x 8’0” | 4-1/2” x 4-1/2” | 4 | Heavy weight |
4’0” x 7’0” | 4-1/2” x 4-1/2” | 3 | Heavy weight |
4’0” x 8’0” | 4-1/2” x 4-1/2” | 4 | Heavy weight |
4’0” x 10’0” | 4-1/2” x 4-1/2” or larger. Check your specifications. | 4+ | Heavy weight |
For doors in high-traffic locations or doors equipped with closers, upgrade to heavy-weight ball-bearing hinges regardless of door weight. For fire-rated assemblies, verify hinge listings with the hardware supplier and the AHJ.
Verifying Hinge and Strike Locations on Orders
Incorrect hinge placement is one of the most common causes of field issues with commercial door installations. CDF’s order processing team verifies hinge and strike locations before production begins, but accurate information must be provided at the time of order. The following guidelines help prevent hinge placement errors.
- Anytime hinge or strike placements are in question, the placement details must be added as a line item on the order. This ensures CDF can verify hinge and strike locations before the order is finalized. If placement information is missing, CDF’s order processing team will flag the order before it enters production.
- When a door needs to be special ordered, CDF requires either an elevation drawing or a door machine schedule verified by the customer.
- All CDF stock doors and frames use Steelcraft-standard hinge and strike placements. If your project requires CECO, Curries, or other manufacturer-specific hinge locations, specify this at the time of order.
- On metal doors, hinge locations cannot be changed after fabrication. Double-check all dimensions before placing the order.
Configure Your Door and Hinge Assembly
CDF’s ProBuilder tool at cdfdistributors.com allows contractors and facility managers to configure complete door assemblies online, including hinge selection and placement. ProBuilder displays compatible hinge sizes and weight classes based on the door and frame configuration you select, and provides instant pricing for the complete assembly.
For assistance selecting the correct hinge for your project, call (855) 769-9895 or email sales@cdfdoors.com. CDF’s sales team is available Monday through Friday, 7:30 AM to 4:30 PM CT.
Frequently Asked Questions
What size hinges do I need for a 3’0” x 7’0” commercial door?
A standard 3’0” x 7’0” (36” x 84”) commercial door uses 4-1/2” x 4-1/2” hinges. This is the most common hinge size in commercial construction. Three hinges are required for a 7’0” door height.
How many hinges does a commercial door need?
Doors up to 5’0” tall require two hinges. Doors between 5’0” and 7’0” require three hinges. Doors taller than 7’0” require four hinges. More than four hinges may be required depending on the height of the door.
What is the difference between standard-weight and heavy-weight hinges?
Standard-weight hinges are designed for doors up to approximately 200 pounds in low to moderate traffic locations. Heavy-weight hinges have reinforced knuckles, heavier gauge leaves, and often include ball bearings. Heavy-weight hinges are required for high-traffic doors, heavier gauge doors, and for doors that are taller or wider.
When should I use a continuous hinge instead of butt hinges?
Continuous hinges are useful when standard hinge locations on a replacement door do not match the existing frame. Because a continuous hinge runs the full height of the door, it does not require individual hinge cutouts to align. Surface-mounted continuous hinges can be installed on stock doors and existing frames without custom mortising, saving time and cost on retrofit projects.
Can hinge locations on a metal door be changed after fabrication?
No. Metal door hinge and strike locations cannot be modified after fabrication. The hinge cutouts are built into the door during manufacturing. If a metal door is ordered with incorrect hinge locations, a new door must be ordered. This is why CDF requires verified elevation drawings or door machine schedules for all special-order metal doors.
Do fire-rated doors require special hinges?
Yes. All components in a fire-rated assembly must be listed and labeled for the fire rating of the opening. For 20-minute and 45-minute rated openings, standard-weight steel hinges are generally acceptable. For 60-minute, 90-minute, and 3-hour (180-minute) rated openings, heavy-weight ball-bearing steel hinges are typically required. Fire-rated doors must also be self-closing and self-latching, which means a door closer is always present, adding stress to the hinges. Verify hinge listings with the hardware supplier and the AHJ.
What hinge placement standard does CDF use?
All CDF stock doors and frames use Steelcraft-standard hinge and strike placements. CDF also stocks limited sizes in CECO and Curries placements. For special-order doors and frames with nonstandard hinge locations, CDF requires the hinge placement details to be included as a line item on the order and verified by the customer before production begins.
What is hinge backset and why does it matter?
Hinge backset is the distance from the edge of the door to the center of the hinge knuckle. The standard commercial hinge backset is 1/4”. An incorrect backset can cause the door to bind against the frame, prevent full swing, or create an uneven gap along the hinge edge. Backset is set during frame fabrication and is not adjustable in the field.
About This Guide
This reference guide reflects CDF Distributors’ standard specifications and industry knowledge developed through fabricating and shipping commercial door and frame assemblies from its Nashville, Tennessee headquarters. CDF’s fabrication team pre-punches hinge and strike locations on every hollow metal frame before shipping, ensuring precise alignment between door and frame components.
For questions about hinge selection, sizing, or placement, contact CDF at (855) 769-9895 or sales@cdfdoors.com. Configure your complete door assembly, including hinges, online at cdfdistributors.com using ProBuilder.
