Guide to Commercial Door Slab Sizes
In commercial design and construction, one important aspect must not be overlooked — door sizes. Having reliable information on industry standards and accurate door measurements is imperative for project planning and execution. Using incorrect dimensions may cause project delays and noncompliance issues, resulting in costly errors.
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Our guide on commercial door slab sizes consolidates industry-standard information and more.
Standard Commercial Door Sizes in the United States
Standard commercial door sizes are guided by regulatory bodies such as the International Building Code (IBC) and the Americans with Disabilities Act (ADA). For example, Section 1010 of the IBC and Section 404 of the ADA clearly specify appropriate commercial door dimensions and other specifications.
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Here is a summary of interior, accessible commercial door dimensions in the U.S.:
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Standard height: Minimum 80 inches
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Standard width: Minimum 32 inches and up to 48 inches
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Standard thickness: No specific door slab thickness requirements in either the IBC or the ADA
Note that the above applies to accessible interior commercial doors. Other specifications will apply for other types of doors and those that are not required to be accessible, such as storage closets. The same applies to the type of commercial building.
For instance, the IBC states that some commercial properties, like apartments and hotels, have different requirements. Dwelling or sleeping unit doors must have a minimum height of 76 inches. Additionally, the Facility Guidelines Institute guideline states that hospitals must have a minimum door width of 44.5 inches for patient bedrooms.
Door Height
Although 80 inches is the minimum door height, this measurement can vary based on the building's ceiling height and design preferences. Other typical door heights include:
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80 inches: Standard interior commercial door height
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84 inches: Typical for more modern commercial buildings
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96 inches: Used in upscale buildings with high ceilings
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120 inches: Used for specialty applications such as grand entrances
Door Width
The primary focus of a door's width is to accommodate varying levels of accessibility and foot traffic. Common widths used include:
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36 inches: Standard single, commercial door width
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42 inches: Typical for high foot traffic commercial buildings
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60-72 inches: Used for double, commercial doors that consist of two leaves
Door Thickness
While there is no standard door thickness, thickness affects a door's durability and hardware compatibility. General thicknesses can include:
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1-3/4 inches: Typical thickness for commercial doors
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2 inches and over: Used for niche applications such as acoustic or security
Custom Commercial Door Slab Sizes
Not all clients have or want standard-sized doors. Some commercial buildings prioritize visual appeal alongside functionality to help their business stand out.
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So, how do you meet a client's custom-sized door needs while complying with regulatory codes? Partner with a door distributor with custom door options. It is crucial to choose a reliable supplier that understands and adheres to IBC and ADA compliance codes.
Nominal vs Actual Door Slab Sizes
Understanding the difference between nominal and actual sizes is crucial when ordering materials.
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Nominal sizes are measurements rounded up to the nearest inch. For example, if the actual door width is 31 3/4 inches, then its nominal size is 32 inches. Actual sizes are typically slightly smaller than their nominal sizes. The extra space allows for clearance around the door so it opens and closes smoothly.
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When purchasing a commercial door slab, know its nominal size so it can properly fit into the intended rough opening.
How to Measure Commercial Door Slabs
When installing or replacing a commercial door, take accurate measurements of the door slab and other necessary components. This is the case regardless of whether you are working with a standardized or customized commercial door size.
We cannot assume standard sizes will always fit. Each project or building is open to individuality due to factors such as building age, renovations and custom architectural designs.
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This is a quick step-by-step guide on measuring commercial door slabs:
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Gather tools: Gather essential tools for removing and measuring the door slab. Tools can include a measuring tape, a note-taker, a level and a step ladder.
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Remove slab: If needed, remove the door slab from the hinges for easier access and measuring.
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Measure height: Measure the door slab from top to bottom, taking measurements on its left, middle and right points. Record the smallest measurement.
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Measure width: Measure the door slab from left to right, taking measurements on its top, middle and bottom points. Record the smallest measurement.
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Measure thickness: Measure the distance between the door slab's interior and exterior sides.
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Verify compliance: Refer to your measuring records in your note-taker. Using your notes, verify whether the slab complies with the IBC and ADA.
Note that if the entire unit requires replacement, additional measurements and steps will apply. For instance, you must account for the door frame, jamb and hardware.
Frequently Asked Questions
Refer to these FAQs about commercial door slab sizes if you have further questions.
What Are Standard Commercial Door Sizes?
Standard commercial door sizes are generally 80 inches in height and 32 inches in width. That said, commercial door dimensions can come in various shapes and sizes. This is where manufacturers must adhere to IBC and ADA guidelines to ensure the door's accessibility, functionality and safety around these standards.
How Thick Are Commercial Door Slabs?
Commercial door slabs are typically 1-3/4 inches thick. Neither the IBC nor the ADA has specific door slab thickness requirements for commercial doors.
Is a 30-Inch Door Slab Actually 30 Inches?
It depends. If 30 inches is its nominal size, then its actual size will be less than 30 inches. However, if its actual size is 30 inches, then yes, the door slab is actually 30 inches.
What Is the Rough Opening for a Commercial Door?
The rough opening of a commercial door is the unfinished, framed wall space where the door will be installed. Its measurements must consider the sizing of the door slab, frame and jamb for an accurate installation. As such, rough openings have slightly bigger dimensions to accommodate the additional door components.
Find the Right Commercial Doors for Your Project
Understanding commercial door slab sizes and industry standards is important to ensure project success. However, balancing project quality and efficiency can become overwhelming when planning, budgeting, communicating with clients and executing projects. Finding the right door supplier should be the least of your worries.
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DoorStop is a fourth-generation distributor of standard and custom commercial doors. Looking for custom hollow metal door slab sizes, different veneer door options or commercial interior door hardware? We can help. Our years of experience allow us to provide you with fast lead times without compromising quality.
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Contact us today to get started.
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