In the world of construction and engineering, H-beam and I-beam steel are two of the most commonly used structural support elements.
Both beams offer unique advantages and characteristics, making them suitable for a wide range of applications.
The importance of selecting the right beam for your project cannot be overstated, as this decision can significantly impact the project’s structural integrity, cost, and overall success.
It is frequently asked how to choose between I-beam and H-beam, since they appear similar in shape.
However, many experienced individuals in the construction industry struggle to provide a clear explanation.
Here is a more in-depth explanation.
As evident from their shapes, H-shaped steel and I-shaped steel are distinct from one another, as illustrated in the following figure:

What Is I-beam Steel?

I-beam steel, as its name suggests, is a type of steel that has a cross-section resembling the letter “I. The inner surface of the top and bottom flanges of the I-beam are sloped, typically at a 1:6 ratio, making the flanges thin on the outside and thick on the inside.
This results in a cross-section with vastly different characteristics in the two main planes, making it difficult to fully utilize its strength in practical applications.
Despite the presence of thicker I-beams in the market, the I-beam’s structure inherently limits its resistance to torsion.
What is H-beam Steel?
H-section steel is widely used in today’s steel structure buildings due to its many differences compared to I-beams.
Firstly, the flanges of H-beam steel are equal in size and parallel, whereas the flanges of I-beam steel have an inclination, generally 1:6, making the outside thin and the inside thick.
Additionally, the cross-section characteristics of H-beam steel are significantly better than those of traditional I-beam, channel steel, and angle steel. This steel is named after the letter “H” due to its cross-section shape being similar to this letter.
It is an economical type of steel with a more optimized section area distribution and more reasonable strength-to-weight ratio. H-beam steel is sometimes referred to as W-beam, meaning wide flange beam.
The two outside beams of H-beam steel have no slant, making the welding of this steel simpler than that of I-beam.

H-beam steel has better mechanical properties per unit weight, which can result in a reduction of material and construction time.
The cross-section of I-beam steel offers superior direct pressure bearing and tensile resistance, however, its section size is too narrow to resist twisting.
On the other hand, H-beam steel is the opposite. Both I-beam steel and H-beam steel have their advantages and disadvantages.
Types of H Beam Steel
H-beam is divided into four categories, represented by the following codes:
Equal Flange H-beam (HP), with the section height equal to the flange width
Wide Flange H-beam (HW), with a wider flange than HP, represented by the letter “W”
Middle Flange H-beam (HM), with a flange width-to-height ratio in the range of 1.33 to 1.75, represented by the letter “M”
Narrow Flange H-beam (HN), with a flange width-to-height ratio greater than or equal to 2, represented by the letter “N”
HW, HM, and HN are all types of H-beam. H-beam is welded, while HW, HM, and HN are hot-rolled.
HW is mainly used for steel core columns in reinforced concrete frame structures, also known as stiffened steel columns. It is primarily used as a column in steel structures.
HM is mainly used as a frame beam in steel structures that bear dynamic loads, such as equipment platforms. The flange width-to-height ratio of HM is roughly between 1.33 and 1.75.
HN is mainly used as a beam. Its purpose is similar to that of I-beam. The flange width-to-height ratio of HN is greater than or equal to 2.
Translation into English:
Difference Between I-beam and H-beam(HW, HM, HN)
The flange of an I-beam has a variable cross-section, thicker near the web (the central vertical section), and thinner at the outside; while the H-beam has a uniform cross-section in the flange.
- Whether it’s a standard or light type, an I-beam, due to its relatively tall and narrow section size, has a significant difference in the moment of inertia of the two main axes of the cross-section. Therefore, it’s generally only suitable for bending components within the plane of its web or composing lattice-type force members. It’s not suitable for axial compression members or components that bend perpendicular to the web plane. This greatly limits its application scope.
- H-beam is a type of efficient and economic cut-section profile (others include cold-formed thin-wall steel, pressed steel plates, etc.). Due to their reasonable cross-sectional shape, they can make steel perform more efficiently and increase its bearing capacity. Unlike ordinary I-beams, the flange of an H-beam has been widened, and its inner and outer surfaces are usually parallel, which facilitates connection with high-strength bolts and other components. Its size constitutes a rational series with a complete range of models, facilitating design and selection.
- The flanges of H-beam are all of equal thickness. There are both rolled sections and composite sections welded from three plates. I-beams are all rolled sections. Due to different production processes, the inner edge of the flange has a 1:10 slope. The rolling of H-beam is different from ordinary I-beams, which only use a set of horizontal rolls. Because the flange of the H-beam is wider and has no slope (or a very small slope), an additional set of vertical rolls must be installed for simultaneous rolling. Therefore, its rolling process and equipment are more complex than ordinary rolling mills. The maximum rolled H-beam height that can be produced domestically is 800mm, anything beyond that would need to be a welded composite section.
Importance of Selecting the Right Beam for Structural Applications
The importance of selecting the right beam for structural applications cannot be overstated, as the choice significantly impacts the structural integrity, cost-efficiency, and overall success of a project.
Beams are essential in providing support and transferring loads in various structures, such as buildings, bridges, and industrial facilities.
Choosing the appropriate beam type for a specific application involves careful consideration of various factors to ensure optimal performance, safety, and durability.
Some reasons why selecting the right beam is crucial for structural applications include:
- Load-bearing capacity: The right beam ensures that the structure can adequately support the imposed loads without compromising its stability. Different beams have varying load-bearing capacities, making it essential to choose a beam that meets the specific requirements of the project.
- Structural integrity: Selecting the appropriate beam contributes to the overall structural integrity of a construction project, reducing the risk of failure or collapse. A well-chosen beam helps distribute loads efficiently and withstand various stressors, such as bending, shear, and torsional forces.
- Cost-efficiency: Choosing the right beam can lead to cost savings in terms of material usage, fabrication, and assembly. Selecting a beam that meets the project’s needs without being over-engineered can result in lower material costs and reduced labor requirements during installation.
- Adaptability: The right beam should offer flexibility in terms of design and adaptability to different project requirements. This includes the ability to accommodate changes in load distribution, connection methods, and environmental conditions.
- Aesthetics: Beams play a significant role in the overall appearance of a structure. Selecting a beam that complements the project’s architectural style and aesthetic requirements is essential to achieve a cohesive and visually appealing design.
- Compliance with building codes and regulations: Selecting the right beam ensures compliance with local building codes and regulations, which are in place to ensure the safety and stability of structures. Non-compliance can lead to legal consequences, project delays, and additional costs.
H Beams vs I Beams: Difference Explained
After the above explanation of H-beam and I-beam, it is now clear what these terms mean.
So, what distinguishes H-beam from I-beam?
Related reading: online H-beam & I-beam Weight Calculator

1. I-Beam’s Moment of Inertia and Limitations
The moment of inertia of the section is significantly different because the cross-section of an I-beam is relatively tall and narrow, regardless of whether it is an ordinary I-beam or a light-duty I-beam.
As a result, they are typically only suitable for parts that experience bending in the plane of the web or for forming lattice-type load-bearing parts.
However, they are not suitable for structural parts subjected to axial compression or parts that bend perpendicular to the plane of the web, limiting their application significantly.

2. H-Beam’s Efficiency, Economical Design, and Load Capacity
H-beam steel is a type of high-efficiency, economically-cut profile, along with other options such as cold-formed thin-walled section steel and profiled steel plates.
Its reasonable cross-section shape allows it to perform better and support higher loads.
In contrast to traditional I-beams, the flanges of H-beam steel are wider, and its inner and outer surfaces are typically parallel, making them stronger when connecting with high-strength bolts and other components.
Thanks to its variety of sizes and complete range of models, H-beam steel is convenient for design and selection, except for I-beam steel used for crane beams.

3. Manufacturing Processes: Roll-Forming and Welding Differences
The flanges of H-beam steel are of uniform thickness and are roll-formed. Additionally, H-beams feature a combined section made up of three plates that are welded together.
I-beams, on the other hand, are roll-formed sections. The inner edges of the inner flanges have a 1:10 slope, which is a result of the poor production techniques.
The rolling process for H-beam steel differs from that of regular I-beams, which use only one set of horizontal rolls. The wide flange and lack of slope (or very small slope) of H-beam steel require the use of a set of vertical rolls for simultaneous rolling, making the rolling process and equipment more complex than for standard rolling mills.
The maximum height of rolled H-beam that can be produced in China is 800mm, and if a higher height is needed, the H-beam must be welded.

4. Categorization of H-Beam Types and their Applications in China
In China, the national standard for hot-rolled H-beam steel (GB/T11263-1998) categorizes H-beam steel into three groups, identified as hz, hk, and hu respectively.
- narrow flange
- wide flange
- steel pile
The narrow-flange H-beam is ideal for use in beams or bending components, while the wide-flange H-beam steel and H-beam steel piles are best suited for axially-compressed structural components or bending components.
When comparing I-beam to H-beam steel with the same weight, the values of w, ix, and iy for the I-beam are not as favorable as those for H-beam steel.

5. I-Beam’s Limited Directional Force Resistance
The I-beam has a smaller length but a taller height and can only withstand force in one direction.

6. H-Beam’s Capability to Withstand Force in Two Directions
H-beam steel has a deeper channel, thicker cross-section, and is capable of withstanding forces in two directions.
7. I-Beam’s Inadequacy for Steel-structured Buildings
As the demand for steel-structured buildings increases, I-beams alone cannot fulfill this demand as even thicker I-beams are unstable when used in load-bearing columns.
8. Versatility of H-Beam in Load-bearing Applications
I-beams are limited to use as beams, whereas H-beam steel can be used for load-bearing columns.
9. H-Beam’s Enhanced Mechanical Properties and Lateral Stiffness
H-beam steel is an economical type of section steel that has better mechanical properties compared to I-beam. It is named for its cross-sectional shape, which resembles the letter ‘H’.
The flanges of hot-rolled H-beam steel are wider than those of I-beams and provide greater lateral stiffness and resistance to bending.
Additionally, H-beams are lighter than I-beams for the same specifications.

10. Differences in Flange Thickness of I-Beam and H-Beam
The flange of an I-beam is thick near the web and thin on the outer part, while the flange of H-beam steel is of equal thickness throughout the cross-section.
11. Terms and Types for H-Beam Steel: Welded and Hot Rolled
HW, HM, HN, and H are the common terms used for referring to H-beam steel. H-beam steel can be either welded or hot rolled, with HW, HM, and HN being the terms used for referring to hot rolled H-beam steel.

12. HW H-Beam’s Application in Reinforced Concrete Frame Columns
HW refers to H-beam steel that has roughly the same height and flange width. It’s primarily used as the steel core column in reinforced concrete frame columns and is also referred to as a stiff steel column. It is mainly used for columns in steel structures.
13. HM H-Beam’s Height-to-Width Ratio and Uses in Dynamic Loads
HM refers to H-beam steel with the ratio of the height to the width of the flange roughly ranging from 1.33 to 1.75.

HM refers to H-beam steel with a height-to-width ratio of flange of approximately 1.33 to 1.75. It is mainly used in steel structures, such as as a steel frame column or frame beam in a frame structure under dynamic loads, for example, in equipment platforms.
14. HN H-Beam’s Application Similar to I-Beam’s Use in Beams
HN refers to H-beam steel with a height to flange width ratio of greater than or equal to 2. It is mainly used in beams, similar to the usage of I-beam steel.
How Can I-Beam and H-Beam Be Distinguished?
Distinguish by appearance:
As its name implies, I-shaped steel is a section steel shaped like the letter “I.” The inside surface of the upper and lower flanges slopes inward, typically at a 1:6 ratio, making the flanges thicker on the inside and thinner on the outside.
H-section steel is an economical and high-performance profile with an optimized section area distribution and a more reasonable strength-to-weight ratio. It gets its name from its shape, which is similar to the English letter “H.

Distinguish by flange:
The flange of an I-beam is thick near the web and thin on the outside;
The flange of H-section steel is of equal thickness throughout.
Distinguish by steel trough:
The I-beam has a small side length and a large height, so it can only bear force in one direction;
The groove of H-shaped steel is deep and thick, and can withstand forces in two directions.
How Are I-Beam and H-Beam Classified?
Classification of I-beam:
I-beam is mainly classified into three types: ordinary I-beam, light I-beam, and wide flange I-beam.
It can also be divided based on the height to flange width ratio into wide, medium, narrow, and wide flange I-beam.
The specifications for wide and medium wide flange I-beam range from #10-60, meaning the height ranges from 10 cm to 60 cm.
The light I-beam has a narrow flange and thin web, resulting in a lighter weight compared to other types of I-beam at the same height.
The wide flange I-beam, also known as H-beam, is characterized by two parallel legs without an inclination on the inner sides. It is considered an economical section steel and is rolled on four-high universal mills, earning it the nickname “universal I-beam.”
Both ordinary I-beam and light I-beam have national standards established for them.

Classification of H-Section Steel:
(1) Based on the flange width of the product, it can be divided into wide flange, medium flange, and narrow flange H-beam.
The flange width B of wide flange and medium flange H-beam is greater than or equal to the web height H.
For narrow flange H-beam, the flange width B is about half of the web height H.
(2) According to its intended use, it can be classified into H-shaped steel beam, H-shaped steel column, H-shaped steel pile, and H-shaped steel beam with extremely thick flange.
Which of H-Beam Steel and I-Beam Steel Bears Better Load?
H-shaped steel is better suited for load-bearing.
Whether it is ordinary or light I-beam steel, due to its relatively high and narrow cross-sectional dimensions, the inertia moments of the two main axes in the cross-section differ greatly.
As a result, it can only be directly used for members subjected to bending in the plane of their webs, or it can be formed into lattice stress-bearing members.

It is not suitable for members subjected to axial compression or bending perpendicular to the plane of the web, limiting its scope of application.
On the other hand, H-section steel is an efficient and economical profile, thanks to its reasonable section shape, which enhances its effectiveness and improves its cutting capacity.
Unlike ordinary I-beams, the flange of H-beams is wider, and their inner and outer surfaces are typically parallel, making it easier to connect with other members using high-strength bolts.
Its size forms a reasonable series, and its models are comprehensive, making it convenient for design and selection purposes.

You can click the below link to download the steel beam load bearing calculator.
It’s Free.
Features of H-beam steel
The inner and outer sides of the flange of H-shaped steel are parallel or nearly parallel, and the end of the flange is at a right angle, making it known as the parallel flange I-beam.
The web thickness of H-shaped steel is smaller than that of an ordinary I-beam with the same height as the web, and the flange width is larger than that of an ordinary I-beam with the same height as the web, hence also referred to as the wide flange I-beam.
The shape of the H-beam results in improved section modulus, moment of inertia, and corresponding strength compared to an ordinary I-beam of the same weight.
When used in different metal structures, the H-beam exhibits superior performance in terms of bending moment, pressure load, and eccentric load, resulting in improved bearing capacity and the possibility of saving 10% to 40% of metal compared to an ordinary I-beam.

How to Calculate Load Bearing of I-Beam?
The bending bearing capacity formula is:
Mu=b’*h’*f*(0.5*h-0.5*h’)+(0.5*h-h’)*b*f*0.5*(0.5*h-h’)
F – design value of yield strength
b – web thickness
b ‘- flange width
h – high
h ‘- flange thickness
As for the bearing capacity of tension and compression, I think it is not necessary for me to explain here. As for eccentric tension and compression, it is not very difficult to calculate by yourself.
For example:
How much can I-beam #25 bear when the span is 4m and the load is evenly distributed?
Calculation:
For #25 I-beam, W = 401.4cm3, [σ]=210N/mm2, overall stability coefficient φb=0.93
Bending moment formula M = QL2/8
Strength formula σ = M/W
According to the formula:
q=8σW/L2=8*210*401400/4*4=42.1kN/m
Overall stability requirement: 42.1 * 0.93 = 39.2kn/m
Partial factor requirement (safety factor): 39.2 / 1.4 = 28kN/m
Safe use: 28kN/m
The above calculation does not consider the self weight and deflection checking calculation of I-beam.
What Are the Applications of I-Beam and H-Beam?
Purpose of I-beam:
Ordinary and light I-beams have relatively high and narrow cross-sectional dimensions, causing the inertia moments of the two main axes on the cross-section to differ greatly, limiting its range of application.
I-beams are not suitable for axial compression members or members subjected to bending perpendicular to the plane of the web, making their application scope limited.
Despite this, I-beams are widely used in building and other metal structures.

Purpose of H-beam:
Mainly used in various civil and industrial building structures, large-span industrial plants and modern high-rise buildings, particularly in areas with frequent seismic activity and under high-temperature working conditions.
H-beams are also used in large bridges with high bearing capacity, good section stability, and large spans, as well as in heavy equipment, highways, ship skeletons, mine support, foundation treatment and embankment engineering, and various machine components.
- Various civil and industrial building structures;
- Various large-span industrial plants and modern high-rise buildings, especially those in areas with frequent seismic activities and under high-temperature working conditions;
- Heavy equipment;
- Expressway;
- Ship skeleton;
- Various machine components.

What Are the Characteristics of I-Beam and H-Beam?
Characteristics of I-beam:
I-beam is characterized by its narrow flange, thin web, and light weight.
Characteristics of H-beam:
The H-beam has parallel or nearly parallel inner and outer flange sides, with a flange end at a right angle, which is why it is known as the parallel flange I-beam.
The web thickness of H-shaped steel is smaller than that of a regular I-beam with the same height as the web, and the flange width is larger than that of a regular I-beam with the same height as the web, making it also known as the wide flange I-beam.
The shape of the H-beam leads to a better section modulus, inertia moment, and corresponding strength than a regular I-beam of the same weight.
Factors to Consider When Choosing H-beam or I-beam Steel
A. Project requirements and constraints
One of the primary factors to consider when selecting the appropriate steel beam is the specific requirements and constraints of your project.
Factors such as load-bearing capacity, span length, and the type of connections needed will influence the choice between H-beam and I-beam steel.
For instance, H-beams are typically better suited for projects requiring greater load-bearing capacity and longer spans, while I-beams are more suitable for projects with weight constraints or those requiring narrower support structures.
B. Material availability and lead times
Material availability and lead times can also play a significant role in the decision-making process.
Depending on the size, quantity, and desired specifications of your beams, it may be more difficult or time-consuming to source one type of beam over the other.
In some cases, the lead time for obtaining custom-sized H-beams might be longer than that for I-beams, which could impact your project’s timeline.
It’s essential to consult with suppliers and fabricators early in the planning process to determine the availability and lead times for the required steel beams.
C. Architectural and aesthetic considerations
While structural performance is a top priority, architectural and aesthetic considerations should not be overlooked.
The visual appeal and design compatibility of the chosen beam can significantly impact the overall appearance of the finished project.
H-beams generally have a broader, more robust profile, making them an ideal choice for projects with an industrial or contemporary design aesthetic.
On the other hand, I-beams feature a slimmer, more streamlined appearance, which might be more suitable for projects with a traditional or minimalist design aesthetic.
D. Local building codes and regulations
Finally, it’s crucial to take into account local building codes and regulations when choosing between H-beam and I-beam steel.
Some jurisdictions may have specific requirements or restrictions on the types of structural support elements that can be used in certain types of construction projects.
It’s essential to consult with local authorities and engineering professionals to ensure that your choice of steel beam is compliant with all relevant codes and regulations.
FAQs
- What are H-beam and I-beam steel structures?
H-beams and I-beams are both structural steel shapes commonly used in the construction industry, mechanical engineering, and other applications that require strong support. H-beams have a wider flange and a thicker center web, resembling an “H” in cross-section, while I-beams have a narrower flange and a relatively thin center web, resembling an “I” in cross-section.
- How do the applications of H-beams and I-beams differ?
H-beams are mainly used for constructing tall buildings, bridges, and other structures requiring a high load-bearing capacity. Their wide flanges provide better stability and support against lateral forces. On the other hand, I-beams are used in smaller-scale projects such as residential construction, smaller bridges, and general fabrication work.
- What are the main advantages of H-beams?
The primary advantages of H-beams are their increased load-bearing capacity, greater stability, and resistance to bending. Their wider flanges and thicker center webs make them stronger than I-beams in terms of both compressive and tensile strength, making them suitable for heavy construction projects.
- What are the main advantages of I-beams?
I-beams have a lower weight per unit length compared to H-beams, which makes them more cost-effective and easier to transport and handle. They are also more efficient in handling vertical loads, making them ideal for smaller-scale projects and applications where weight and cost are important factors.
- Can H-beams and I-beams be used interchangeably in a project?
Although H-beams and I-beams have some similarities, they are not always interchangeable due to their differences in load-bearing capacity, stability, and weight. The choice between the two depends on the specific requirements of the project, such as the scale, load-bearing needs, and cost considerations.
- How do I choose between H-beam and I-beam steel for my project?
To choose the right structural steel shape for your project, consider factors such as the overall scale, load-bearing requirements, stability needs, and budget constraints. H-beams are typically more suitable for large-scale projects requiring high strength and stability, while I-beams are better for smaller projects where weight and cost are important considerations.
- Can H-beams and I-beams be welded together?
Yes, H-beams and I-beams can be welded together using appropriate welding techniques and materials. However, it is essential to ensure that the joined beams meet the load-bearing and stability requirements of the specific application. A structural engineer should be consulted to evaluate the suitability and safety of the welded connection.
- How do H-beams and I-beams compare in terms of corrosion resistance?
Both H-beams and I-beams can be prone to corrosion if exposed to harsh environments or aggressive chemicals. However, their corrosion resistance can be improved by using corrosion-resistant materials, coatings, or galvanization. The choice of material and protective measures depends on the application and environmental factors.
Very informative and technical comparison between the two steel sections which are most commonly used in the industry.
Glad to hear that and thanks for your comments.
As a historian who regularly deals with technology and industrial-related artifacts, I found this piece to be quite informative. Thank you. But a quick question…. I understand the structural differences between an H-beam vs an I-beam (i.e., tapered flanges on the I-beam), but is there an expectation regarding the width of the flange on an H-beam? Which, more specifically, is to ask if the flange needs to be as wide as the web is deep? Or can the flange width be less than the depth of the web? Thanks very much!
Well, the different types of H beam got different standard, for W-section, web:flange almost 1:1, for M-section, web:flange=1.33 – 1.75, for N-section, web:flange≥2. So, yes, flange can be less than the depth of the web.
im afraid the expanation ist not quite correct.
I-beam ist the definition of the din (germany) for many decades and replaced the older term doppel-t. its used for the closed calibre products and the open calibres as well. (paralell and sloped). the newer term “h” ist a european definition for the closed calibres, for the open calibres (sloped) remains the i-term (less important in use).
there is no connection between the shape of the letter and the shape of the form (sloped, paralell flanges).
for me the i-termination is the logical one for all series because theese beams are nearly for 99,9 % used as a “i” (upright), extremely seldom as a “h” horizontally because of the “widerstandsmoment” (don´t know the correct translation) ;-)
hello from cologne, thomas müller, dipl.-ing.
Thanks Thomas, hope your explanation can help more readers of this article.
Dear Sir
Im looking for H beam steel material alloy steel or recomended steel for manufacuring plat foarm for truck
heavy eweight
Our sales team will contact you.
#1. H beams are welded.
#2. I beams are not welded
#3. H beams are heavier
#4. I beams are lighter
#5. When the heavy H beams are used horizontally to support cantilevered concrete, unnecessary weight is being placed on the structures foundation which could create loading bearing issues in the foundation. While H beams are good for load bearing columns, they wreak havoc when used horizontally due to their sheer wieght alone.
Brian, many thanks for your kindly answer.
Building a small “over a creek” bridge. Width 12 feet. Crossing length 10 1/2 feet.
Need 2 I-beams 12 feet long by 2 to 3″ high, AND 5 crossing beams 10 1/2″ long by 4″ or 6″ high…topping will be 3″ x12″ wide x 12″ long center cut oak planks.
Your suggestions, and quote, please. Bob Heltman [email protected]
HI
WE WANT TO BUILD 16 MTR X 60MTR X 7 MTR HEIGHT SHEAD WITH H BEAM AND TRI -ANGLE
WHICH KIND OF H-BEAM AND ANGLE SUGGEST BY YOU.?
AND TOTAL HOW MANY KG STEEL NEEDED?
I am wanting to replace a header for a garage door (18’ door). Presently the header is 2” x 12” lumber sandwiched together.
It is 11.5” tall I need something 4” to 5” tall that will support the load.
I am thinking H or I beams
What are your thoughts??
We have to barns 45′ apart, we want to connect them with a roof only using a H-Beam 45′ long, what size H-Beam would we need ? It will carry trusses, lath & metal roofing.