Looking to expand your knowledge on I-beams? Whether you’re a construction professional or simply curious about the world of structural steel, our comprehensive guide to I-beams has everything you need to know about this essential building material.
From the different types of I-beams available to the importance of selecting the right size for your project, we cover all the key information you need to make informed decisions about your construction needs.
With our handy weight calculator and detailed size chart, you’ll have all the tools you need to ensure your I-beams are up to the task at hand.
So why wait? Dive into our article today and discover the world of I-beams like never before!
What is I beam?
As we all know, there are many types of I-beams, including ordinary I-beams and light I-beams. Due to their relatively high and narrow cross-sectional dimensions, the difference in the moment of inertia between the two main flanges is quite large.
Therefore, they can only be used directly for components that bend within the plane of their web or as lattice-type structural members.
They should not be used for axial compressive members or components with bending perpendicular to the plane of the web. This greatly limits their application range.

I-beam steel is a type of steel with an appearance of an I-shaped letter. It is commonly used in the construction industry.
The flanges of the I-beam are of equal thickness and have rolled sections. They can also be made of combination sections welded from three plates.
Usually, I-beams are made of rolled sections, and due to poor production technology, the inner edge of the flange has a slope of 1:10.
The rolling process of I-beams is different from that of common I-beams, which only uses a set of horizontal rollers. Due to the wide flange and no inclination, a set of vertical rollers must be added to roll it at the same time.
Therefore, its rolling process and settings are more complicated than those of ordinary rolling mills. The maximum height of H-beams that can be produced in China is 800mm, exceeding the limit of only using welded combination sections.
When cutting and welding I-beams and their homogeneous products, employees holding construction steel structure welding skills certificates must be appointed, and relevant national construction steel structure standards must be strictly followed.
When using flame cutting for I-beam steel, the web should be cut first before cutting the flange to avoid stress becoming cracks.
If necessary, the cutting position should be preheated with a cutting flame to a preheating temperature of ≥200℃ before cutting.
The cutting corners should be transitioned with a rounded arc, and the radius of the arc should not be less than 25mm.
After the I-beam steel is cut, the cutting position should be immediately tapped with a welding chisel to remove stress.
I-beams, also known as universal beams, are steel beams with an I-shaped cross-section. They come in two types: standard I-beams and lightweight I-beams.
I-beams are a type of structural steel that features an I-shaped cross-section.
Related reading: H-Beam vs I-Beam Steel: Which One Should You Choose?
Types of I-beam steel
I-beams are categorized into three types: ordinary I-beams, light I-beams, and wide flange I-beams.
The categorization is further based on the height ratio of the flange to the web, resulting in wide, medium, and narrow flange I-beams.
Ordinary and light I-beams have a height range of 10 cm to 60 cm, as indicated by the #10-60 specification. Light I-beams have a narrow flange, a thin web, and are lighter compared to ordinary I-beams.
Wide flange I-beams, also known as H-beams, are distinguishable by their two parallel legs and the lack of an incline on the inner side of the legs.
These beams belong to the economic section steel and are produced on a four-high universal mill, hence referred to as “universal I-beams”.
Both ordinary and light I-beams have established national standards for them.
Application of I-beams:
- Beam and column components in steel structures for industrial and civil buildings;
- Steel bearing supports for industrial structures;
- Steel piles and support structures for underground engineering;
- Industrial equipment structures such as petrochemicals, electricity, etc.
- Large-span steel bridge components;
- Shipbuilding and mechanical manufacturing frame structures.
Importance of choosing the right I-beam size
In the design of building structures, selecting the appropriate size of the I-beam is crucial because different I-beams have different load-bearing capacities and stability.
Therefore, when choosing an I-beam, factors such as the size of the load to be carried, and the height and span of the building structure need to be taken into consideration.
Only by correctly choosing and using I-beams can the building structure remain stable, safe, and sturdy.
I beam weight calculator

Note:
If you need to convert I-beam sizes from millimeters to inches, you can use our millimeter to inch conversion calculator for precise results.
I beam size & weight chart
It is advisable to watch the accompanying video before calculating the weight of an I-beam for a better understanding of the procedure.
The provided chart can be used as a reference guide for the dimensions and weight of I-beams.
Ordinary Hot Rolled I Beam Sizes & Weight Chart
Spec. | Height (mm) | Flange Width (mm) | Web Thickness (mm) | Theoretical Weight (kg/m) |
---|---|---|---|---|
10 | 100 | 68 | 4.5 | 11.261 |
12.6 | 126 | 74 | 5 | 14.223 |
14 | 140 | 80 | 5.5 | 16.89 |
16 | 160 | 88 | 6 | 20.513 |
18 | 180 | 94 | 6.5 | 24.143 |
20a | 200 | 100 | 7 | 27.929 |
20b | 200 | 102 | 9 | 31.069 |
22a | 220 | 110 | 7.5 | 33.07 |
22b | 220 | 112 | 9.5 | 36.524 |
25a | 250 | 116 | 8 | 38.105 |
25b | 250 | 118 | 10 | 42.03 |
28a | 280 | 122 | 8.5 | 43.492 |
28b | 280 | 124 | 10.5 | 47.888 |
32a | 320 | 130 | 9.5 | 52.717 |
32b | 320 | 132 | 11.5 | 57.741 |
32c | 320 | 134 | 13.5 | 62.765 |
36a | 360 | 136 | 10 | 60.037 |
36b | 360 | 138 | 12 | 65.689 |
36c | 360 | 140 | 14 | 71.341 |
40a | 400 | 142 | 10.5 | 67.598 |
40b | 400 | 144 | 12.5 | 73.878 |
40c | 400 | 146 | 14.5 | 80.158 |
45a | 450 | 150 | 11.5 | 80.42 |
45b | 450 | 152 | 13.5 | 87.485 |
45c | 450 | 154 | 15.5 | 94.55 |
50a | 500 | 158 | 12 | 93.654 |
50b | 500 | 160 | 14 | 101.504 |
50c | 500 | 162 | 16 | 109.354 |
56a | 560 | 166 | 12.5 | 106.316 |
56b | 560 | 168 | 14.5 | 115.108 |
56c | 560 | 170 | 16.5 | 123.9 |
63a | 630 | 176 | 13 | 121.407 |
63b | 630 | 178 | 15 | 131.298 |
63c | 630 | 180 | 17 | 141.189 |
Light Duty Hot Rolled I Beam Sizes & Weight Chart
Spec. | Height (mm) | Flange Width (mm) | Web Thickness (mm) | Theoretical Weight (kg/m) |
---|---|---|---|---|
8 | 80 | 50 | 4.5 | 7.52 |
10 | 100 | 55 | 4.5 | 9.46 |
12 | 120 | 64 | 4.8 | 11.5 |
14 | 140 | 73 | 4.9 | 13.7 |
16 | 160 | 81 | 5 | 15.9 |
18 | 180 | 90 | 5.1 | 18.4 |
18a | 180 | 100 | 5.1 | 19.9 |
20 | 200 | 100 | 5.2 | 21 |
20a | 200 | 110 | 5.2 | 22.7 |
22 | 220 | 110 | 5.4 | 24 |
22a | 220 | 120 | 5.4 | 25.8 |
24 | 240 | 115 | 5.6 | 27.3 |
24a | 240 | 125 | 5.6 | 29.4 |
27 | 270 | 125 | 6 | 31.5 |
27a | 270 | 135 | 6 | 33.9 |
30 | 300 | 135 | 6.5 | 36.5 |
30a | 300 | 145 | 6.5 | 39.2 |
33 | 330 | 140 | 7 | 42.2 |
36 | 360 | 145 | 7.5 | 48.6 |
40 | 400 | 155 | 8 | 56.1 |
45 | 450 | 160 | 8.6 | 65.2 |
50 | 500 | 170 | 9.5 | 76.8 |
55 | 550 | 180 | 10.3 | 89.8 |
60 | 600 | 190 | 11.1 | 104 |
65 | 650 | 200 | 12 | 120 |
70 | 700 | 210 | 13 | 138 |
70a | 700 | 210 | 15 | 158 |
70b | 700 | 210 | 17.5 | 184 |
I beam sizes chart PDF download
Choosing the Right I-Beam Size
Factors to consider when selecting the right I-beam size
When choosing I-beams, it is necessary to pay attention to their quality. Although similar types of steel are available on the market, there are significant differences in material and processing technology that can result in large variations in quality.
Moreover, many projects require a large quantity of steel, so it is important to choose high-quality products. What are the characteristics of high-quality I beam steel?
No Surface Defects
Because during the processing of I-beams, the quality control of processing has to be started. The surface of high-quality products must be smooth and free from any cracks. There should be no scars, ears, or other impurities.
At the same time, special attention should be paid to physical comparison. The depth of some small scratches and pockmarks cannot exceed 0.1MM, otherwise it will affect later use.
Requirements for Low Magnification Structure
When purchasing this type of steel, it is important to pay attention to the requirements for low magnification structure. The cross-section should not have air holes, delamination, or other defects. If there are any issues with transportation or centering during production, the magnification level cannot exceed 1.5 and the total level cannot exceed 4.
Non-metallic impurities
If there are certain amounts of waste metal impurities in the material of I-beam steel, it will definitely affect its overall quality. It is necessary to determine the basic composition and ratio of the steel, and if it cannot meet the requirements for use, such steel should not be chosen. Before purchasing, multiple comparisons must be made.
Principles of selecting I-beam steel
With the widespread application of various equipment, the selection of I-beams for equipment foundations has become increasingly important and frequent.
The equipment foundation I-beam is a material used to support and bear the weight of the equipment foundation, characterized by stable quality, high strength, durability, etc.
Therefore, in the selection of equipment foundation I-beams, the following principles need to be followed:
Selection based on workload
Equipment foundation I-beams play an important role in bearing the weight of equipment, so the selection should be based on the workload of the equipment.
Generally, industrial equipment with large weights requires high-performance and high-quality I-beams that have undergone steel material strength testing.
For equipment with smaller loads, ordinary I-beams can be used.
Selection based on working temperature
The physical properties of I-beams differ at different working temperatures. High-temperature steel should be selected when working in high-temperature environments to ensure its strength and stability.
Conversely, low-temperature steel should be selected in low-temperature environments to avoid brittle fracture.
Selection based on corrosion resistance
The environment in which equipment foundation I-beams are used is usually harsh, with factors such as acid and alkali corrosion and corrosive gases.
Therefore, when selecting materials, the corrosive substances in the equipment’s environment should be considered, and materials with good corrosion resistance should be chosen, such as stainless steel or special alloy steel.
Selection based on construction conditions
When constructing the equipment foundation I-beams, appropriate models and sizes should be selected based on the site’s environment and conditions, including selecting the length and shape of the top and bottom foundation I-beams and choosing the size of the installation hole.
At the same time, the difficulty of on-site construction, personnel and equipment safety, and other factors should also be considered to ensure smooth installation and construction.
Overall, the selection of equipment foundation I-beams is determined by multiple factors such as the equipment’s working environment, workload, and construction conditions. Engineers and designers need to conduct a reasonable analysis and selection based on different situations to ensure equipment stability, durability, and safety.
Calculation of loads and stresses
For example:
As an example, let’s find the maximum load capacity of an I-beam #25 with a 4-meter span and an evenly distributed load.
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
Therefore, the safe use load capacity of the I-beam is 28kN/m.
Note that the calculation above doesn’t consider the self-weight and deflection calculations for the I-beam.
I-Beam Production Process
First, the steel plate is pre-treated, and the parts are cut, corrected, and processed according to the design drawing’s section division.
Then, the individual components are cut, assembled, and welded. After correction, the high-strength bolt holes are marked and drilled. The main beam, middle beam, horizontal beam, and other components are assembled into structural units, completing the production of unit components.
Then, in the factory, the tire frame is assembled by overall matching and assembly, aligning the screw holes of the mating plates with the drilled holes, positioning them with positioning pins, and fixing the mating plates to the undrilled components using spot welding before disassembly followed by drilling.
Pre-assembly technology is a link between manufacturing accuracy and bridge erection accuracy, which is an essential key process.
Pre-assembly should simulate the actual bridge erection situation, and the pre-assembly process is the process of checking the connection between various connecting components and also the means of checking the pass rate of the high-strength bolt hole group.
Under the premise of ensuring the external dimensions, the pass rate of the high-strength bolt hole group is guaranteed.
The main structural form of the I-beam composite beam is a large cross-section I-beam, consisting mainly of main beams, side beams, end crossbeams, middle crossbeams, lateral connections, and mating plates.
The main material of the I-beam is Q345D steel, with a beam height of 2050mm, and the longest I-beam is 34220mm.
After the steel beam is manufactured in the factory, individual I-beams such as main beams and side beams, along with mating plates and high-strength bolts, are sent to the installation site for overall assembly and installation.
Each span uses four pieces of steel I-beams, consisting of two outer main beams and two inner main beams.
The width of the composite beam bridge deck is 12.22m, with a steel beam height of 2.05m and a beam spacing of 3.3m. The steel main beams are made of Q345D I-shaped straight belly plate steel beams, welded by upper flange plates, lower flange plates, and web plates.
The flange plates and web plates are variable thickness steel plates, and high-strength bolts are used to connect the main beams at the construction site.
After surface treatment, all exposed surfaces of the steel beams are coated with primer, intermediate paint, and topcoat paint, and the painting scheme is chosen according to the protection period (15-25 years).
Aluminum spray coating is used on the friction surface. After the steel plate’s surface is treated using sandblasting rust removal technology, the surface roughness needs to reach Ra2.5.
Aluminum spray coating is used on the friction surface, and the coefficient of friction is not less than 0.4.
FAQs
1. What is an I Beam?
A: An I Beam is a structural element commonly used in civil engineering and construction projects. It is a long, horizontal element made from steel or other materials, with a cross-section resembling the capital letter “I.” The I Beam’s design provides both high bending and shear strength, making it ideal for supporting heavy loads.
2. What is the purpose of an I Beam size and weight chart?
A: An I Beam size and weight chart is a reference guide that provides essential information about I Beams, including their dimensions, weight per unit length, and sectional properties. This data enables engineers, architects, and construction professionals to select the appropriate I Beam for their specific project requirements.
3. How are I Beams sized?
A: I Beams are typically sized according to their nominal depth (height) and weight per unit length. The depth is measured from the top flange to the bottom flange, while the weight per unit length is expressed in pounds per foot or kilograms per meter. Commonly used sizing systems include the American Institute of Steel Construction (AISC) and the International Organization for Standardization (ISO).
4. What are flanges and web in an I Beam?
A: The flanges are the horizontal top and bottom parts of an I Beam, while the web is the vertical, central section that connects the two flanges. Together, these components create the I-shaped cross-section that gives the I Beam its strength and stability.
5. How do I choose the right I Beam for my project?
A: To select the appropriate I Beam for your project, you must first determine the required load-bearing capacity, span, and support conditions. This information can be obtained through engineering analysis, design codes, and standards. Next, consult an I Beam size and weight chart to find a beam that meets your specific requirements. Finally, consider additional factors such as material type, corrosion resistance, and cost before making your final selection.
6. Can I customize the size of an I Beam?
A: Yes, you can customize the size of an I Beam by working with a steel fabricator or manufacturer. Custom I Beams can be designed to meet unique project requirements, including non-standard dimensions and complex geometric shapes. However, custom beams may be more expensive and require longer lead times compared to standard sizes.
7. How much does I-beam weight per foot?
The weight of an I-beam per foot depends on its dimensions and the type of material it is made from, typically steel. A rough estimate for steel would be between 10 and 50 lbs per foot, but this can greatly vary depending on the specific size and type of I-beam.
8. How do you calculate I-beam weight?
To calculate the weight of an I-beam, you need to use the formula: Weight = Volume x Density. The volume is calculated by multiplying the cross-sectional area of the beam by its length, and the density for steel is typically 490 pounds per cubic foot. Therefore, if you know the dimensions and the length of the I-beam, you can calculate its weight.
9. How much does an I-beam weigh?
The weight of an I-beam varies greatly based on its dimensions and length. For example, an 8-inch, 10-pound steel I-beam weighs approximately 10 pounds per foot, so a 20-foot beam would weigh 200 pounds. Always refer to the manufacturer’s data or a steel beam weight chart for specific I-beam weights.
10. Why are I-beams so strong?
I-beams are strong because of their unique ‘I’ shape, which provides resistance to bending and shearing forces. The vertical section, or ‘web’, resists shear forces, while the top and bottom sections, or ‘flanges’, resist most of the bending moment. This efficient use of material makes the I-beam strong and lightweight compared to a solid rectangular or square beam of the same material.
11. What is the difference between I-beam and H beam?
The main difference between an I-beam and an H-beam is the shape of their flanges. I-beams have tapered flanges with a slope on the inside surface, while H-beams have flanges that are equal in width from top to bottom. This gives H-beams a more square appearance, while I-beams are more distinctly ‘I’-shaped.
12. What is stronger H beam or I-beam?
The strength of a beam is not solely determined by its shape but also by its material, size, and how it’s loaded. However, due to their shape, H-beams generally have a larger area, which can make them stronger in terms of load-bearing capacity. But in some applications, the tapered flanges of I-beams can make them more suitable.
13. What shape of beam is strongest?
The I-beam is one of the strongest shapes for a beam, which is why it’s commonly used in construction and engineering. Its unique ‘I’ shape efficiently handles both bending and shear forces. However, the strongest shape also depends on the specific application, load, and material properties.
14. What are the standard sizes of I-beams?
The standard sizes of I-beams in the US are identified by their depth and weight per foot, given in inches and pounds respectively. Common sizes include W8x10, W10x12, W12x14, and so on, where the first number represents the depth (height) of the I-beam and the second number represents the weight per foot. However, there are many sizes available, and custom sizes can also be produced.
This is very informative
Thanks.
You’re welcome.
Wanting to lift 500kg with girder trolley on an Hbeam 6 metres long
What size of i beam should i get
What size of h beam should i get
6 inch*6inch I section
400 feet
Hello, my name is Nelson:
I want to build a 2 ton gantry with a span of 10 ft. How tall and thickness does an I beam has to be.
Good morning
i Whant to build a 5 ton single Girder gantry crane, what size I beam should i need for the top main beam and what size beam can i use for the legs.
thank you in advance
Jimmy
Hi can youmplease help. I am building Root cellar 20ftx30ft and on top of it a church for 150people including children can you please give me idea what Ibeam or Hbeam should I used on the rootcellar that can also carry a worshipper 150 more or less? how many post Appreciate much your reply.
All the best
erlinda
[email protected]
What size I beam should.I want to lift 20 ton genset.
Nneed to calculate load carrying capacity of an I Beam Flange 4″ X Web 6″ thickness 8MM, Length 28′, vertically support structure? Thnx in advance