Bitumen acts as the binding material, while asphalt is the final mixture of bitumen and mineral aggregates used for paving.

What Is Bitumen?

Bitumen is a dark, highly viscous hydrocarbon material commonly produced during petroleum refining. Its adhesive and waterproofing properties make it suitable for several industrial applications, with road construction being one of the most important.

In asphalt production, bitumen coats the mineral aggregates and binds them together. The properties of the selected bitumen can influence how the asphalt mixture behaves under traffic loads, temperature changes and environmental conditions.

What Is Asphalt?

Asphalt is a composite paving material produced by combining aggregates with a bituminous binder. The aggregates normally form most of the mixture by mass, while bitumen coats and binds the aggregate particles together.

The exact asphalt mix design depends on the intended application, traffic conditions, climate, aggregate properties and required pavement performance. As a result, asphalt should be understood as an engineered mixture rather than a single raw material.

Bitumen vs Asphalt: Key Differences at a Glance

Is Bitumen an Ingredient in Asphalt?

Yes. In conventional asphalt mixtures, bitumen acts as the binder that coats the aggregate particles and helps hold the mixture together. This is why bitumen quality and grade selection can influence important aspects of asphalt performance.

However, bitumen is only one component of an asphalt mixture. Aggregate gradation, aggregate quality, binder content, mix design, production conditions and compaction also affect the performance of the finished pavement.

How Much Bitumen Is Used in Asphalt?

Bitumen normally represents only a relatively small proportion of the total asphalt mixture by mass, while mineral aggregates make up most of the mix. However, the exact binder content depends on the asphalt mix design, aggregate characteristics, pavement layer, traffic conditions and required performance.

This is why there is no single bitumen percentage that applies to every asphalt mixture. The correct binder content is determined through mix design and laboratory evaluation rather than by using one fixed value for all road projects.

Which Bitumen Grades Are Used for Asphalt Production?

Different bitumen grading systems are used around the world to select binders for asphalt production. The appropriate grade depends on the applicable specification, climate, traffic loading, pavement design and project requirements.

Common categories include penetration grades such as 40/60, 60/70 and 80/100, performance graded (PG) binders and modified binders such as polymer modified bitumen (PMB).

40/60 vs 60/70 vs 80/100 Bitumen for Asphalt

Penetration grades are commonly identified by a penetration range measured under standardized test conditions. In general, a lower penetration value indicates a harder binder, while a higher value indicates a softer binder.

However, choosing between 40/60, 60/70 and 80/100 should not be based on grade numbers alone. The correct choice depends on the specification, climate, traffic level and pavement design.

For more detailed technical information, see Dejpa’s guides to Bitumen 40/60 , Bitumen 60/70 and Bitumen 80/100 .

How Does Climate Affect Bitumen Selection for Asphalt?

Temperature is one of the most important factors affecting binder behavior. At high pavement temperatures, bitumen becomes softer, while at low temperatures it becomes stiffer. The selected binder therefore needs to provide appropriate performance across the temperature conditions expected during pavement service.

This does not mean that one simple climate rule can replace the project specification. Traffic loading, pavement structure, mix design and the applicable grading system must also be considered when selecting a binder.

What Is PG Bitumen and Why Is It Used in Asphalt?

Performance Grade (PG) bitumen is classified according to the pavement temperatures under which the binder is expected to perform. Instead of relying primarily on conventional penetration values, the PG system evaluates binder behavior using performance-related testing.

This approach helps engineers select a binder according to expected high and low pavement temperatures and other project requirements.

For a detailed explanation of performance grades and their selection, see Dejpa’s PG Bitumen guide .

When Is Polymer Modified Bitumen Used in Asphalt?

Polymer modified bitumen (PMB) is produced by modifying conventional bitumen with polymers to achieve specific performance characteristics. It may be specified for pavements exposed to demanding traffic loads, temperature conditions or specialized performance requirements.

The exact benefits depend on the polymer system, binder formulation and project specification. PMB should therefore be selected based on defined engineering requirements rather than simply because it is a modified product.

For more information, see Dejpa’s guide to Polymer Modified Bitumen .

Bitumen vs Asphalt vs Tar: Are They the Same?

Bitumen, asphalt and tar are sometimes used interchangeably in everyday language, but technically they are different materials.

Which Term Should Buyers Specify: Bitumen or Asphalt?

The correct term depends on what is actually being purchased. If the requirement is for a binder to be used in asphalt production, the buyer should specify the required bitumen grade, applicable standard and technical properties.

If the requirement is for a finished paving mixture, the buyer should specify the asphalt mix design, aggregate requirements, binder type, target performance and any applicable project specification.

Why Does the Correct Bitumen Grade Matter for Asphalt Performance?

Bitumen is only one component of asphalt, but its properties can influence how the mixture responds to temperature, traffic loading and environmental conditions. A binder that is too soft, too stiff or otherwise unsuitable for the intended application may contribute to performance problems when combined with an inappropriate mix design or pavement structure.

For this reason, binder selection should follow the project specification and should be considered together with aggregate properties, mix design, production conditions, compaction and pavement design.

How Should Buyers Specify Bitumen for Asphalt Production?

A professional bitumen inquiry should provide more information than the grade name alone. Buyers should define the applicable specification, quantity, packaging, delivery requirements and any quality or inspection conditions that may affect the quotation.

This helps the supplier understand the actual procurement requirement and reduces the risk of comparing quotations prepared on different assumptions.

For a structured procurement checklist, see Dejpa’s guide to preparing a complete Bitumen RFQ .

Frequently Asked Questions About Bitumen and Asphalt

Are bitumen and asphalt the same thing?

No. Bitumen is the binder used to hold mineral aggregates together, while asphalt is the finished paving mixture made from aggregates and bituminous binder.

Is bitumen used to make asphalt?

Yes. In conventional asphalt production, bitumen coats and binds aggregate particles together and contributes to the mixture’s overall pavement performance.

What percentage of asphalt is bitumen?

There is no single percentage that applies to every asphalt mixture. Binder content depends on the mix design, aggregate properties, pavement layer, traffic requirements and project specification.

Is 60/70 an asphalt grade?

No. 60/70 is a penetration grade of bitumen. Asphalt is normally specified through a mix design and pavement performance requirements rather than by penetration grade.

Which bitumen grade is best for asphalt?

There is no universally best grade. The suitable binder depends on the project specification, climate, expected pavement temperatures, traffic loading, pavement design and the grading system being used.

Is tar the same as bitumen?

No. Petroleum bitumen and tar are different materials with different origins and properties. The terms should not be used interchangeably in technical specifications.

Can polymer modified bitumen be used in asphalt?

Yes. Polymer modified bitumen can be specified for asphalt mixtures where the project requires enhanced binder performance, but the appropriate formulation and specification should be selected according to the engineering requirements of the pavement.

Final Considerations

The simplest way to understand the difference is that bitumen is the binder and asphalt is the finished paving mixture. Although the two are closely connected, they should not be treated as interchangeable terms in technical procurement or project specifications.

For asphalt producers and infrastructure buyers, selecting the correct bitumen involves more than choosing a familiar grade. The applicable standard, climate, traffic conditions, pavement design and mix requirements should all be considered.

Clear terminology also improves procurement. Specifying the correct binder grade and technical requirement helps suppliers prepare more accurate technical and commercial offers and reduces the risk of product mismatch.