Cement

Cement

Cement is the backbone of modern construction, serving as an important binding agent in concrete and mortar. Different types of cement are available for various construction needs, each with unique properties and applications. 

What Are the Differences Between Type I, II and III Portland Cement?

Type I, II, and III Portland cement differ in composition and performance characteristics.

Type I

  • General-purpose cement is suitable for most construction jobs
  • Offers normal setting time and strength development
  • Commonly used in buildings, bridges and pavements

Type II

  • Provides moderate sulphate resistance
  • Develops less heat during hydration and is suitable for mass concrete structures
  • Often used in marine environments or where soil sulphate levels are high

Type III

  • High early strength cement, achieving higher strengths in shorter periods
  • Useful for cold weather concreting or when rapid form removal is needed
  • Generates more heat during curing, requiring careful temperature control

Cement vs Concrete: Which is Best? 

The choice depends on the application. Cement is used as a binder in mortars, grouts and specialised applications. It's ideal for thin applications or where a smooth finish is required, providing excellent adhesion. Also, it can be used to repair concrete surfaces. 

Concrete is a mixture of cement, aggregates and water, offering greater strength and versatility. It's suitable for structural elements, foundations and large-scale jobs, delivering better durability and load-bearing capacity than cement alone. 

How Long Does Cement Take to Dry?

Cement doesn't dry; it cures through a chemical process called hydration. The curing process follows the general timeline below.

  • Initial set occurs within 1-2 hours, allowing for finishing
  • Concrete reaches about 70% of its strength within 7 days
  • Full curing typically takes 28 days, though strength continues to increase over time

Several factors affect curing time. These include the water-cement ratio, ambient temperature and humidity, cement type, mix design and using accelerators or retarders.

What is the Best Cement for Repointing Brickwork?

A mortar mix with high lime content is often the best choice for repointing brickwork. Traditional lime mortars offer excellent breathability, which is crucial for older buildings. 

However, for modern structures, a mix of 1 part Portland cement to 4-6 parts fine sand works well. This blend provides a good balance of strength and flexibility. Always match the new mortar to the existing mortar's strength to prevent damage to the bricks. 

Our Best Mortar Mix for Repointing Brickwork guide will steer you in the right direction.

How Do I Determine the Best Cement Mix Ratio for My Project?

Determining the best cement mix ratio depends on several factors.

  • Application: Structural concrete requires different ratios than mortar or grout
  • Strength requirements: Higher cement content generally yields stronger concrete
  • Environmental conditions: Exposure to moisture, chemicals, or freeze-thaw cycles
  • Workability: Adjust the desired consistency ratio for placement and finishing

For general purpose, a 1:2:4 ratio (cement: sand: aggregate) is common. For higher strength, a 1:1.5:3 ratio may be used. Mortar uses a 1:3 or 1:4 cement-to-sand ratio.

Can I Return Cement Products?

Unfortunately, returns of powder-based products like ready mixed cement are not accepted. Cement requires specific storage conditions to maintain its quality. Once removed from proper storage, the shelf-life of cement is greatly reduced. 

To make the most of your cement orders, accurately estimate the amount needed for your project. Store unopened bags in a dry, cool place off the ground. Use opened bags promptly to ensure the best results. 

Read our Returns & Refunds page for more information.

Cement is the backbone of modern construction, serving as an important binding agent in concrete and mortar. Different types of cement are available for various construction needs, each with unique properties and applications. 

What Are the Differences Between Type I, II and III Portland Cement?

Type I, II, and III Portland cement differ in composition and performance characteristics.

Type I

  • General-purpose cement is suitable for most construction jobs
  • Offers normal setting time and strength development
  • Commonly used in buildings, bridges and pavements

Type II

  • Provides moderate sulphate resistance
  • Develops less heat during hydration and is suitable for mass concrete structures
  • Often used in marine environments or where soil sulphate levels are high

Type III

  • High early strength cement, achieving higher strengths in shorter periods
  • Useful for cold weather concreting or when rapid form removal is needed
  • Generates more heat during curing, requiring careful temperature control

Cement vs Concrete: Which is Best? 

The choice depends on the application. Cement is used as a binder in mortars, grouts and specialised applications. It's ideal for thin applications or where a smooth finish is required, providing excellent adhesion. Also, it can be used to repair concrete surfaces. 

Concrete is a mixture of cement, aggregates and water, offering greater strength and versatility. It's suitable for structural elements, foundations and large-scale jobs, delivering better durability and load-bearing capacity than cement alone. 

How Long Does Cement Take to Dry?

Cement doesn't dry; it cures through a chemical process called hydration. The curing process follows the general timeline below.

  • Initial set occurs within 1-2 hours, allowing for finishing
  • Concrete reaches about 70% of its strength within 7 days
  • Full curing typically takes 28 days, though strength continues to increase over time

Several factors affect curing time. These include the water-cement ratio, ambient temperature and humidity, cement type, mix design and using accelerators or retarders.

What is the Best Cement for Repointing Brickwork?

A mortar mix with high lime content is often the best choice for repointing brickwork. Traditional lime mortars offer excellent breathability, which is crucial for older buildings. 

However, for modern structures, a mix of 1 part Portland cement to 4-6 parts fine sand works well. This blend provides a good balance of strength and flexibility. Always match the new mortar to the existing mortar's strength to prevent damage to the bricks. 

Our Best Mortar Mix for Repointing Brickwork guide will steer you in the right direction.

How Do I Determine the Best Cement Mix Ratio for My Project?

Determining the best cement mix ratio depends on several factors.

  • Application: Structural concrete requires different ratios than mortar or grout
  • Strength requirements: Higher cement content generally yields stronger concrete
  • Environmental conditions: Exposure to moisture, chemicals, or freeze-thaw cycles
  • Workability: Adjust the desired consistency ratio for placement and finishing

For general purpose, a 1:2:4 ratio (cement: sand: aggregate) is common. For higher strength, a 1:1.5:3 ratio may be used. Mortar uses a 1:3 or 1:4 cement-to-sand ratio.

Can I Return Cement Products?

Unfortunately, returns of powder-based products like ready mixed cement are not accepted. Cement requires specific storage conditions to maintain its quality. Once removed from proper storage, the shelf-life of cement is greatly reduced. 

To make the most of your cement orders, accurately estimate the amount needed for your project. Store unopened bags in a dry, cool place off the ground. Use opened bags promptly to ensure the best results. 

Read our Returns & Refunds page for more information.