Understanding Lime Mortar and Its Benefits in Traditional Stonemasonry

In house mixed Lime Mortar pointing application

Lime mortar has been a cornerstone of traditional stonemasonry for centuries, prized for its versatility, durability, and compatibility with historic buildings. At Salthouse Stonemasonry, we are proud to craft all of our lime mortars directly from the source, ensuring the highest quality and authenticity for every project.

What Is Lime Mortar?

Lime mortar is a mixture of lime, sand, and water used to bond masonry units together. Unlike modern cement-based mortars, lime mortar offers flexibility and breathability, making it ideal for historic and traditional properties. It allows structures to move and "breathe," reducing the risk of cracking and preserving the integrity of the stonework.

Types of Lime Used in Mortar

There are several types of lime commonly used in mortar, each suited to different applications:

Hydraulic Lime:

• Contains natural clay impurities that enable it to set through a chemical reaction with water (hydraulic set).

• Ideal for areas exposed to moisture, such as external walls or below-ground masonry.

• Offers strength while retaining some flexibility.

  
  

  Non-Hydraulic Lime (also known as lime putty):

• Sets through a carbonation process, reacting with carbon dioxide in the air.

• Best for interior work and repairs to historic stonework.

• Extremely breathable and flexible, making it suitable for delicate restoration tasks.

  
  

  Feebly Hydraulic Lime:

• A middle ground between hydraulic and non-hydraulic lime.

• Provides moderate setting speed and strength, useful for areas requiring a balance of durability and breathability.

  
  

Benefits of Using Lime Mortar

Lime mortar offers several advantages, particularly for historic and traditionally built properties:

• Breathability: Lime mortar allows moisture to evaporate, preventing trapped water that can lead to damp and decay.

• Flexibility: Accommodates movement in buildings, reducing the likelihood of cracks and structural damage.

• Reversibility: Lime mortar can be removed and replaced without damaging the original stonework, making it ideal for restoration.

• Sustainability: Lime production has a lower carbon footprint compared to modern cement, and lime mortars can be recycled.

• Aesthetic Compatibility: The natural appearance of lime mortar blends seamlessly with historic stonework, maintaining the character of traditional properties.

  
  

Why We Make Our Own Lime Mortar

At Salthouse Stonemasonry, we believe in upholding the traditions of our craft. By sourcing and creating our lime mortar in-house, we maintain complete control over its quality and ensure it is perfectly suited to the unique requirements of each project. This hands-on approach allows us to honor the heritage of the buildings we work on while delivering exceptional results.

Lime mortar remains an essential element of traditional stonemasonry, offering unparalleled benefits for the preservation and maintenance of historic structures. Whether you're working on a centuries-old property or a new build inspired by classic techniques, understanding the types and advantages of lime mortar can make all the difference in achieving a lasting, authentic result.