Lime Mortar

Why should we use lime mortar in today`s modern construction world?

There are many reasons why lime mortar is making a resurgence in the modern world of construction. Lime is a traditional binding material, which has been used for thousands of years for laying bricks, rendering and plastering before the introduction of Portland Cement. It is critical to differentiate been Portland Cement and lime in your brickwork, if you intend to make repairs (pointing) or extensions to your building. Never mix Lime with Cement, especially old brickwork as it was designed to have small amount movement. Most old brick built buildings are of a solid wall construction and very in thickness. Hydrated Lime can take a long time to harden, so very thick walls was used so they could build more than 3ft high every month.

Proven Over Centuries

Lime is one of the oldest forms of building materials used in the construction of buildings and can be dated as far back to the 4th century, you can still see today these landmarks due to their unique properties.

Allows Buildings To Breathe

Lime is less dense and more vapour permeable than cement based materials and does not trap water in the substrate which is the leading cause of decay in buildings. It will allow moisture to absorb and evaporate; which will cause less risk of salt and frost damage, while protecting the masonry.

Self Healing

Over time all buildings are subjected to degrees of movement over time. By not using cement will allow for small amount of movement and won’t develop individual large cracks like cement. Instead, it will dissolve when water is added and is redeposited into any tiny cracks which are formed.


Lime putty is the most common known lime in the industry, which is high purity dolomitic putty. The putty will be need to be slaked and screened, then left to matured for three months before it can be used. It can take several months or more for it to cure, depending on the humidity and temperature when laid.


Hydraulic lime is set by water. When water is added to the mix the lime will start to cure. Generally, you can laid it 1.5 linear metres per day depending on the weather conditions. This is the easiest form of lime to obtain and can be found in a ready mixed state or supplied on its own.

Old houses have to be treated with respect when working on them, due to the methods that were used to shape them. Lime mortar is considerably more expensive than cement, but if you do not use the correct original materials, the results will be far worse (Blown bricks, collapse walls). Old house`s have been constructed out of the simplest forms and generally don’t have foundations, concrete, damp proof course, wall ties and of course cement. However, these buildings are still standing today after 100 years, 200 years etc.


The main consensus for building in the last 60 years is to build strong, rigid build with little to no flexibility. So should there not be some give to flexibility and breathability in buildings?


Whatever your choice of binder, there are many reasons to use lime for aesthetics, range of colours, reduced movement joints, breathability and flexibility.