When should hydraulic lime mortars be used?

When should hydraulic lime mortars be used?

Hydraulic lime mortar can be used for many applications. However, it is critical that the decision is decided in the early stages of the design and planning process. This will help all design and construction make the necessary adjustments to the work being carried out.

lime 25kg bags

New Build

lime mortar new build

Hydraulic lime mortars can be used in every aspect of new build construction and has additional structural benefits of modern cement building construction. Lime mortar has gained a wider acceptance in the construction of masonry walls.


Refurbishment using lime mortar

Generally, when refurbishment is undertaken it is usually considered as conservation, e.g. the repair and matching of mortars to the original joints of the building. They can also be used for construction of the extension or rebuilding of structures as a part of the refurbishment.


lime mortar conservation

Hydraulic lime mortar is commonly used in construction, as it is generally used for conservation and restoration of historic buildings. When using lime mortar for this, it is important to establish the composition of the original mortar. With regards to the binder and the aggregate previously used and to match the new mortar as closely as possible, so that there is no evidence that the original mortar has been detrimental to the masonry.

constraints using lime mortar


Hydraulic limes are not only used for construction of masonry walls, for example in the construction of walls using compacted hempcrete, limecrete floor slabs and external render and internal plastering.

Speed Of Construction

nhl 3.5 lime

Generally, the build rate when using lime mortar is perceived as being slow, when compared with cement mortars. Hydraulic lime mortars are generally not that slow to cement mortars. However, all lime based mortars develop their strength more slowly; but it is still possible to achieve acceptable build rates, particularly as bricklaying teams are experienced in the use of the mortars.

Gain Of Strength

hydraulic ashlar lime mortar

The compressive strength develops more slowly in lime mortars than in cement mortars. As a result, the compressive strengths of lime-based mortars are generally quoted at 91 days rather than 28 days.

Cold Weather Working

NHL 5 Hydraulic lime mortar

All masonry walls are susceptible to frost damage to whatever type of mortar used. This usually occurs after construction. Our web page Winter working conditions provide guidance on working in winter conditions. The development of the strength and durability of lime-based mortars is highly dependent on temperature, with little