Hydraulic Lime Mortar

Hydraulic Lime Mortars are a blend of natural hydraulic lime (NHL 5, NHL 3.5 and NHL 2) and selected aggregates. They are highly workable and combine early set strength with long term flexibility and breathability. The mortars are available in three grades, HLM 5, HLM 2.5 and HLM 1 to suit various strength requirement


Hydraulic Lime Mortars are used for bricklaying, blocklaying and stone masonry work. HLM 1 mortar is typically used for internal use or for masonry work in sheltered areas and for work on soft bricks or delicate masonry, conservation and repair. HLM 2.5 mortar is used for repointing work and for masonry work in most locations. HLM 5 mortar is used for work in exposed areas such as chimneys, coping stones and canal/river work.


  • Manufactured from naturally occurring silicaceous and argillaceous limestone.
  • Breathable allowing the passage of air and moisture.
  • Highly workable and therefore easy to use.
  • Early set strength.
  • Long term flexibility and therefore less prone to cracking compared to cement mortars.
  • Reduced need for expansion joints due to flexibility.
  • Reabsorption of Carbon Dioxide from the air.
  • Mortar available on demand when supplied in silos.
  • Good to high resistance from sulphates.
  • Factory batch and quality controlled.

Product Downloads

Hydraulic Lime Mortar technical spec sheet
Hydraulic Lime Mortar Material Safety Datasheet
Hydraulic Lime Mortar

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