Lime Products

 
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Hydraulic Lime or Non Hydraulic Lime

The first thing that is important to understand is the difference between Hydraulic Lime and Non Hydraulic Lime. The main difference is that hydraulic lime sets via hydrolysis which is the reaction with water whereas non hydraulic lime sets via carbonation which is a reaction with air.

Non Hydraulic Lime is softer and more flexible than it’s hydraulic counterpart and sets at a slower rate. Hydraulic Lime sets faster and is more durable, with similar properties to cement. This makes hydraulic lime ideal for exterior work as a lime render, especially when damp conditions are expected.

Lime Putty is another name for non hydraulic lime. Lime putty is made by the process of slaking which is the addition of water to quick lime.

Ecolime have developed our own unique slaking system which enables us to produce consistently perfect Lime Putty, free from impurities and contamination. Our Lime Putty is a highly refined Limestone based putty slaked from finely ground particles (90 microns – less than 1/10th of a millimeter) which results in a smooth putty that requires no sieving.

Lime putty does not set underwater and will only harden with exposure to the air in a process called re-carbonation.

Lime Plaster

This brings us to Lime Plaster, which as mentioned earlier is made up of sand, water and lime. The lime in question is usually Non-Hydraulic Lime, which of course is also known as Lime Putty. Incredibly, the use of Lime Plaster dates back as far as 7200BC where statues sculpted in Lime Plaster were found buried in a pit at the archaeological site of ‘Ain Ghazal in modern-day Jordan. This is a perfect example of just how durable Lime Plaster is as a building material.

Often products can be used as both a Lime Plaster and a Lime Render as the Lime Putty used is durable enough to withstand the weather conditions encountered in external use. This is just one of the many benefits of using lime plaster or lime render. Though this is dependent on climate and geographical location. For any help choosing the right lime plaster please do get in touch.

Benefits of Lime Plaster

  • Lime plaster is permeable and allows for the diffusion and evaporation of moisture.

  • Lime Plaster has a high pH which acts as a fungicide; meaning mold will not grow in lime plaster.

  • Plaster made from lime is less brittle and less prone to cracking than cement plaster and requires no expansion joints.

  • Lime plaster is less affected by water and will not soften or dissolve like drywall and earthen or gypsum plaster

  • Unlike gypsum or clay plaster, lime plaster is durable enough to be used as a lime render on the exterior of buildings.