With a wealth of projects under our belts, our team are experts in all things lime, and work extensively with clients based in Oxfordshire and across the Home Counties. When considering using lime-based products in your project, it’s certainly not a case of ‘one lime fits all’. There are two key types of lime product, each with distinct properties that should be taken into consideration before commencing your project.
Non-hydraulic lime, or lime putty as it’s more commonly known, is produced by burning limestone, resulting in ‘quicklime’. When the dry material is mixed with water, a reaction takes place, known as ‘slacking’. The resulting moist putty is then stored until required, typically for a number of months, during which time any remaining particles will slake themselves. Once exposed to air, the putty re-absorbs carbon dioxide and can set again. Due to the porous nature of non-hydraulic lime, it is considered the most suitable product to use when working with older buildings, where breathability is of the upmost importance.
In more recent years, the use of hydraulic lime has increased dramatically, especially as the preparation time is significantly less than that of its non-hydraulic counterpart. Produced from limestone containing clay, this type of lime sets as a result of a chemical reaction with water, but also partly via carbonation. Hydraulic lime can take many different forms, depending on the concentration of clay used to create them. Whilst the setting time of hydraulic lime is much quicker than that of non-hydraulic lime, this generally means it is less permeable, and therefore not always suitable for certain projects.
The advantages of utilising lime-based products in construction are undoubtedly vast, but making sure you choose the right kind of product is crucial to in order to reap the full benefits. If you are considering using lime, get in touch to find out how our team can work with you on your project, no matter how large or small, we are here to help!