Cornerstone have been manufacturing Lime Putty since 1994 and they take great pride in the quality having earned a reputation within the industry as one of the leading manufacturers in the UK. Their Lime Putty is made using high calcium quicklime from Buxton, Derbyshire in the traditional method of storing in pits after slaking (adding to water). Their putty is matured for a guaranteed minimum period of four months and will have an approximate bulk density (RBD) of 1350kg/m3. It is important when ordering lime based materials to know the density of the lime putty; putty with a lower density will have a higher water content with less available lime. Therefore, additional lime could need to be added into the mortar.
Lime Putty in mortar, render and plaster: traditionally, the main use for Lime putty would have been in renders and plasters having been allowed to mature for a period of several months, or sufficient time to allow all the quicklime in the form of calcium oxide to fully convert to calcium hydroxide. Whereas traditional building mortars were made from quicklime and sand mixed together in a process we today call Hot Mixed Lime this was a simpler process which yielded a lime rich mix ideal for most aspects of masonry.
However, Lime Putty today is used for all aspects of construction, although some are clearly not appropriate for this material as its virtue can sometimes be its downfall, although there is no doubt that it produces the most vapour permeable of lime mortars. Cornerstone as one of the largest producers of Lime Putty in the UK recognise these issues and remain at our customers’ disposal to assist in the selection of the most appropriate materials for your project.
Putty when mixed with Sand, usually at a mix ratio of 1:3 or 2:5 will make a lime mortar. Hair, Fibres or Pozzolans can be added to the mix to modify certain characteristics of the mortar.