Hanson Castle Hydrated Lime may be used together with Hanson Castle cements to produce traditional cement: lime: sand mixes for mortars and renders. Hydrated lime being non-hydraulic is not suitable for use in mortars without cement being present. The principal benefit derived from hydrated lime in mortars is its effect of improving the workability and water retention. Whilst the hydrated lime does improve these properties the maximum benefit is derived from the use of lime putty. To produce lime putty, hydrated lime is gradually added to water, in a clean container, with constant stirring to form a paste. The paste is then allowed to condition by standing for at least 24 hours.