Non-hydraulic lime
England in 2008, defines non-hydraulic lime (or putty lime) as: ‘Lime which will not set by chemical reaction with water but requires exposure to carbon dioxide in the air in order to harden. Unlike hydraulic limes (see Hydraulic lime), it is derived from pure limestone. It is commercially available in powder (hydrated) or putty form.’
Short Guide, Lime Mortars in Traditional Buildings, published on 1 March 2013 by Historic Scotland, defines putty lime as a: ‘Hydrated lime binder that has been slaked with an excess of water forming a wet paste that can be left to mature over time.’
Society for the Protection of Ancient Buildings (SPAB) definition online Glossary defines lime putty as: 'Calcium hydroxide (Ca(OH)2) formed as a paste when a non-hydraulic or weak (NHL 2) hydraulic lime is slaked in an excess of water and the milky suspension is allowed to settle. Can also be made by mixing hydrated lime (the form widely available in builders' merchants) and water, although this gives a less workable mix with inferior plasticity and binding properties.'
See also: Hydraulic lime.
[edit] Related articles on Designing Buildings
Featured articles and news
A forward thinking, inclusive global community of members.
From engineered product life-spans, to their extension.
Circular economy in the built environment
A brief description from 2021. Where are we now?
Mental Health Awareness Week with ABS
Architects Benevolent Society programme of activity.
CLC publishes domestic retrofit competency framework
Roadmap of Skills for net zero.
May 13-19: Moving more for our mental health.
Understanding is key to conservation.
Open industry engagement survey seeks responses
Institutions and the importance of engagement.
National Retrofit Hub unveils new guide
Digital Building Logbooks and Retrofit: An Introduction.
Enhancing construction site reporting efficiency
Through digitisation and the digital revolution.
Noise in the built environment
BSRIA guide TG 20/2021.
17,000 people suffer conditions as a result of exposure to excessive noise at work.
Turning down the noise: Auditory health
A pervasive risk with far-reaching consequences.
Getting the most out of heat pumps and heating
How heat pumps work and how they work best.
Cost-of-living crisis and home improvement plans
Starting on the right footing and top tips for projects.
Electrotechnical excellence, now open for entries.