Hydrated lime
Short Guide, Lime Mortars in Traditional Buildings, published on 1 March 2013 by Historic Scotland, defines hydrated lime as: ‘Powdered lime formed from the slaking (addition of water) of quicklime. This term may be used in reference to hydraulic limes or air limes, but is typically used for the latter.’
Short Guide: Traditional Scottish Brickwork, published, on 1 March 2014 by Historic Environment Scotland, suggests that hydrated Lime: ‘Commonly used to describe non-hydraulic lime powder which is used in modern cement/lime/sand mortars. It is important to distinguish between this and hydraulic Lime which is the material most commonly used in lime mortar mixes in repair work.’
Society for the Protection of Ancient Buildings (SPAB) definition online Glossary : Hydrated lime or dry hydrate
'Calcium hydroxide (Ca(OH)2) formed as a dry powder when any lime is slaked using an exact amount of water (cf lime putty). Not to be confused with hydraulic lime. It is possible to obtain hydrated hydraulic lime or hydrated non-hydraulic lime.'
[edit] Related articles on Designing Buildings
Featured articles and news
Licensing construction in the UK
As the latest report and proposal to licence builders reaches Parliament.
Building Safety Alliance golden thread guidance
Extensive excel checklist of information with guidance document freely accessible.
Fair Payment Code and other payment initiatives
For fair and late payments, need to work together to add value.
Pre-planning delivery programmes and delay penalties
Proposed for housebuilders in government reform: Speeding Up Build Out.
High street health: converting a building for healthcare uses
The benefits of health centres acting as new anchor sites in the high street.
The Remarkable Pinwill Sisters: from ‘lady woodcarvers’ to professionals. Book review.
Skills gap and investment returns on apprenticeships
ECA welcomes new reports from JTL Training and The Electrotechnical Skills Partnership.
Committee report criticises UK retrofit schemes
CIOB responds to UK’s Energy Security and Net Zero Committee report.
Design and construction industry podcasts
Professional development, practice, the pandemic, platforms and podcasts. Have we missed anything?
C20 Society; Buildings at Risk List 2025
10 more buildings published with updates on the past decade of buildings featured.
Boiler Upgrade Scheme and certifications consultation
Summary of government consultation, closing 11 June 2025.
Deputy editor of AT, Tim Fraser, discusses the newly formed society with its current chair, Chris Halligan MCIAT.
Barratt Lo-E passivhaus standard homes planned enmasse
With an initial 728 Lo-E homes across two sites and many more planned for the future.
Government urged to uphold Warm Homes commitment
ECA and industry bodies write to Government concerning its 13.2 billion Warm Homes manifesto commitment.
From project managers to rising stars, sustainability pioneers and more.
Places of Worship in Britain and Ireland, 1929-1990. Book review.