Lime: an introduction
Practical Action
ash), can also be mixed with lime to improve its strength and durability.
Architects are increasingly becoming aware of the problems of Portland cement mortars and
many now specify blended lime-Portland cement mortars. Recently, lime has played a leading
role, worldwide, in the conservation of old buildings, most of which were built in the 'pre-
Portland cement' era. It is well recognized that successful preservation of ancient
monuments, such as churches, castles and other historic sites, necessitates the application
of the same binding systems as were used originally. Attempts in the past at patching up
these buildings with ordinary Portland cement-based mixes have invariably led to even greater
problems of decay occurring at a later stage.
Lime also has considerable economic advantages over Portland cement. The latter is relatively
expensive to produce and critically for developing countries, often requires expensive
imported technologies and fuels. Lime has none of these disadvantages and is normally
considerably cheaper to produce, needs much lower or even negligible capital inputs to get
started, and requires far less imported technology and equipment. It can also be produced on
a small scale to supply a local market. This greatly reduces transportation costs and provides
a much greater degree of local accountability in the supply of building materials. Portland
cement on the other hand tends to be produced in large centralized plants which inevitably
leads to distribution difficulties and high transportation costs.
Lower production and transportation costs make for lower purchase costs to the consumer,
enabling those who could not afford Portland cement to purchase and use a quality binding
material on construction projects. The production and use of lime also has several social
advantages. Its production is normally labour intensive, unlike the capital-intensive methods
required for Portland cement, and provides opportunities for local employment. This can be
particularly important in urban areas in developing countries where unemployment rates are
frequently very high.
References and further reading
Lime - An Introduction Practical Action Technical Brief
Hydraulic Lime - An Introduction Practical Action Technical Brief
Methods for testing lime in the field Practical Action Technical Brief
How to calculate the Energy Efficiency of Lime Burning Practical Action Technical
Brief
Testing methods for pozzolanas Practical Action Technical Brief
Lime Kiln Designs: Small & Medium Scale Oil Fired Lime Kilns Practical Action
Technical Brief
A Small Lime Kiln for Batch and Continuous Firing Practical Action Technical Brief
The Small Scale Vertical Shaft Lime Kiln: A practical guide to design, construction
and operation, Kelvin Mason, Practical Action Publishing, ISBN 9781853394652
Small-scale Lime-burning: A practical introduction Michael Wingate, Practical Action
Publishing, ISBN 9780946688012
A Case Study in Lime Production No2 Improved Techniques at Chenkumbi, Malawi.
Practical Action Technical Brief
Lime and Alternative Binders in East Africa Elijah Agevi et al, Practical Action /ODA,
1995
Lime and Other Alternative Cements Neville Hill et al, Practical Action Publishing,
1992
Building with Lime: A practical introduction. Revised Edition Stafford Holmes &
Michael Wingate, Practical Action Publishing, 2002/3 ISBN 9781853395475
Guide for Manufacture of Lime in Vertical Mixed-feed type lime kiln: Part 1 From
lime-stone, Indian Standard IS 1861 Part 1 – 1990, Bureau of Indian Standards,
New Delhi, India
How to Build a Small Vertical Shaft Lime Kiln Practical Action Technical Brief
Pozzolanas - An Introduction Practical Action Technical Brief
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