Singleton Birch (Secil) Hydraulic Lime - NHL3.5

Hydraulic Lime is produced from limestone containing clay and other impurities which enables it to set without exposure to air (unlike fat lime products). It therefore means that these limes can be used in harsher conditions e.g. they are ideal for use in foundations, limecrete floors, sea-defence walls, chimneys, parapets, copings, paving etc. The products in this range are produced in Portugal by Secil who have been producing high quality limes for over 100 years. Natural Hydraulic Limes (NHLs) are categorised, where the number refers to the compressive strength of the mortar after 28 days (please note the selection of aggregate and mix ratio will also effect the final strength)

• NHL 2 is the slowest setting of all the hydraulic limes, but also the most flexible and vapour permeable and so is primarily used for internal work and external work in sheltered areas on strawbale, cob, soft masonry or brick.

• NHL3.5 gives a slightly faster set and can be used for external work in most areas with most masonry types.

• NHL5 has a much faster set and achieve s a greater strength, it is typically used for external works in exposed areas such as chimneys, copings or river and canal works, floors.

These limes have become increasing popular over the last decade because of their comparative ‘ease of use’ and ‘strength' compared with non-hydraulic fat-limes. However, they should be used for the right situation as limes that are too strong can cause damage to the fabric of the building in the same way that cement does. The golden rule is that the mortar or plaster should always be weaker than the building components it is used on.

Please call for advice or see Choosing a Lime in the Documentation below.

Hydraulic Limes are supplied as a powder to which water and sand must be added in the correct ratios 

We supply a wide range of aggregates suitable for use with these limes.

Please note that this product must be stored completely dry and frost-free and used straight away.

Bulk order discounts apply to this product, the more you add the more discount you will accumulate!

This product now holds a BBA Certificate - please see here! 

To see an example of this product in use, see our case study of Maesgwyn Cottage, Carmarthenshire, Pontithel House, Near Glasbury, Nash's House, Stratford Upon Avon and The Charterhouse, Coventry.