Roundtower - NHL 2
Roundtower Lime's NHL 2 is a feebly hydraulic Lime, suitable for internal and external use particularly where the masonry is a soft material.
Although NHL 3.5 seems to have become the go to, faster setting alternative to traditional lime putty mortars, NHL2 is arguably a better choice as a general purpose lime mortar, reserving NHL 3.5 for situations that need extra strength or protection. NHL2 is the closest in strength, flexibility and breathability to a traditional Hydrated lime putty mortar.
NHL (Natural Hydraulic Lime) is made from limestone which contains naturally occurring impurities. These impurities aid the setting time and hardness of the lime. Roundtower Lime contains no artificial additives included in the mix. Available in 25kg water resistant bags.
NHL 2 is ideal for:
- Rendering and Plastering internal and external walls.
- Building and pointing, particularly for softer masonry such as limestone and sandstone.
NHL will set in the presence of water which makes it ideal for use on exterior applications.
For applications that require extra strength or protection, you may want to consider NHL 3.5
For, limecrete floors, marine environments and areas of high exposure such as chimneys and Roof Ridge tiles we recommend NHL 5.
Always remember that the mortar should not be harder than the masonry.
Approximate coverage rates
Plastering & Rendering with a mix of 2.5 parts sand to 1 part lime at 10mm thickness covers approximately 8m².
Pointing Rubble Stone with a mix of 2.5 parts sand to 1 part lime covers approximately 10m².
Pointing Brickwork with a mix of 2.5 parts sand to 1 part lime covers approximately 16m².
|NHL type||Suggested mix ratio by volume|
|Pointing / building / plastering||NHL 2 / NHL 3.5||
2.5 Sharp sand :
|Laying Flag stones / Limecrete slabs||NHL 5||2.5 Sharp sand :
1 Hydraulic lime
Paving, copings, chimneys,
|NHL 5||2 Sharp sand :
1 Hydraulic lime
We have a great selection of articles about lime and it's use. Everything from hotlime to bag-rubbing. Take a look at our Lime Products guide for information and inspiration.