Saint-Astier® Natural Hydraulic Lime
Saint-Astier® Natural Hydraulic Lime (NHL) is an industry-standard used for historic restoration mortar, stucco, and Plaster with no harmful portland cement present or required. Saint-Astier® NHL is pure and natural, free of additives, and has been in use throughout the world for over 150 years. To learn more about Saint-Astier® visit StAstier.com.
Why SAINT-ASTIER® NHL?
Need Pre-mixed material?
Check out our premixed Ecologic Mortar, based on Saint Astier Natural Hydraulic Lime.
Need something more custom?
We do custom simulations for mortar, brick, stone, terracotta, and paint. Visit “Ordering a Custom Formulated Simulation” to learn more.
Maintaining good vapor permeability in the exterior envelope of an historic building will allow the historic masonry units themselves to have an even longer service life thus keeping them in a better state of conservation. Vapor permeability is also key to the longevity of new sustainable construction projects. Saint-Astier® NHL has low capillarity and high vapor permeability. Independent studies have shown Saint-Astier® NHL to have a higher level of vapor permeability than all mortar mixes containing any amount of Portland cement. This remains true while achieving comparable strengths for many applications without the need to add Portland cement or a Pozzolan to achieve proper and effective mix designs.
Immune to Salts and Sulfates
Saint-Astier® NHL is completely immune to sulfates and salts. Alkali-silica reactions, common with Portland cement mortars do not take place with Saint-Astier Natural Hydraulic Limes. This is due to the absence of tri-calcium aluminates only created in high temperature fired kilns which are required for the production of Portland Cement.
Modulus of Elasticity
Saint-Astier® NHL has an excellent modulus of elasticity. Unlike Portland cement-based mortars, Saint-Astier® NHL mortars limit the requirements for strategically placed control joints in walls. The breathability of mortars made with Saint-Astier® NHL also reduces, if not eliminating, the requirement for weep vents in curtain or veneer walls.
NHL 2 (Natural Hydraulic Lime)
- Feebly Hydraulic lime is used where the highest amount of “free lime” is desired along with the greatest modulus of elasticity, low strength or high vapor exchange. It sets with air and water and cures in about four days
- Very soft pointing mortars used for repairing around friable historic masonry
NHL 2 Bag Coverage for Plaster and Stucco
NHL 3.5 (Natural Hydraulic Lime)
- Moderately Hydraulic lime is recommended for use when moderate strengths and better freeze-thaw resistance is required.
- Used for applications such as laying or repointing brick, stone and terra cotta units even in extreme freeze-thaw climate cycles.
- It can be used to make scratch, brown and finish coats of exterior stucco
- Quick Estimation Numbers
NHL 3.5 Bag Coverage for Plaster and Stucco
NHL 5 (Natural Hydraulic Lime)
- Eminently Hydraulic lime is specified when strength and high freeze-thaw resistance are necessary.
- Used for applications such as building or repairing wall head copings, pointing and parging the water table or foundation of a building and making lime concrete. Sea-bearing walls can be built and repaired with NHL 5 since it has only trace amounts of soluble salts.
NHL 5 Bag Coverage for Plaster and Stucco
Application and Product Data
- Ecologic™ and Saint-Astier® Stucco and Plaster Comparison Chart
- The 5 Most Important Steps
- Los Cinco Pasos Más Importantes Para la
Preparación del Producto
- NHL Breathability
- Physical & Mechanical Data
- NHL Reworking
- Sea Water Resistance
- 24 Month Tests
Safety Data Sheets (SDS)
General Installation Guidelines
St. Astier Natural Hydraulic Lime for Historic Restoration, Conservation and New Build Projects
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What Sand Should I Use With Natural Hydraulic Lime For Repointing My Building? FAQ Friday
One quick question on Natural Hydraulic Lime, FAQ Friday
Differences Between Repointing with Natural Hydraulic Lime (NHL) Mortars vs. Cement-Based Mortars FAQ
With all of the info LimeWorks provides and the great products they sell, I was able to match our repairs perfectly to the 114 year old stucco on our house. Truly a great product and a great company! Picture is during the finish coat application so you can see what’s new and what’s existing. On this area and many others we used 12x 55lb bags of NHL 3.5 and a little over 1T of sand, the Lime was consistent throughout all of it.
I ordered a 55lb bag of NHL 5 to restore the parging of a wall in my 100-year-old basement (the mix was 2½:1 with all purpose sand from Home Depot). The bag was packaged with bubble wrap and placed in an appropriately sized cardboard box with all seams sealed with tape. Natural Hydraulic Lime is somewhat of a rare material in the US, so I was pleased that Limeworks offers fast shipping at a reasonable rate.
Great service, I will definitely be back!