Where To Buy Hydraulic Lime [UPD]
Hydraulic limes (so called because they set under water) are made in the same way as non-hydraulic lime but using different limestone. They are sold as hydrated lime and have an initial set when water is added, followed by hardening while they absorb carbon dioxide. The more hydraulic a lime is the faster it sets and the higher it's final strength, but this means that it is less breathable and flexible. NHL5 is the most hydraulic, then NHL3.5, and NHL2 the least hydraulic lime. They do not perform in the same way as modern cements, nor contain the same damaging components. It should be noted however that limes marked with NHL-Z or just HL on the bag can contain some additions that could be potentially damaging and at worst be not much better than cement. Only use limes marked NHL - these meet the highest British and European standards.
where to buy hydraulic lime
Non-hydraulic lime (CL or DL 70-90) is sold as either hydrated lime or putty lime; they set and harden through drying out and absorbing carbon dioxide from the air. This means they have a very slow set: CO2 is only absorbed when certain conditions are met. They are the softest, most breathable limes available. These limes are also known as fat-lime, calcium-lime or air-lime.
Hydrated lime simply means that a controlled amount of water is added to quicklime to make a powder that is more stable and safe to handle. This can be done to hydraulic lime or non-hydraulic lime.
Lime putty can be made from either type of lime, and is made by adding an excess of water to quicklime. Hydraulic lime putty will set underwater within hours or days making them impractical, whereas non-hydraulic lime putty will remain plastic and improve with age.
Pozzolans are additions that may be added to achieve harder, faster sets to any sort of lime or cement. Pozzolans, when added, produce similar chemical reactions to those found in hydraulic limes, so they reduce breathability and flexibility in exactly the same way. The disadvantage is that you will never know how strong, breathable or flexible a pozzolan lime is beforehand, unless you have considerable experience or knowledge. Adding some types of pozzolans or even the smallest amounts of cement can be very damaging or produce poor performing lime mortars. We always recommend testing first.
Lime putty or hemp lime mixes should be used with caution in houses where damp is a problem. (N.B. if a wall is permanently very damp, a putty mix may never set.) Low suction backgrounds (hard stone or blue bricks etc) and damp cool weather also make the use of lime putty very slow, consider using Lime Green Duro or Ultra instead in these situations.
Lime putty is typically the first choice for internal plastering due to its plasticity and better vapour exchange: in thin layers it is easy for it to absorb CO2 and set. Limewash and lime paints are also typically made from non-hydraulic lime.
Using a lime that is too strong can be very damaging for some historic structures. People should be cautious with strong mixes: these are best kept for harsh conditions and high strength applications and avoided on friable, soft masonry or timber structures.
We only use good quality Natural Hydraulic Lime (NHL) or air lime from Buxton, which we know not to contain any sort of potentially damaging components. Lime from our suppliers quarries has been used on historic buildings since Roman times without problems. The chemical composition of Natural hydraulic limes makes the problems associated with cement impossible.
It has been shown that even small amounts of cement in traditional mortars leads to inferior less durable mortars that can cause problems. If a mortar with a set is required then a hydraulic lime is more suitable. Building with cement and pointing with lime is also a waste of time technically and has no real advantages over a hydraulic lime mortar, which will allow building and pointing to be done in one operation.
There are three Hydraulic Lime Mortar options; NHL 2, NHL 3.5 and NHL 5. The number relates to its compressive strength in N/mm (Newtons per square millimetre).
(b) the right to download, store or print single copies of individual Documents, or portions of such Documents, solely for Licensee's own use. That is, Licensee may access and download an electronic file of a Document (or portion of a Document) for temporary storage on one computer for purposes of viewing, and/or printing one copy of a Document for individual use. Neither the electronic file nor the single hard copy print may be reproduced in anyway. In addition, the electronic file may not be distributed elsewhere over computer networks or otherwise. That is, the electronic file cannot be emailed, downloaded to disk, copied to another hard drive or otherwise shared. The single hard copy print may only be distributed to others for their internal use within your organization; it may not be copied. The individual Document downloaded may not otherwise be sold or resold, rented, leased, lent or sub-licensed.
(iii) Specifically, no one is authorized to transmit, copy, or distribute any Document in any manner or for any purpose except as described in Section 3 of this License, without ASTM's prior express written permission. In particular, except as described in Section 3, no one may, without the prior express written permission of ASTM: (a) distribute or forward a copy (electronic or otherwise) of any article, file, or material obtained from any ASTM Product or Document; (b) reproduce or photocopy any standard, article, file, or material from any ASTM Product; (c) alter, modify, adapt, or translate any standard, article, file, or material obtained from any ASTM Product; (d) include any standard, article, file, or material obtained from any ASTM Product or Document in other works or otherwise create any derivative work based on any materials obtained from any ASTM Product or Document; (e) impose any charge for a copy (electronic or otherwise) of any standard,article, file, or material obtained from any ASTM Product or Document, except for normal printing/copying costs where such reproduction is authorized under Section 3; or (f) systematically download, archive, or centrally store substantial portions of standards, articles, files, or material obtained from any ASTM Product or Document. Inclusion of print or electronic copies in coursepacks or electronic reserves, or for distance learning use, is not authorized by this License and is prohibited without ASTM's prior written permission.
Essentially, as its name suggests, Natural Hydraulic Lime (NHL) is a naturally occurring lime material generally associated with building conservation or as a green, eco-building material. Its use dates back to the times of the ancient Egyptians, Greeks and Romans but declined during the 19th century with the emergence of Ordinary Portland Cement (OPC).
The introduction of substitute "pozzolanic" materials such as fly ash to non-hydraulic lime in order to promote hydraulicity has produced varied results. It has therefore become common practice to add cement to Non-Hydraulic Lime mixes to ensure an early set. Whilst this may be suitable for use with current-day hard-fired bricks, the addition of cement to lime mortars makes them much harder and impervious to moisture transfer. The resultant entrapment of water within the softer material of older bricks and stone masonry units such as limestone or sandstone then promotes their eventual decay by de-crystalisation.
High calcium hydrated lime Ca(OH)2 is a dry powder produced by combining quicklime with a sufficient amount of water to satisfy the quicklime's natural affinity for moisture. The process converts CaO to Ca(OH)2. The amount of water required depends on both the particular characteristics of the quicklime and the type of hydrating equipment available. Hydrated lime easily forms as a suspension or slurry and is often pumped to multiple process locations within industrial plants. The resulting solution is strongly alkaline, having a pH of 12.4. Most hydrated limes contain approximately 75% CaO and 25% H2O.
Hydrated lime is used in a variety of industrial applications including water treatment, as an anti-stripping agent in asphalt, and in soil stabilization. Some hydrated limes are sold into the food grade market as well. The product is commonly sold in 50 lb. bags or as a bulk material shipped in pneumatic truck trailers or rail tanker cars.
There are three distinct types of limestone, defined by their magnesium carbonate (MgCO3) concentrations. These types are Dolomitic (35 to 46% MgCO3), Magnesian (5 to 35% MgCO3) and High calcium (less than 5% MgCO3).
The Adams 6 Ton High Rise HLS-6-2W is a top of the line hydraulic lime spreader. Designed with one 12K axle and a 50 ft. spread pattern. This unique design is perfect for any of your fertilizer and/or lime application needs. Hydraulic engaging m...
The Adams 6 Ton HLS-6-4W is a top of the line hydraulic lime spreader. Designed with two 12K axle and a 50 ft. spread pattern. This unique design is perfect for any of your fertilizer and/or lime application needs. Hydraulic engaging and twin 24...
The Adams 6 Ton High Rise HLS Wide Row is a top of the line hydraulic lime spreader. Designed with one 12K axle and a 50 ft. spread pattern. This unique design is perfect for any of your fertilizer and/or lime application needs. Hydraulic engagi...
The Adams 8 Ton HLS-8-2W is a top of the line hydraulic lime spreader. Designed with one 12K axle and a 50 ft. spread pattern. This unique design is perfect for any of your fertilizer and/or lime application needs. Hydraulic engaging and twin 24...
The Adams 8 Ton HLS-8-4W is a top of the line hydraulic lime spreader. Designed with two 12K axle and a 50 ft. spread pattern. This unique design is perfect for any of your fertilizer and/or lime application needs. Hydraulic engaging and twin 24... 041b061a72