Evidence of the use of lime in construction dates back to 4000 BC and the construction of the Egyptian Pyramids.
Historically, lime was used in a variety of ways in construction, including whitewash, mortars, plasters, and stucco/renders. Lime for these applications was produced by burning limestone in small, hillside kilns near the jobsite. Quicklime produced by these kilns was placed into pits where water was added. Slaked quicklime was soaked for long periods of time to ensure suitable working characteristics for the mortar.
Today, lime-based mixes are the logical choice for restoring historic buildings for several reasons:
- High-lime-content mortars and plasters are compatible with historic materials. For example, buildings over 100 years old may have been constructed by hand-pressed brick that have low compressive strength. If walls containing these materials are pointed with a mortar with high cement content, the masonry units can be damaged when the building expands and contracts.
- Mortars, plasters and stuccos having high levels of lime are vapor-permeable. This reduces the potential for damage from water buildup in the wall.
- Use of lime-based products can replicate original building practices.
Graymont produces several different types of hydrated lime products suitable for restoration projects including the following:
Niagara® Mature Putty is a high-purity dolomitic lime putty, fully slaked and screened for immediate use. The putty is made from the purest dolomitic limestone available. The stone deposit was discovered in 1890 in northwest Ohio, USA, and is said to be the purest in the world. Niagara® is cured for a minimum of two months to develop excellent working characteristics.
Niagara ® Mature Lime Putty complies with ASTM C1489 (Standard specification for lime putty for structural purposes). The product is available in 45-gallon drums or three-gallon pails.
Type N Hydrate Lime
GRAND PRIZE® Type N Finishing Lime is a single-hydrated (Type N) product made from high-purity dolomitic limestone. Type N hydrated limes were popular in the first half of the 20th century. Similar to historic lime applications when lime was soaked for long periods of time before use, this product requires a minimum of 16 hours soaking to develop sufficient hydration. Grand Prize complies with ASTM C206 and ASTM C207 Type N requirements. Available in 50-lb. (22.5-kg) bags.
Type S Hydrated Lime
IVORY® Type S Finish Lime is made from high-purity dolomitic limestone, autoclaved for immediate use with gauging plasters without soaking or slaking. IVORY® Finish Lime is especially formulated to be compatible with standard gauging plasters. Use IVORY® Finish Lime with high-strength gauge, Keenes Cement, and all other manufacturer's gauging plasters for high plasticity, tight bonding and the smooth troweling sought by plasterers. IVORY® Finish Lime permits a thin finish coat, while the gauging plaster provides initial set and early hardness to minimize shrinkage of lime, for either smooth-trowel or textured sand-float interior finishes. Walls become exceptionally hard and crack-resistant while maintaining their long-lasting beauty. This product complies with ASTM C206 Type S and Federal Specification SS-L-351 B Type F. It also complies with ASTM C207 Type S requirements. Available in 50-lb. (22.5-kg) bags.
Graymont's Genoa, OH and Eden, WI facilities manufacture Type S Mason's lime products under three brand names, Mortaseal®, Miracle® and Super Limoid S®. These products are fully hydrated and are available for immediate use. When properly combined with cement and sand, they create a lime mortar having superior performance and ageless durability. Due to the low air content of these products, Mortaseal® and Super Limoid S® provide exceptional bond strength in mortars. Both Mortaseal® and Super Limoid S® comply with ASTM C207 (Hydrated Lime for Masonry Purposes) specifications. These products are available in durable three-ply, weather-resistant poly-lined 50-lb. (22.5-kg) bags, 2000 lb supersacks or for delivery in pneumatic bulk tankers.
Type SA Hydrated Lime
Graymont's Genoa, OH and Eden, WI facilities manufacture Type SA Mason's lime products under the following brand names Bondcrete®, Miracle SA® and Super Limoid SA®. These products are fully hydrated and available for immediate use. Type SA Mason's lime products contain an air entrainment additive that enhances workability and water retention of lime mortars. For stucco applications, air entrainment improves the sand carrying capacity (yield), workability and pumpability of the mix. Both Bondcrete® and Super Limoid SA® comply with ASTM C207 (Hydrated Lime for Masonry Purposes) specifications, Type SA. Both products are available in durable three-ply, weather-resistant and poly-lined 50-lb. (22.5-kg) bags or for delivery in pneumatic bulk tankers.
Graymont manufactures two blended hydraulic lime products, NIAGARA PHL 3.5 and 5.0. These products have been designed for use in restoration applications and meet the requirements of ASTM C1707 (Standard specification for pozzolanic hydraulic lime for structural purposes). They can be used in repointing, plastering, and grouting applications on historic or contemporary projects. These products are perfect for restoration applications where ordinary portland cements or masonry cements are not compatible with the existing masonry system. PHL 3.5 and 5.0 are available in 50-lb. (22.5-kg) bags.