The article describes a method of mortar consolidation using lime water. This traditional method has been used by restorers and craftsmen for centuries with good results. The method works by replacing the calcium in brittle or friable plaster or mortar, or in flaking or powdered paint layers with lime (the binding medium in mortar, plaster or pigments is regenerated). This consolidation does not involve the introduction of a compound with a different character into the original material. This means that the consolidated material retains its original properties and behavior. See also AATA 19-1792.