The purpose of this guide is to assist those who wish to restore facades constructed of or finished with dimension stone. It is an aid to owners, building managers, architects, engineers, contractors and others involved with restoring dimension stone.

This guide is not meant to supersede manufacturers' directions and recommendations for the use of their specific products, or written directions from the architect or building owner. When manufacturers' directions are in conflict with this guide, follow their recommendations or consult with their technical staff for further direction.

Prior to undertaking a full-scale repair or cleaning procedure, the methods under consideration for repair, patching or cleaning should be tested on an area not easily visible or on sample stones. The test will assist in judging the effectiveness of the chosen method and permit assessment of potential damage to the building stone. Completely evaluate the success of the sample repairs before undertaking the full-scale cleaning or repair procedure.

1.1 This guide describes materials and procedures for restoring facades constructed of or finished with dimension stone. All of the materials, procedures, and principles are suitable for restoration of historic and nonhistosric structures.

1.2 This guide is not intended to address restoration of interior dimension stone, although many of the materials and procedures may be suitable for interior use.

1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory requirements prior to use.