DESIGN GUIDELINES

Masonry

Masonry repointing should be done with considerable care by a reputable mason with demonstrated experience with masonry restoration. Repointing is the partial removal of deteriorated or missing mortar from between masonry units and its replacement with new mortar.

For additional information see Preservation Brief 2 Repointing Mortar Joints in Historic Masonry, National Park Service, and US Department of the Interior: http://www.nps.gov/tps/how-to-preserve/briefs/2repoint-mortar-joints.htmd

Recommended

• Original brick, stone, terra cotta, cast concrete and other masonry original to the building should be preserved and maintained.

• Missing areas of masonry or areas of masonry seriously deteriorated to the extent the masonry unit no longer has integrity, should be reconstructed matching the historic masonry materials as close as possible including masonry unit size, type, coursing, color and strength. Replacement mortar should match the historic mortar in strength, color and composition and joint tooling. Masonry units should be toothed-in to the old masonry to disguise the joint between the old and the new.

• Masonry repointing should be done with considerable care and by a reputable mason with demonstrated experience with masonry restoration. Repointing mortar for historic buildings should typically be a soft, high lime content mortar. A mortar analysis is recommended to determine the components of the mortar and its strength.

• Masonry that has never been painted should remain unpainted unless the brick and mortar are extremely mismatched from repairs or patching.

• Historically painted masonry surfaces should be maintained and remain painted. When restoring, use only specialized coatings for masonry surfaces.