Specifications include, but are not limited to: Repointing Specification of Buttresses and Retaining Walls: 1. Remove the two 42” diameter fiberglass planters. (CITY TASK) 2. Brush on a masonry cleaner called “30 Seconds Outdoor Cleaner” on all sides of the buttresses and retaining wall. Let it sit about 15 minutes and then pressure wash the entire structure with a low velocity pressure washer. The wall is very dirty and it may take more than one application. 3. Remove the new light grey mortar and pink mortar in all areas using a hammer and chisel near the stones. Do not use power tools for this application near the stones as doing so will likely result in damage to the red stones. Do not remove the original dark grey mortar; this is most prevalent by its course sandy texture and its recess about a ½” deep between the stones. Most of the original joints are thin. 4. Carefully analyze the original mortar, which is dark grey with a sandy texture. The color of the mortar should be obtained by using the correct color of natural sand with rounded edges. This is what was used in the 19th century and should still be available as it was always locally sourced. 5. Mix the sand with a cement/lime binder to obtain a generally weak mortar. Use a ratio of 1:3 (one part cement/lime to three parts natural dark grey sand). Do not use pre colored one-part mortars, as the texture will not be correct. There is loose sand at some joints on the west side of the buttresses that can be used for matching. 6. Repoint all joints where there is missing mortar now or where the lights grey and pink mortar were removed in step three above. Add new red stones where missing in about 4 locations. 7. Set the mortar deep into the space between the stones so that total width of the joint is generally not more than ½” to ¾” thick. Shape the mortar joint so that it is a “weathered joint” meaning that the bottom part will of the mortar joint be more forward than the top part so water will drain to the exterior of the wall or buttress instead of inside it. Do not use modern concave joints.
