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8/06/2020 <br /> <br />04 01 20 MASONRY REPAIR Page 7 of 9 <br />1. Remove mortar, loose particles, and soil from salvaged brick by cleaning with hand <br />chisels, brushes, and water. <br />2. Remove sealants by cutting close to brick with utility knife and cleaning with solvents. <br />3. Store brick for reuse. Store off ground, on skids, and protected from weather. <br />4. Deliver cleaned brick not required for reuse to Owner unless otherwise indicated. <br />F. Clean masonry surrounding removal areas to remove mortar, dust, and loose particles in <br />preparation for brick replacement/rework. <br />G. Replace removed damaged brick with new brick matching existing brick. Do not use broken <br />units unless they can be cut to usable size. <br />H. Install replacement brick in the same bonding and coursing orientation/pattern of the existing <br />brick. If cutting is required, use a motor-driven saw designed to cut masonry with clean, sharp, <br />unchipped edges. <br />1. Maintain joint width for replacement units to match existing joints. <br />2. Use setting buttons or shims to set units accurately spaced with uniform joints. <br />I. Lay replacement brick with new rebuilding (setting) mortar and with completely filled bed, <br />head, and collar joints. Butter ends with enough mortar to fill head joints and shove into place. <br />Wet both replacement and surrounding bricks that have ASTM C 67 initial rates of absorption <br />(suction) of more than 30 g/30 sq. in. per min. Use wetting methods that ensure that units are <br />nearly saturated but surface is dry when laid. <br />1. Tool exposed mortar joints in repaired areas to match joints of surrounding existing <br />brickwork. <br />2. When replaced brick is located within areas to be repointed, rake out mortar used for <br />laying brick before mortar sets according to the requirements for repointing in this <br />specification section. Point the mortar joints of the replaced brick at same time as the <br />surrounding brick joints are repointed. <br />3. When mortar is hard enough to support units, remove shims and other devices interfering <br />with pointing of joints. <br />J. Mortar used must be thoroughly mixed in quantities needed to conform with required <br />proportions and for immediate use, using only mixing methods specific to the type of mortar to <br />be used. Use mortar within 1-1/2 hours of mixing, after which unused mortar shall be discarded <br />unless otherwise confirmed through the manufacturer’s product data. This period shall be <br />reduced to 30 minutes in hot weather. Re-tempering shall be allowed in accordance with ASTM <br />C270, Subparagraph 6.4, only if it is demonstrated that re-tempering does not negatively affect <br />color consistency or final performance. Re-tempering shall be used to replace water lost to <br />evaporation only. Do not re-temper mortars which have begun to set. <br />K. Curing: Cure mortar by maintaining in thoroughly damp condition for at least 72 consecutive <br />hours, including weekends and holidays. <br />1. Hairline cracking within the mortar or mortar separation at edge of a joint is <br />unacceptable. Completely remove such mortar and repoint. <br />DocuSign Envelope ID: 7D9ACD4F-8F6C-42B6-9ADB-C60032DB6D03