A. Section includes historic treatment work consisting of rep ointing brick masonry as follows:

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1 SECTION HISTORJC BRlCK UNIT MASONRY REPOINTING PART 1- GENERAL 1.1 RELATED DOCUMENTS A. Drawings and general provisions of the Contract, including General and Supplementary Conditions and Division 01 Specification Sections, apply to this Section. 1.2 SUMMARY A. Section includes historic treatment work consisting of rep ointing brick masonry as follows: 1. Repainting joints with mortar. 2. Wideningjoints. B. Related Requirements: 1. "Mortar Specification" for mortar mix requirements. 1.3 UNIT PRlCES A. Work of this Section is affected by unit prices specified in Section "Unit Prices." 1. Unit prices apply to authorized work covered by estimated quantities. 2. Unit prices apply to additions to and deletions from Work as authorized by Change Orders. 1.4 DEFINITIONS A. Low-Pressure Spray: 100 to 400 psi; 4 to 6 gpm. 1.5 PREINSTALLATION MEETINGS A. Preinstallation Conference: Conduct conference historic masonry repair and repainting at Project site. 1. Review minutes of Preliminary Historic Treatment Conference that pertain to masonry historic treatment and repainting. 2. Review methods and procedures related to repainting historic brick masonry, including, but not limited to, the following: a. Historic treatment specialist's personnel, equipment, and facilities needed to make progress and avoid delays. b. Materials, material application, sequencing, tolerances, and required clearances. HISTORJC BRlCK UNIT MASONRY REPOINTING

2 c. Quality-control program. d. Fire-protection plan. e. Unit masonry historic treatment program. f. Coordination with building occupants. 1.6 SEQUENCING AND SCHEDULING A. Order material for pointing mortar immediately after approval of Samples. Take delivery of and store at Project site a sufficient quantity to complete Project. - B. Work Sequence: Perform masonry historic treatment work in the following sequence, which includes work specified in this and other Sections: 1. Remove plant growth. 2. Inspect masonry for open mortar joints and repair before cleaning to prevent the intrusion of water and other cleaning materials into the wall. 3. Remove paint. 4. Clean masonry. 5. Rake out mortar from joints surrounding masonry to be replaced and from joints adjacent to masonry repairs along joints. 6. Repair masonry, including replacing existing masonry with new masonry materials. 7. Rake out mortar from joints to be repainted. 8. Point mortar and sealant joints. 9. After repairs and repainting have been completed and cured, perform a final cleaning to remove residues from this work. 10. Where water repellents are to be used on or near masonry work, delay application of these chemicals until after pointing and cleaning. C. As scaffolding is removed, patch anchor holes used to attach scaffolding. 1.7 ACTION SUBMITTALS A. Product Data: For each type of product. 1. Include construction details, material descriptions, dimensions of individual components and profiles, and finishes. 2. Include recommendations for product application and use. Include test data substantiating that products comply with requirements. B. Shop Drawings: 1. Include plans, elevations, sections, and locations of rep ointing work on the structure. 2. Show provisions for expansion joints or other sealant joints. 3. Show locations of scaffolding and points of scaffolding in contact with masonry. Include details of contact or anchorage. C. Samples for Initial Selection: For the following: 1. Sand Type Used for Pointing Mortar: Minimum 8 oz. of each in plastic screw-top jars. HISTORIC BRICK UNIT MASONRY REPOINTING

3 a. For blended sands, provide Samples of each component and blend. Identify blend ratio. b. Identify sources, both supplier and quarry, of each type of sand. 2. Sealant materials. 3. Include similar Samples of accessories involving color selection. D. Samples for Verification: For the following: 1. Sealant materials. 2. Accessories: Each type of anchor, accessory, and miscellaneous support. 1.8 Qualification Data: For field supervisors and workers. A. Quality-control program. B. Unit masonry historic treatment program. 1.9 QUALITY ASSURANCE A. Historic Treatment Qualifications: Experience in pointing or repainting only new or nonhistoric masonry is insufficient experience for masonry historic treatment work. B. Quality-Control Program: Prepare a written quality-control program for this Project to systematically demonstrate the ability of personnel to properly follow methods and use materials and tools without damaging masonry. Include provisions for supervising worker performance and preventing damage. C. Mockups: Prepare mockups of historic treatment on existing surfaces to demonstrate aesthetic effects and to set quality standards for materials and execution. 1. Widening Joints: Widen a joint in two separate locations, each approximately 12 inches long. 2. Repainting: Rake out joints in two separate areas, each approximately 36 inches high by 48 inches wide for each type of repainting required, and repaint one of the areas. 3. Approval of mockups does not constitute approval of deviations from the Contract Documents contained in mockups unless Architect specifically approves such deviations in writing. 4. Subject to compliance with requirements, approved mockups may become part of the completed Work if undisturbed at time of Substantial Completion DELIVERY, STORAGE, AND HANDLING A. Deliver packaged materials to Project site in manufacturer's original and unopened containers, labeled with manufacturer's name and type of products. B. Store cementitious materials on elevated platforms, under cover, and in a dry location. Do not use cementitious materials that have become damp. HISTORIC BRICK UNIT MASONRY REPOINTING

4 C. Store hydrated lime in manufacturer's original and unopened containers. Discard lime if containers have been damaged or have been opened for more than two days. D. Store sand where grading and other required characteristics can be maintained and contamination avoided FIELD CONDITIONS A. Weather Limitations: Proceed with installation only when existing and forecasted weather conditions permit repainting work to be performed according to product manufacturers' written instructions and specified requirements. B. Temperature Limits, General: Repaint mortar joints only when air temperature is between 40 and 90 deg F and is predicted to remain so for at least seven days after completion of the Work unless otherwise indicated. C. Cold-Weather Requirements: Comply with the following procedures for mortar-joint pointing unless otherwise indicated: 1. When air temperature is below 40 deg F, heat mortar ingredients and existing masonry walls to produce temperatures between 40 and 120 deg F. 2. When mean daily air temperature is below 40 deg F, provide enclosure and heat to maintain temperatures above 32 deg F within the enclosure for seven days after pointing. D. Hot-Weather Requirements: Protect mortar-joint pointing when temperature and humidity conditions produce excessive evaporation of water from mortar materials. Provide artificial shade and wind breaks, and use cooled materials as required to minimize evaporation. Do not apply mortar to substrates with temperatures of 90 deg F and above unless otherwise indicated. E. For manufactured repair materials, perform work within the environmental limits set by each manufacturer. PART 2- PRODUCTS 2.1 MATERIALS, GENERAL A. Source Limitations: Obtain each type of material for repainting historic masonry (cement, sand, etc.) from single source with resources to provide materials of consistent quality in appearance and physical properties. 2.2 MORTAR MATERIALS A. B. Testing and Analysis: Testing and analysis is the best way to determine original composition of mortar mix. Mortar Composition: Must match original mortar in color, texture, strength and hardness (density and porosity). HISTORIC BRICK UNIT MASONRY REPOINTING

5 C. Portland Cement: ASTM C 150, Type I. Provide natural color cement to produce required mortar color that will match original construction. This is typically gray but a white portland cement is also available. D. Portland Cement-Lime Mix: Packaged blend of Portland cement complying with ASTM C 150, Type I and hydrated lime complying with ASTM C 207. E. Mortar Cement: ASTM C DO NOT USE F. Masonry Cement: ASTM C 91 G. Hydrated Lime: ASTM C 207 Type S. H. Mortar Aggregates: ASTM C 144 Cement sand will allow for larger grain particles than masonry or play sand. I. Water: Potable MORTAR MIX A. General: Two (2) parts Cement, one (1) part Lime and nine(<>) parts Sand. This will give you a base for matching existing mortar joints. All components can be adjusted for a more exact match. Additional cement will make for a harder composition, but could prove to be harder than the stone or masonry units, thus compromising the integrity of building material. Additional lime will make for a softer joint that would take additional time to cure. It was not uncommon for very old historic structures to be constructed with only lime and sand mortars. These structures have proven to stand for hundreds of years. Choice of lime will also allow for variations in color. Changes in sand will give you a variety of color and texture. Other additions of crushed flint or marble can be substituted for sand to. change the mortar composition as well. B. Do not use admixtures, including pigments unless historically correct, air-entraining agents, accelerators, retarders, water-repellent agents, antifreeze compounds, or other admixtures. 1. Do not use calcium chloride. 2. Limit cementitious materials in mortar to portland cement, masonry cement and lime. 3. Mixing Pointing Mortar: Thoroughly mix Cementitious and aggregate materials together before adding water. Then mix again, adding only enough water to produce a damp, unworkable mix that will retain its form when pressed into a ball. Maintain mortar in this dampened condition for one to two hours. Add remaining water in small portions until mortar reaches desired consistency. Use mortar within 30 minutes.of final mixing; do not re-temper or use partially hardened material. PART 3- EXECUTION 3.1 PROTECTION A. Prevent mortar from staining face of surrounding masonry and other surfaces. 1. Cover sills, ledges, and other projecting items to protect them from mortar droppings. HISTORIC BRICK UNIT MASONRY REPOINTING

6 2. Keep wall area wet below rebuilding and pointing work to discourage mortar from adhering. 3. Immediately remove mortar splatters in contact with exposed masonry and other surfaces. B. Remove downspouts and associated hardware adjacent to immediate work area and store during masonry repainting work. Reinstall when repainting is complete. 1. Provide temporary rain drainage during work to direct water away from building. 3.2 MASONRY REPOINTING, GENERAL A. Appearance Standard: Repainted surfaces are to have a uniform appearance as viewed from 20 feet away by Architect. 3.3 WIDENING JOINTS A. Do not widen a joint, except where indicated or approved by Architect. B. Location Guideline: Where an existing masonry unit abuts another or the joint is less than 1/8 inch, widen the joint for length and depth required for repointing after obtaining Architect's approval. C. Carefully perform widening by using cutting, grinding, routing, or filing procedures demonstrated in an approved mockup. D. Widen joint to width equal to or less than predominant width of other joints on building. Make sides of widened joint uniform and parallel. Ensure that edges of units along widened joint are in alignment with joint edges at unaltered joints. 3.4 REPOINTING MASONRY A. Prepare stone-joint surfaces for pointing with mortar by removing dust and mortar particles. Clean out old joint to a depth of approximately 2 times the width of the joint. B. Moisten the joint NOT TOO WET. C. Point stone joints by placing and compacting pointing mortar in layers not more than 3/8 inch (1 0 mm) deep. Compact each layer thoroughly and allow to become thumbprint hard before applying next layer. It is especially important to apply repointing mortar in several layers if the mortar is a little too wert. D. Tool joint, when pointing mortar is thumbprint hard, with a smooth jointing tool or by pounding with a hard bristle brush to produce a joint profile that matches existing. HISTORIC BRICK UNIT MASONRY REPOINTING

7 3.5 A. B. c. D. FINAL CLEANING Immediately remove stains, efflorescence, or other excess resulting from the work of this section. Remove excess mortar, smears, and droppings as work proceeds and upon completion. Clean surrounding surfaces. Remove large mortar particles by hand with wooden paddles and nonmetallic scrape hoes or chisels. Clean stone masonry with proprietary non-acidic cleaner applied according to manufacturer's written instructi 3.6 A. B. FIELD QUALITY CONTROL Architect's Project Representatives: Architect will assign Project representatives to help carry out Architect's responsibilities at the site, including observing progress and quality of portion of the Work completed. Allow Architect's Project representatives use of lift devices and scaffolding, as needed, to observe progress and quality of portion of the Work completed. Notify Architect's Project representatives in advance of times when lift devices and scaffolding will be relocated. Do not relocate lift devices and scaffolding until Architect's Project representatives have had reasonable opportunity to make inspections and observations of work areas at lift device or scaffold location. END OF SECTION HISTORIC BRICK UNIT MASONRY REPOINTING

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