040120 - Masonry Resto, Cleaning
MASONRY RESTORATION AND CLEANING
SECTION 04.01.20
PART 1 - GENERAL
1.1 GENERAL PROVISIONS
A. Attention is directed to the CONTRACT AND GENERAL CONDITIONS and all Sections
within DIVISION 01 - GENERAL REQUIREMENTS which are hereby made a part of
this Section of the Specifications.
1.2 DESCRIPTION OF WORK
A. Work Included: Provide labor, materials and equipment necessary to complete the work
of this Section, including but not limited to the following:
1. Power washing all masonry surfaces.
2. Repointing mortar joints, removing existing mortar and replacing with new matching
strength mortar. Testing of existing mortar for mix and strength composition shall be
performed by the mason prior to the beginning of any work.
3. Repointing shall consists at ground level through roof level. Provide staging or lift as
required to perform the work.
4. Cleaning exposed clay (brick) masonry surfaces, and preparing (wire/fiber brush)
clay (brick) masonry surfaces, removing plant growth (vines), applying cleaning
agent and chemical control (non-selective, post-emergence herbicide ie: glyphosate,
Monsanto’s “Round-Up Pro” or glufosinate ammonium, AgrEvo’s “Finale”) to retard
organic rooting, then thoroughly rinsing with clean water. --ensure all technicians
and inspectors are equipped with and observe the appropriate safety requirements
for wearing personal protection equipment (PPE) at all times, consistent with
cleaning and herbicide product manufacturer’s recommendations.
B. Alternates: Not Applicable.
C. Items To Be Installed Only: Not Applicable.
D. Items To Be Furnished Only: Not Applicable.
E. Related Work: The following items are included in this Section and will be performed
as appropriate, in accordance with the designated Sections:
1. Section 012200 – UNIT PRICES .for unit pricing per specified masonry restoration
repairs.
2. Section 079200 - JOINT SEALANTS for sealing joints in restored clay masonry.
1.3 DEFINITIONS
A. Low-Pressure Spray: 100 to 400 psi; 4 to 6 gpm.
B. Medium-Pressure Spray: 400 to 800 psi; 4 to 6 gpm.
C. High-Pressure Spray: 800 to 1200 psi; 4 to 6 gpm.
1.4 SUBMITTALS
A. Product Data: For each type of product indicated. Include recommendations for
application and use. Include test data substantiating that products comply with
requirements.
B. Samples for Verification: Before erecting mockup, submit samples of the following:
1. Each type of exposed masonry unit to be used for replacing existing units.
a. For each brick type, provide straps or panels containing at least four bricks.
2. Each type of sand used for pointing mortar.
a. For blended sands, provide samples of each component and blend.
b. Identify sources, both supplier and quarry, of each type of sand.
3. Each type of pointing mortar in the form of sample mortar strips, 6 inches long by ½
inch wide, set in aluminum or plastic channels.
a. Include with each sample a list of ingredients with proportions of each. Identify
sources, both supplier and quarry, of each type of sand and brand names of
cementitious materials and pigments if any.
4. Each type of masonry patching compound in the form of briquettes, at least 3 inches
long by 1-1/2 inches wide. Document each sample with manufacturer and stock
number or other information necessary to order additional material.
C. Qualification Data: For restoration specialists including field supervisors and chemical
manufacturer.
D. Restoration Program: For each phase of restoration process, provide detailed
description of materials, methods, equipment, and sequence of operations to be used
for each phase of restoration work including protection of surrounding materials on
building and Project site.
1. Include methods for keeping pointing mortar damp during curing period.
2. If materials and methods other than those indicated are proposed for any phase of
restoration work, provide a written description, including evidence of successful use
on comparable projects, and a testing program to demonstrate their effectiveness
for this Project.
E. Cleaning Program: Describe cleaning process in detail, including materials, methods,
and equipment to be used and protection of surrounding materials on building and
Project site, and control of runoff during operations.
1. If materials and methods other than those indicated are proposed for cleaning work,
provide a written description, including evidence of successful use on comparable
projects, and a testing program to demonstrate their effectiveness for this Project.
1.5 QUALITY ASSURANCE
A. Restoration Specialist Qualifications: Engage an experienced, masonry restoration and
cleaning firm to perform work of this Section. Firm shall have completed work similar in
material, design, and extent to that indicated for this Project with a record of successful
in-service performance.
1. At Contractor's option, work may be divided between two specialist firms: one for
cleaning work and one for repair work.
2. Field Supervision: Restoration specialist firms shall maintain experienced full-time
supervisors on Project site during times that clay masonry restoration and cleaning
are in progress. Supervisors shall not be changed during Project except for causes
beyond the control of restoration specialist firm.
3. Restoration Worker Qualifications: Persons who are experienced and specialize in
restoration work of types they will be performing.
B. Chemical Manufacturer Qualifications: A firm regularly engaged in producing masonry
cleaners that have been used for similar applications with successful results, and with
factory-trained representatives who are available for consultation and Project-site
inspection and assistance at no additional cost.
C. Source Limitations: Obtain each type of material for masonry restoration (face brick,
cement, sand, etc.) from one source with resources to provide materials of consistent
quality in appearance and physical properties.
D. Preconstruction Testing Service: Contractor shall engage a qualified independent
testing agency to test the following Provide test specimens and assemblies as
indicated.
1. Replacement Brick: For each proposed type of replacement brick, according to
sampling and testing methods in ASTM C 67 for compressive strength, 24-hour
cold-water absorption, 5-hour boil absorption, saturation coefficient, and initial rate
of absorption (suction). Whenever possible reuse existing masonry units. For new
units the Mason shall provide brick samples with best visual matching color, size
and texture. Refer to section below mockup requirements.
2. Existing Brick: For each type of existing brick indicated for replacement, according
to testing methods in ASTM C 67 for compressive strength, 24-hour cold-water
absorption, 5-hour boil absorption, saturation coefficient, and initial rate of
absorption (suction). Carefully remove existing bricks from locations designated by
Owner’s designer.
3. Analysis of existing mortar for strength. DO NOT INSTALL REPLACEMENT
MORTAR until the existing mortar has been tested.. Analysis of new mortar for
matching conformance to existing mortar strength.
4. Provide color samples for each replacement mortar for best visual match. Refer to
the section below for additional mockup requirements.
.
E. Mockups: Prepare mockups of restoration and cleaning as follows to demonstrate
aesthetic effects and qualities of materials and execution. Prepare mockups on existing
walls under same weather conditions to be expected during remainder of the Work.
1. For new masonry units, provide a 24” x 24” independent sample(s) with matching
masonry units and mortar. Architect and the LHA shall review mockup panels prior
to the installation of any new masonry units. DO NOT INSTALL REPLACEMENT
BRICKS WITHOUT AN APPROVED MOCK-UP PANEL BY THE LHA AND
ARCHITECT.
2. Repair an area approximately 36 inches high by 48 inches wide for each type of
masonry material indicated to be rebuilt or replaced.
3. Patch three small areas at least 1 inch in diameter for each type of masonry material
indicated to be patched.
4. Clean an area approximately 25 sq. ft. in area for each type of clay masonry and
surface condition.
a. Test cleaners and methods on samples of adjacent materials for possible
adverse reactions unless cleaners and methods are known to have deleterious
effect.
b. Allow a waiting period of not less than seven days after completion of sample
cleaning to permit a study of sample panels for negative reactions.
5. Rake out joints in two separate areas approximately 36 inches high by 72 inches
wide for each type of repointing required and repoint one of the two areas.
6. Comply with requirements of Section 013300 - SUBMITTAL REQUIREMENTS.
F. Preinstallation Conference: Conduct conference at Project site to comply with
requirements in Division 01.
1.6 DELIVERY, STORAGE, AND HANDLING
A. Deliver masonry units to Project site strapped together in suitable packs or pallets or in
heavy-duty cartons.
B. Deliver other materials to Project site in manufacturer's original and unopened
containers, labeled with manufacturer's name and type of products.
C. Store cementitious materials on elevated platforms, under cover, and in a dry location.
Do not use cementitious materials that have become damp.
D. 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.
E. Store lime putty covered with water in sealed containers.
F. Store sand where grading and other required characteristics can be maintained and
contamination avoided.
1.7 PROJECT CONDITIONS
A. Repoint mortar joints and repair masonry only when air temperature is between and 40
and 90 deg F and is predicted to remain so for at least 7 days after completion of work.
B. Cold-Weather Requirements: Comply with the following procedures for masonry repair
and mortar-joint pointing:
1. When air temperature is below 40 deg F, heat mortar ingredients, masonry repair
materials, 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 7 days after repair
and pointing. The Contractor shall be responsible for such enclosure work and
temporary heat with no additional cost to the Salem Housing Authority.
3. Do not use frozen materials or materials mixed or coated with ice or frost. Do not
build on frozen substrates. Remove and replace unit masonry damaged by frost or
by freezing conditions.
4. Cold-Weather Cleaning: Use liquid cleaning methods only when air temperature is
40 deg F (4 deg C) and above and will remain so until masonry has dried, but not
less than 7 days after completing cleaning.
C. Hot-Weather Requirements: Protect masonry repair and mortar-joint pointing when
temperature and humidity conditions produce excessive evaporation of water from
mortar and repair materials. Provide artificial shade and wind breaks and use cooled
materials as required. Do not apply mortar to substrates with temperatures of 90 deg F
and above.
D. Patch masonry only when air and surface temperatures are between and 55 and 100
deg F and are predicted to remain above 55 deg F for at least 7 days after completion
of work. On days when air temperature is predicted to go above 90 deg F, schedule
patching work to coincide with time that surface being patched will be in shade or during
cooler morning hours.
E. Clean masonry surfaces only when air temperature is 40 deg F and above and is
predicted to remain so for at least 7 days after completion of cleaning.
1.8 SEQUENCING AND SCHEDULING
A. Order replacement materials at earliest possible date, to avoid delaying completion of
the Work.
B. Order sand for repointing mortar immediately after approval of [Samples] [mockups].
Take delivery of and store at Project site a sufficient quantity of sand to complete
Project.
C. Perform masonry restoration work in the following sequence:
1. Remove plant growth.
2. Repair existing masonry, including replacing existing masonry with new masonry
materials.
3. Rake out joints that are to be repointed.
4. Point mortar joints.
5. Inspect for open mortar joints and repair before cleaning to prevent the intrusion of
water and other cleaning materials into the wall.
6. Remove paint.
7. Clean masonry surfaces.
8. Rake out joints that are to be repointed.
9. Point mortar joints.
D. As scaffolding is removed, patch anchor holes used to attach scaffolding. Patch holes in
masonry units to comply with Part 3 "Masonry Unit Patching" Article. Patch holes in
mortar joints to comply with Part 3 "Repointing Masonry" Article.
PART 2 - PRODUCTS
2.1 MASONRY MATERIALS
A. Face Brick and Accessories: Provide face brick and accessories, including specially
molded, ground, cut, or sawed shapes where required to complete masonry restoration
work.
1. Provide units with colors, surface texture, size, and shape to match existing
brickwork and with physical properties not less than those determined from
preconstruction testing of selected existing units.
a. Replacement brick at existing building: provide brick to match existing as
approved by Owner’s designer.
b. For existing brickwork that exhibits a range of colors, provide brick that matches
that range rather than brick that matches an individual color within that range.
c. Matching bricks for the purpose of this specification shall include but not
necessarily be limited to the following”
1. 3 Broad Street – BrickCraft – Traditional Red- Sold through Consolidate Brick
& Building Supply Services or approved equal.
2 117 Congress Street: Redland Brick KF University Blend Red through
Consolidate Brick & Building Supply Services or approved equal.
2. Provide units matching existing units in size and shape, with colors, surface texture,
and physical properties to match Owner’s designer’s sample.
a. For sample that exhibits a range of colors, provide brick that matches that range
rather than brick that matches an individual color within that range.
5. Provide specially molded shapes for applications where shapes produced by sawing
would result in sawed surfaces being exposed to view.
6. Provide specially ground units, shaped to match patterns, for arches and where
indicated.
B. Building Brick: Provide building brick complying with ASTM C 62, of same vertical
dimension as face brick, for masonry work concealed from view.
C. Existing Masonry Mortar: GC submit ASTM C-457 Analysis of Existing Mortar Sample
report. Match existing mortar characteristics for all work at existing masonry.
1. Color: Provide natural sand [or ground marble, granite, or other sound stone]; of
color necessary to produce mortar to best visual match of existing.
2. For pointing mortar, provide sand with rounded edges.
3. Match size, texture, and gradation of existing mortar sand as closely as possible.
Blend several sands, if necessary, to achieve suitable match.
D. Mortar Pigments: Natural and synthetic iron oxides, compounded for mortar mixes. Use
only pigments with a record of satisfactory performance in masonry mortars.
E. Water: Potable.
2.2 STONE REPAIR MATERIALS
A. Epoxy- Based Stone Repair Adhesive: A commercially available, two component,
moisture insensitive, high modulus, low viscosity, epoxy resin-formulated for penetrating
deep into masonry cracks. Acceptable Manufacturers: For the purpose of this
specification and to establish referenced standard, the Contractor shall install the
following stone repair material: Edison Coatings Custom System 45 Composite Repair
Compound for Stone, Masonry or Concrete. Acceptable other manufacturers shall
included: Bostone, Last Patch Limestone, Akepox 1005 or 1006 (Akemina). “Eucopoxy
Injection Resin” (Euclid Chemical Company), or approved equal. Color and texture of
epoxy repairs shall best visually match existing brownstone.
2.3 PAINT REMOVERS
A. Alkaline Paste Paint Remover: Manufacturer's standard alkaline paste formulation for
removing paint coatings from masonry.
1. Available Products:
a. American Building Restoration Products, Inc.; 800 Brush Grade.
b. Diedrich Technologies Inc.; 606/606X Extra Thick Multi-Layer Paint Remover.
c. Hydrochemical Techniques, Inc.; Hydroclean Heavy Duty Paint Remover (HT-
716).
d. Price Research, Ltd.; Price Heavy Duty Paint Stripper.
e. ProSoCo; Sure Klean Heavy-Duty Paint Stripper.
B. Covered or Skin-Forming Alkaline Paint Remover: Manufacturer's standard covered or
skin-forming alkaline formulation for removing paint coatings from masonry.
1. Available Products:
a. American Building Restoration Products, Inc.; Grip 'N Strip 800 F.A.
b. Diedrich Technologies Inc.; 404 Rip-Strip.
c. Dumond Chemicals, Inc.; Peel Away 1 System.
d. ProSoCo; Enviro Strip #2.
C. Solvent-Type Paint Remover: Manufacturer's standard water-rinseable, solvent-type gel
formulation for removing paint coatings from masonry.
1. Available Products:
a. American Building Restoration Products, Inc.; No. 3 Grip 'N Strip.
b. Diedrich Technologies Inc.; 505 Special Coatings Stripper.
c. Dominion Restoration, Inc.; Dominion Multi-Layer Paint & Graffiti Remover.
d. Dumond Chemicals, Inc.; Peel Away 2.
e. Hydrochemical Techniques, Inc.; Hydroclean Solvent Paint Remover (HT-300).
f. Price Research, Ltd.; Price Strip-All.
g. ProSoCo; Sure Klean Fast Acting Paint Stripper.
D. Low-Odor, Solvent-Type Paint Remover: Manufacturer's standard low-odor, water-
soluble solvent-type gel formulation, containing no methanol or methylene chloride, for
removing paint coatings from masonry.
1. Available Products:
a. American Building Restoration Products, Inc.; 800 No Lye Grip 'N Strip.
b. Dumond Chemicals, Inc.; Peel Away 6.
c. ProSoCo; Enviro Klean NMC.
2.4 CLEANING MATERIALS
A. Water for Cleaning: Potable.
B. Hot Water: Heat water to a temperature of 140 to 160 deg F.
C. Job-Mixed Detergent Solution: Solution prepared by mixing 2 cups of tetrasodium
polyphosphate (TSPP), 1/2 cup of laundry detergent, and 20 quarts of hot water for
every 5 gal. of solution required.
D. Job-Mixed Mold, Mildew, and Algae Remover: Solution prepared by mixing 2 cups of
tetrasodium polyphosphate (TSPP), 5 quarts of 5 percent sodium hypochlorite (bleach),
and 15 quarts of hot water for every 5 gal. of solution required.
E. Nonacidic Gel Cleaner: Manufacturer's standard gel formulation, with pH between 6 and
9, that contains detergents and chelating agents and is specifically formulated for
cleaning masonry surfaces.
1. Available Products:
a. Price Research, Ltd.; Price Marble Cleaner-Gel.
b. ProSoCo; Sure Klean 942 Masonry Cleaner.
F. Nonacidic Liquid Cleaner: Manufacturer's standard mildly alkaline liquid cleaner
formulated for removing mold, mildew, and other organic soiling from ordinary building
materials, including polished stone, brick, aluminum, plastics, and wood.
1. Available Products:
a. Dominion Restoration, Inc.; Bio-Cleanse.
b. Dumond Chemicals, Inc.; Safe n' Easy Architectural Cleaner/Restorer.
c. Price Research, Ltd.; Price Non-Acid Masonry Cleaner.
d. ProSoCo; Enviro Klean Restoration Cleaner.
G. Two-Part Chemical Cleaner: Manufacturer's standard system consisting of potassium or
sodium hydroxide based, alkaline prewash cleaner and acidic after wash cleaner that
does not contain hydrofluoric acid.
1. Available Products:
a. ProSoCo; Sure Klean 766 Limestone & Masonry Prewash and After wash.
2.5 MISCELLANEOUS MATERIALS
A. Masonry Patching Compound: Factory-mixed cementitious product that is custom
manufactured for patching masonry, is vapor and water permeable, exhibits low
shrinkage, and develops high bond strength to all types of masonry.
1. Formulate patching compound used for patching brick in colors and textures to
match brick being patched. Provide number of colors needed to enable matching
each brick.
2. Available Products:
a. Cathedral Stone Products, Inc.; Jahn Restoration Mortar.
b. Edison Coatings, Inc.; Custom System 45.
B. Liquid Strippable Masking Agent: Manufacturer's standard liquid, film-forming, strippable
masking material for protecting glass, metal, and polished stone surfaces from
damaging effects of acidic and alkaline masonry cleaners.
1. Available Products:
a. American Building Restoration Products, Inc.; LM 130 Acid Shield.
b. Diedrich Technologies Inc.; Diedrich Acid Guard.
c. Price Research, Ltd.; Price Mask.
d. ProSoCo; Sure Klean Strippable Masking.
C. Cold Galvanizing: Provide Commercial Grade ZRC (Zinc Rich Paint) to all existing
metal lintels as indicated on the drawings. Acceptable Manufacturer’s: Sherwin
Williams, Sumter Coatings, Aervoe Industries or approved equal
D. Brick Sealer: Provide Prosocco SureKlean Water Seal Masonry Sealer or approved
equal over cover the entire masonry façade not scheduled for any other sealer
application on both structures after completion of the work.
2.6 MORTAR MIXES
A. Preparing Lime Putty: Slake quicklime and prepare lime putty according to appendix to
ASTM C 5 and manufacturer's written instructions.
B. Measurement and Mixing: Measure cementitious materials and sand in a dry condition
by volume or equivalent weight. Do not measure by shovel; use known measure. Mix
materials in a clean, mechanical batch mixer.
1. Mixing Pointing Mortar: Thoroughly mix cementitious materials and sand together
before adding any 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 15 to 30 minutes. Add remaining water in
small portions until mortar reaches desired consistency. Use mortar within one hour
of final mixing; do not retemper or use partially hardened material.
C. Colored Mortar: Produce mortar of color required by using selected ingredients. Do not
alter specified proportions without Designer's approval.
1. Mortar Pigments: Where mortar pigments are indicated, do not exceed a pigment-
to-cement ratio of 1:10 by weight.
D. Do not use admixtures of any kind in mortar, unless otherwise indicated.
E. Mortar Proportions: Mix mortar materials in the following proportions:
1. Pointing Mortar for Brick: 1 part portland cement, 2 parts lime, and 6 parts sand.
a. Add mortar pigments to produce mortar colors required.
2. Rebuilding (Setting) Mortar: Comply with ASTM C 270, Proportion Specification,
Type N, unless otherwise indicated; with cementitious material content limited to
portland cement and lime.
2.7 CLEAR MASONRY ANTI –GRAFFITI SEALER:
A. Shall be breathable, water-based, VOC compliant, penetrating sealer which reacts
chemically with the substrate to form a long-lasting, water-repellant surface allowing
solvent-based spray paints, Sharpies, and permanent m arkers to be easily
cleaned off of treated surface
B. Clear, non-yellowing water repellent treatment shall not alter appearance, color, or
texture of substrate under any lighting conditions.
C. Shall be compatible with glass and protection not required.
D. Shall be compatible with landscaping/vegetation and protection not required.
E. Shall be compatible with sealants and joint sealers and protection not required.
F. Acceptable Manufacturers shall include but not be limited to: US COATING
SOLUTIONS LLC., DEFACER ERASER by Prosoco, ANTI GRAFFITI COATING by
Sherwin. or approved equal.
PART 3 - EXECUTION
3.1 PROTECTION
A. Protect persons, motor vehicles, surrounding surfaces of building being restored,
building site, plants, and surrounding buildings from harm resulting from masonry
restoration work.
1. Erect temporary protective covers over walkways and at points of pedestrian and
vehicular entrance and exit that must remain in service during course of restoration
and cleaning work.
B. Comply with chemical cleaner manufacturer's written instructions for protecting building
and other surfaces against damage from exposure to its products. Prevent chemical
cleaning solutions from coming into contact with pedestrians, motor vehicles,
landscaping, buildings, and other surfaces that could be harmed by such contact.
1. Cover adjacent surfaces with materials that are proven to resist chemical cleaners
used unless chemical cleaners being used will not damage adjacent surfaces. Use
materials that contain only waterproof, UV-resistant adhesives. Apply masking
agents to comply with manufacturer's written instructions. Do not apply liquid
masking agent to painted or porous surfaces. When no longer needed, promptly
remove masking to prevent adhesive staining.
2. Keep wall wet below area being cleaned to prevent streaking from runoff.
3. Do not clean masonry during winds of sufficient force to spread cleaning solutions to
unprotected surfaces.
4. Neutralize and collect alkaline and acid wastes for disposal off Agency's property.
5. Dispose of runoff from cleaning operations by legal means and in a manner that
prevents soil erosion, undermining of paving and foundations, damage to
landscaping, and water penetration into building interiors.
A. Prevent mortar from staining face of surrounding masonry and other surfaces.
1. Cover sills, ledges, and projections to protect from mortar droppings.
2. Keep wall area wet below rebuilding and pointing work to discourage mortar from
adhering.
3. Immediately remove mortar in contact with exposed masonry and other surfaces.
4. Clean mortar splatters from scaffolding at end of each day.
3.2 UNUSED ANCHOR REMOVAL
A. Remove masonry anchors, brackets, wood nailers, and other extraneous items no
longer in use unless identified as historically significant or indicated to remain.
1. Remove items carefully to avoid spalling or cracking masonry.
2. If item cannot be removed without damaging surrounding masonry, cut off item flush
with surface and core drill surrounding masonry and item as close around item as
practical.
3. Patch holes where items were removed unless directed to remove and replace
units.
3.3 BRICK REMOVAL AND REPLACEMENT
A. At locations indicated, remove bricks that are damaged, spalled, or deteriorated.
Carefully demolish or remove entire units from joint to joint, without damaging
surrounding masonry, in a manner that permits replacement with full-size units.
1. When removing single bricks, remove material from center of brick and work
toward outside edges.
B. Support and protect remaining masonry that surrounds removal area. Maintain flashing,
reinforcement, lintels, and adjoining construction in an undamaged condition.
C. Notify Designer of unforeseen detrimental conditions including voids, cracks, bulges,
and loose masonry units in existing masonry backup, rotted wood, rusted metal, and
other deteriorated items.
D. Remove in an undamaged condition as many whole bricks as possible.
1. Remove mortar, loose particles, and soil from brick by cleaning with hand chisels,
brushes, and water.
2. Store brick for reuse, as indicated.
3. Deliver cleaned brick not required for reuse to Agency, unless otherwise directed.
E. Clean bricks surrounding removal areas by removing mortar, dust, and loose particles
in preparation for replacement.
F. Install replacement brick into bonding and coursing pattern of existing brick, match
existing mortar joints for size. If cutting is required, use a motor-driven saw designed to
cut masonry with clean, sharp, unchipped edges.
G. Lay replacement brick with completely filled bed, head, and collar joints. Butter ends
with sufficient mortar to fill head joints and shove into place. Wet both replacement and
surrounding bricks that have ASTM C 67 initial rates of absorption (suction) of more
than 30 g/30 sq. in. per min.. Use wetting methods that ensure that units are nearly
saturated but surface is dry when laid. Maintain joint width for replacement units to
match existing joints.
1. Tool exposed mortar joints in repaired areas to match joints of surrounding existing
brickwork.
2. Rake out mortar used for laying brick before mortar sets and point new mortar
joints in repaired area to comply with requirements for repointing existing masonry,
and at same time as repointing of surrounding area.
3.4 REANCHORING VENEERS
A. Install masonry repair anchors in horizontal mortar joints and according to
manufacturer's written instructions. Install at not more than 16 inches o.c. vertically and
32 inches o.c. horizontally, unless otherwise indicated. Install at locations to avoid
penetrating flashing.
B. Recess anchors at least 5/8 inch from surface of mortar joint and fill recess with pointing
mortar.
3.5 MASONRY UNIT PATCHING
A. Patch the following masonry units:
1. Units indicated to be patched.
2. Units with holes.
3. Units with chipped edges or corners.
4. Units with small areas of deep deterioration.
B. Remove and replace existing patches, unless otherwise indicated or approved by
Owner’s designee.
C. Patching Bricks:
1. Remove loose material from brick surface. Remove additional material so patch will
not have feathered edges and will be at least 1/4 inch thick, but not less than
recommended by patching compound manufacturer.
2. Mask or remove surrounding mortar joints if patch will extend to edge of brick.
3. Mix patching compound in individual batches to match each unit being patched.
Combine one or more colors of patching compound, as needed, to produce exact
match.
4. Rinse surface to be patched and leave damp, but without standing water.
5. Brush-coat surfaces with slurry coat of patching compound according to
manufacturer's written instructions.
6. Place patching compound in layers as recommended by patching compound
manufacturer, but not less than 1/4 inch or more than 2 inches thick. Roughen
surface of each layer to provide a key for next layer.
7. Trowel, scrape, or carve surface of patch to match texture and surface plane of
surrounding brick. Shape and finish surface before or after curing, as determined by
testing, to best match existing brick.
8. Keep each layer damp for 72 hours or until patching compound has set.
3.6 CLEANING MASONRY, GENERAL
A. Proceed with cleaning in an orderly manner; work from top to bottom of each scaffold
width and from one end of each elevation to the other.
B. Use only those cleaning methods indicated for each masonry material and location.
1. Do not use wire brushes or brushes that are not resistant to chemical cleaner being
used. Do not use plastic-bristle brushes if natural-fiber brushes will resist chemical
cleaner being used
2. Power wash buildings prior to beginning any restoration work. For all work
performed on the Broad Street site, use low pressure spray only.
3. Use spray equipment that provides controlled application at volume and pressure
indicated, measured at spray tip. Adjust pressure and volume to ensure that
cleaning methods do not damage masonry.
a. Equip units with pressure gages.
4. For chemical cleaner spray application, use low-pressure tank or chemical pump
suitable for chemical cleaner indicated, equipped with cone-shaped spray tip.
5. For water spray application, use fan-shaped spray tip that disperses water at an
angle of 25 to 50 degrees.
6. For high-pressure water spray application, use fan-shaped spray tip that disperses
water at an angle of at least 40 degrees.
7. For heated water spray application, use equipment capable of maintaining
temperature between 140 and 160 deg F at flow rates indicated.
8. For steam application, use steam generator capable of delivering live steam at
nozzle.
C. Perform each cleaning method indicated in a manner that results in uniform coverage of
all surfaces, including corners, moldings, and interstices, and that produces an even
effect without streaking or damaging masonry surfaces.
D. Removing Plant Growth: Completely remove plant, moss, and shrub growth from
masonry surfaces. Carefully remove plants, creepers, and vegetation by cutting at roots
and allowing to dry as long as possible before removal. Remove loose soil and debris
from open masonry joints to depth they occur.
E. Preliminary Cleaning: Before beginning general cleaning, remove extraneous
substances that are resistant to cleaning methods being used. Extraneous substances
include paint, calking, asphalt, and tar.
1. Carefully remove heavy accumulations of material from surface of masonry with a
sharp chisel. Do not scratch or chip masonry surface.
2. Remove paint and calking with alkaline paint remover.
a. Comply with requirements for paint removal.
b. Repeat application up to two times if needed.
3. Remove asphalt and tar with solvent-type paint remover.
a. Apply only to asphalt and tar by brush without prewetting.
b. Allow paint remover to remain on surface for 10 to 30 minutes.
c. Rinse off with [cold] [hot] water using low-pressure spray.
d. Repeat application if needed.
F. Water Spray Applications: Unless otherwise indicated, hold spray nozzle at least 6
inches from surface of masonry and apply water in horizontal back and forth sweeping
motion, overlapping previous strokes to produce uniform coverage.
G. Steam Wash: Apply steam to masonry surfaces at pressures not exceeding 80 psi. Hold
nozzle at least 6 inches from surface of masonry and apply steam in horizontal back
and forth sweeping motion, overlapping previous strokes to produce uniform coverage.
H. Chemical Cleaner Application Methods: Apply chemical cleaners to masonry surfaces
to comply with chemical cleaner manufacturer's written instructions; use brush or spray
application methods, at Contractor's option. Do not apply spray at pressures exceeding
50 psi. Do not allow chemicals to remain on surface for periods longer than those
indicated or recommended by manufacturer.
I. Rinse off chemical residue and soil by working upward from bottom to top of each
treated area at each stage or scaffold setting. Periodically during each rinse, test pH of
rinse water running off of cleaned area to determine that chemical cleaner is completely
removed.
1. Apply neutralizing agent and repeat rinse, if necessary, to produce tested pH of
between 6.7 and 7.5.
J. After cleaning is complete, remove protection no longer required. Remove tape and
adhesive marks.
3.7 CLEANING BRICKWORK
A. Cold-Water Wash: Use cold water applied by low-pressure spray.
B. Cold Water Soak:
1. Apply cold water by intermittent soaking.
2. Use perforated hoses or other means that will apply a fine water mist to entire
surface being cleaned.
3. Apply water in cycles with at least 30 minutes between cycles.
4. Continue water application until surface encrustation has softened sufficiently to
permit its removal by water wash, as indicated by cleaning tests.
5. Remove soil and softened surface encrustation from masonry with cold water applied
by low-pressure spray.
C. Hot-Water Wash: Use hot water applied by low-pressure spray.
D. Steam Cleaning: Apply steam at pressures not exceeding 80 psi.
E. Detergent Cleaning:
1. Wet masonry with water applied by low-pressure spray.
2. Scrub masonry with detergent solution using medium-soft brushes until soil is
thoroughly dislodged and can be removed by rinsing. Use small brushes to remove
soil from mortar joints and crevices. Dip brush in solution often to ensure adequate
fresh detergent is used and that masonry surface remains wet.
3. Rinse with water applied by low-pressure spray to remove detergent solution and
soil.
4. Repeat cleaning procedure above where required to produce cleaning effect
established by mockup.
F. Mold, Mildew, and Algae Removal:
1. Wet masonry with water applied by low-pressure spray.
2. Apply mold, mildew, and algae remover by brush or low-pressure spray.
3. Scrub masonry with medium-soft brushes until mold, mildew, and algae are
thoroughly dislodged and can be removed by rinsing. Use small brushes for mortar
joints and crevices. Dip brush in mold, mildew, and algae remover often to ensure
adequate fresh cleaner is used and that masonry surface remains wet.
4. Rinse with water applied by low-pressure spray to remove mold, mildew, and algae
remover and soil.
5. Repeat cleaning procedure above where required to produce cleaning effect
established by mockup.
G. Nonacidic Gel Chemical Cleaning:
1. Wet masonry with water applied by low-pressure spray.
2. Apply nonacidic gel cleaner in 1/8-inch thickness by brush, working into joints and
crevices. Apply quickly and do not brush out excessively so area will be uniformly
covered with fresh cleaner and dwell time will be uniform throughout area being
cleaned.
3. Let cleaner remain on surface for period indicated below:
a. As recommended by chemical cleaner manufacturer.
b. As established by mockup.
4. Remove bulk of nonacidic gel cleaner by squeegeeing into containers for proper
disposal.
5. Rinse with water applied by low-pressure spray to remove chemicals and soil.
6. Repeat cleaning procedure above where required to produce cleaning effect
established by mockup. Do not repeat more than once. If additional cleaning is
required, use steam wash.
G. Nonacidic Liquid Chemical Cleaning:
1. Wet masonry with water applied by low-pressure spray.
2. Apply cleaner to masonry in two applications by brush. Let cleaner remain on surface
for period indicated below:
a. As recommended by chemical cleaner manufacturer.
b. As established by mockup.
c. Two to three minutes.
3. Rinse with water applied by low-pressure spray to remove chemicals and soil.
4. Repeat cleaning procedure above where required to produce cleaning effect
established by mockup. Do not repeat more than once. If additional cleaning is
required, use steam wash.
3.8 REPOINTING MASONRY
A. Rake out and repoint mortar joints to the following extent:
1. All joints in areas indicated.
2. Joints where mortar is missing or where they contain holes.
3. Cracked joints where cracks can be penetrated at least 1/4 inch by a knife blade
0.027 inch thick.
4. Cracked joints where cracks are 1/8 inch or more in width and of any depth.
5. Joints where they sound hollow when tapped by metal object.
6. Joints where they are worn back 1/4 inch or more from surface.
7. Joints where they are deteriorated to point that mortar can be easily removed by
hand.
8. Joints, other than those indicated as sealant-filled joints, where they have been filled
with substances other than mortar.
B. Do not rake out and repoint joints where not required.
C. Rake out joints as follows:
1. Remove mortar from joints to depth of 2 times joint width, but not less than 1/2 inch
or not less than that required to expose sound, unweathered mortar.
2. Remove mortar from masonry surfaces within raked-out joints to provide reveals with
square backs and to expose masonry for contact with pointing mortar. Brush,
vacuum, or flush joints to remove dirt and loose debris
3. Do not spall edges of masonry units or widen joints. Replace or patch damaged
masonry units as directed by Owner’s designee.
a. Cut out mortar by hand with chisel and mallet. Do not use power-operated
grinders without Owner’s designee 's written approval based on submission by
Contractor of a satisfactory quality-control program and demonstrated ability of
operators to use tools without damaging masonry. Quality-control program shall
include provisions for supervising performance and preventing damage due to
worker fatigue. Do not use power grinders or saws on vertical joints. All vertical
joints shall be hand tooled.
b. Cut out center of mortar bed joints using angle grinders with diamond-
impregnated metal blades. Remove remaining mortar by hand with chisel and
mallet. Strictly adhere to written quality-control program. Quality-control program
shall include provisions for demonstrating ability of operators to use tools without
damaging masonry, supervising performance, and preventing damage due to
worker fatigue.
c. Any bricks damaged by excessive or unsatisfactory mortar removal shall be
replaces at no additional cost to the Owner..
D. Notify Designer of unforeseen detrimental conditions including voids in mortar joints,
cracks, loose masonry units, rotted wood, rusted metal, and other deteriorated items.
E. Point joints as follows:
1. Rinse masonry-joint surfaces with water to remove dust and mortar particles. Time
rinsing application so, at time of pointing, joint surfaces are damp but free of
standing water. If rinse water dries, dampen masonry-joint surfaces before pointing.
2. Apply pointing mortar first to areas where existing mortar was removed to depths
greater than surrounding areas. Apply in layers not greater than 3/8 inch until a
uniform depth is formed. Fully compact each layer thoroughly and allow it to become
thumbprint hard before applying next layer.
3. After low areas have been filled to same depth as remaining joints, point all joints by
placing mortar in layers not greater than 3/8 inch. Fully compact each layer and
allow to become thumbprint hard before applying next layer. Where existing bricks
have worn or rounded edges, slightly recess finished mortar surface below face of
masonry to avoid widened joint faces. Take care not to spread mortar over edges
onto exposed masonry surfaces or to featheredge mortar.
4. When mortar is thumbprint hard, tool joints to match original appearance of joints.
Remove excess mortar from edge of joint by brushing.
F. Cure mortar by maintaining in thoroughly damp condition for at least 72 hours including
weekends and holidays.
1. Acceptable curing methods include covering with wet burlap and plastic sheeting,
periodic hand misting, and periodic mist spraying using system of pipes, mist heads,
and timers.
2. Adjust curing methods to ensure that pointing mortar is damp throughout its depth
without eroding surface mortar.
G. Where repointing work precedes cleaning of existing masonry, allow mortar to
harden at least 30 days before beginning cleaning work.
3.09 FINAL CLEANING
A. After mortar has fully hardened, thoroughly clean exposed masonry surfaces of excess
mortar and foreign matter; use wood scrapers, stiff-nylon or fiber brushes, and clean
water, spray applied at low pressure.
1. Do not use metal scrapers or brushes.
2. Do not use acidic or alkaline cleaners.
B. Wash adjacent woodwork and other non-masonry surfaces. Use detergent and soft
brushes or cloths.
C. Clean masonry debris from roof; remove debris from gutters and downspouts. Rinse off
roof and flush gutters and downspouts.
D. Sweep and rake adjacent pavement and grounds to remove masonry debris. Where
necessary, pressure wash surfaces to remove mortar, dust, dirt, and stains.
3.10 INSTALLATION OF MASONRY SEALER
A. Preparation:
1. Prepare substrates in accordance with manufacturer’s recommendations.
2. Clean surfaces by chipping and removing all the loose cement mortar.
3. Clean surfaces of dust, dirt and foreign matter detrimental to proper installation of
water repellent treatment by grinding and clean the dust using a non-compressed
air blower or industrial vacuum cleaner followed by high pressure water-jet
cleaning.
4. Protect all window surfaces. Do not apply over glass, provide adequate protection
to prevent over-spraying on windows.
B. Application
1. Add sealer concentrate to water and mix. Dilute with potable water (TDS below
1000 ppm) to obtain clear transparent solution. 23.
2. Apply at ambient temperatures of 40°F to 110°F. B.
3. Apply to wall using low-pressure non-atomizing spray. Spray until saturated; no
run down requirement 2. Pot life: 24 hours once mixed 3. Coats required: One
application 3.4
4. The entire façade of each building shall be sealed with masonry sealer in
accordance with these project specifications with the exception of those areas
scheduled for graffiti protection installation. Apply only after the building has been
completely power washed.
C. Integrity Testing
1. Test is required for all integrity testing required by architect or owner and for
expanded warranties beyond the standard 5 year material warranty.
2. The test can be done using the RILEM Test. 1. RILE M Test Method II.4 is for
measuring the volume of water absorbed by a material within a specified time
period. The test can be performed at the site for vertical or horizontal surfaces
3.11 FIELD QUALITY CONTROL
A. Inspectors: Contractor shall engage qualified independent inspectors to perform
inspections and prepare test reports. Allow inspectors use of lift devices and
scaffolding, as needed, to perform inspections.
END OF SECTION