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05400 — Masonry Cleaning  





Work included: Chemically clean the exterior brick and stone of the XXXXXXXX XXXXXXXXXX House, City, State, where shown on the Drawings, as specified herein, and as needed for complete and proper restoration.


Related Work: Documents affecting work of this Section include, but are not limited to, General Conditions, Supplementary Conditions, and Sections of Division 1 of these Specifications.


Work of this section includes the furnishing of labor, materials and equipment necessary to the cleaning of historic masonry structures (exterior).


Quality Assurance


All work shall be performed by a Contractor with demonstrated experience in the cleaning of historic architectural masonry. In addition the Contractor shall use an adequate number of skilled workmen who are thoroughly trained and experienced in the necessary crafts and who are familiar with the restoration of historic buildings and the methods needed for the proper execution of the work.


Upon request, the Contractor shall submit to the Architect a written record of all projects for which the Contractor has performed masonry cleaning.


Perform all work in compliance with codes, standards, and regulations having jurisdiction.


All work shall be done in strict accordance with the following publications:

1. Secretary of the Interior's "Standards for Historic Preservation Projects" (1995).

2. Preservation Brief No. 1: "The Cleaning and Waterproof Coating of Masonry Buildings" by Robert C. Mack.

3. Preservation Brief No. 6: "Dangers of Abrasive Cleaning to Historic Buildings" by Anne E. Grimmer.





Make submittals required by the Contract Documents, and revise and resubmit as necessary to establish compliance with the specified requirements.


Quality Assurance

1. Substitutions will be considered only when substantiated by the Contractor's submittal of required data and when submitted within thirty (30) calendar days after award of the Contract.

2. Do not substitute materials, equipment, or methods unless such substitution has been specifically approved in writing for this work by the Architect.

3. "Or equal": Where the phrase "or equal" occurs in the Contract Documents do not assume that the materials, equipment, or methods will be approved as equal unless the item has been specifically so approved for this work by the Architect. The decision of the Architect will be final.


Product Data

Within thirty (30) days after the Contractor has received the Owner's Notice to Proceed, submit:

1. Materials list of items proposed to be provided under this Section.

2. Manufacturers' specifications, literature and other data needed to comply with the specified requirements.

3. The number of copies which are required to be returned, plus one copy which will be retained by the Architect.

4. Accompany each submittal with a letter of transmittal showing all information required for identification and checking.



1. Test products approved for consideration by the Architectural Conservator shall be tested at the job. Locate masonry test areas as directed by the Architect in unobtrusive and representative areas measuring approximately sixteen (16) square feet. Test samples of adjacent non-masonry materials for effect and necessity of masking and protection.

2. Furnish samples until approval has been obtained by the Architect. Multiple tests of varying concentrations shall determine the composition of the required cleaning solutions. By single and multiple application of chemical agents to existing masonry sample areas, determine both the optimum duration of and the number of applications required to complete the work to the satisfaction and approval of the Architect.

3. The approved sample(s) shall be marked for identification and retained. Sample(s) shall constitute a standard for acceptance or rejection of completed work of this Section. Material and test patches will be approved in writing by the Architect.

4. Submit literature on water spray equipment for review.

5. All material and equipment not approved by the Architect for work of this Section shall be prohibited on job site.


Regulatory Requirements


Contractor shall be responsible for obtaining all necessary permits and the payment of associated fees.


All activities shall be in strict compliance with local and governmental regulations and codes. Activities shall include but not be limited to, execution of work, protection of property, and disposal of chemical waste and residue.


As required by state requirements, residual chemicals and water shall be contained and legally disposed of in a suitably identified hazardous waste disposal facility.


The following state agency will provide information relative to state regulations and requirements for disposal of hazardous waste.

[Applicable State agency, with address, telephone, web, contact, title.]


Product Handling


Deliver cleaning materials to the site in manufacturer's original containers with labels intact and the seals unbroken. Store materials in a locked, well ventilated storage space.


The storage space shall be kept neat and clean. Contaminated rags, containers, and refuse shall be removed and legally disposed of each day.


Environmental Conditions


No cleaning shall be done when the temperature is less than forty-five (45) degrees F, or under any condition unsuitable for the perfect execution of the work.



1. The premises will be occupied throughout cleaning operations.

2. Arrange with building custodian, with due advance notice, means for access to premises and necessary utilities and spaces for storage of equipment.

3. Provide, at all times, a covered access to building(s) for the public, employees and service vehicles.

4. Said activities shall not restrict the means of ingress or egress to the building(s).

5. Work shall conform to rules and regulations having jurisdiction.




Provide complete protection for all workers against injurious effects of cleaning agents.

1. Protection shall include but not be limited to use of goggles, rubber gloves, and plastic or rubber rainsuits to avoid splash to the skin or eyes. In addition, the Contractor shall be required to provide respirators as necessary.

2. Provide employed workers with material safety data sheets (MSDS) on all cleaning agents and procedures used on site.

3. The Contractor shall also be responsible for schooling his/her workmen in first aid procedures in case of an accident with a hazardous chemical.

4. The Contractor shall retain on site throughout cleaning operations a thorough selection of dilutants and antidotes for treatment of chemical accidents.


Throughout the cleaning operations, all adjacent materials shall be thoroughly protected form any damage whatsoever. The Contractor shall be totally responsible for repairing any damage caused by said operations.


Employ agricultural lime in conjunction with soaker hoses and copious amounts of light water spray on vegetation prior to application of any acidic cleaning compound. Thoroughly rinse area after cleaning operations.


Employ soaker hoses and copious amounts of light water spray on vegetation as part of protection procedures prior to and throughout chemical cleaning operations.


Safely contain all chemicals, rinse water, and residue resulting from cleaning procedures. Employ 6 mil. poly, pumps, plastic-lined canals/sumps to contain resulting affluent.


The Contractor is responsible for making sure the building is secure and water-tight prior to the application of chemicals/water. Take all measures to prevent water entry into the building. Employ 6 mil. plastic, duct tape, string caulking and other material as required to obtain water-tight integrity.


As required, apply approved plastic spray-on peel-off type liquid materials, plastic tarpaulins, or other type of coverings, to completely cover areas of the building that could be adversely affected. Test all protective materials against damaging affects to said building components. Use tape or appropriate sealants to close edges of covering throughout masonry cleaning operations.


The proper application and installation of protective material is extremely important. If the masking material has pin holes, gaps or any other perforations whatsoever which may allow the cleaning/rinsing agents to get behind the surface, excessive damage may result to exposed areas.


Public safety: Provide barriers and signage for the purpose of limiting public access to areas of work in progress and arrange such measures in clearly understandable ways to prevent public exposure to over-spray or contact with chemical products or contaminated rinse water.


Protect and/or divert pedestrian and automobile traffic.


The Contractor shall be held strictly responsible for all damages caused by him to any building, vegetation, fixtures, etc., as a result ofnegligence or operations.


Throughout operations, protect the marble coping from damaging effects of chemical cleaners or residue, resulting from cleaning operations of other masonry.




Clean exterior masonry prior to repointing and masonry unit replacement.