Removing Paint From Granite

Procedure code:
National Capitol Region Specifications
Last Modified:




    A.   This procedure includes guidance on removing paint from
         granite surfaces.

    B.   Safety Precautions:  
         1.   The work specified herein requires knowledge of
              older materials and methods and a high degree of
              skill to execute properly.  This work should be
              performed only by an experienced, pre-qualified
              contractor.  It is not recommended that building
              maintenance personnel perform this work.
         2.   This outline specification contains recommended
              materials which may be toxic.  The manufacturer's
              literature on application techniques, appropriate
              protection for workers and disposal procedures for
              materials should be complied with in conjunction
              with all regulatory requirements referenced in this
    C.   See 01100-07-S for general project guidelines to be
         reviewed along with this procedure. These guidelines
         cover the following sections:

         1.   Safety Precautions

         2.   Historic Structures Precautions

         3.   Submittals

         4.   Quality Assurance

         5.   Delivery, Storage and Handling

         6.   Project/Site Conditions

         7.   Sequencing and Scheduling

         8.   General Protection (Surface and Surrounding)

         These guidelines should be reviewed prior to performing
         this procedure and should be followed, when applicable,
         along with recommendations from the Regional Historic
         Preservation Officer (RHPO).  


    A.   Product Data:  
         1.   Submit manufacturer's product literature
              instructions for use, and Material Safety Data
              Sheets(MSDS) to the Contracting Officer or the
              designated representative for all cleaning
         2.   Prior to commencing the cleaning operations, the
              Contractor shall submit to the Contracting Officer
              or the designated representative a written
              description of the entire methods and procedures
              proposed for cleaning the masonry including, but
              not limited to:  Method of application, dilution of
              application, temperature of application, length of
              time of surface contact, method of rinsing surface
              (temperature, pressure, and duration), repetition
              of procedures, etc.
         3.   Prior to commencing the cleaning operations, the
              Contractor shall submit to the Contracting Officer
              or the designated representative for approval, a
              written description of proposed materials and
              methods of protection for preventing damage to
              adjacent materials, vehicular and pedestrian
              traffic, and the building interior during the
              cleaning of masonry.
    B.   Samples:
         1.   The Contractor shall clean a sample panel(s),
              approximately 3' x 3' in area, on each type of
              masonry included in the work of this section for
              approval by the Contracting Officer.  Locations of
              sample panels to be selected by the Contracting
              Officer or the designated representative.
         2.   Adjust the chemical concentrations, working
              pressures and methodologies during test panel
              cleaning, as directed by the Contracting Officer or
              the designated representative.
         3.   Sample panels shall be cleaned by the Contractor
              using methods, materials, and working pressures
              previously submitted and approved.  Sample panel
              cleaning shall be performed in the presence of the
              Contracting Officer or the designated
              representative.  The working pressures during
              sample panel cleaning shall be varied up to the
              previously submitted and approved capacities to
              determine the best working pressure.
         4.   Where chemical cleaners and poultices are tested,
              the manufacturer's representative shall be present
              during testing.
         5.   The Contractor shall obtain written approval from
              the Contracting Officer or the designated
              representative of cleaning methods, working
              pressures, materials, equipment used and sample
              panels before proceeding with building cleaning
              operations.  For this written approval purpose, the
              Contractor shall allow a minimum of seven calendar
              days after completion of sample cleaning to permit
              the Contracting Officer of the designated
              representative to study the sample panels for
              negative reaction.  Retain approved panels in
              unaltered condition, suitably designated during
              construction as a standard for judging completed


    A.   Qualifications:
         1.   General Objective: The objectives of masonry
              cleaning are to remove dirt, grime and coatings
              from masonry without damaging underlying material
              and to give all masonry a clean, uniform appearance
              without blotches, streaks, runs, or any other kind
              of spotty appearance.  Too aggressive cleaning
              shall not be acceptable.          
         2.   Cleaning Standard:  Prepare sample panels for
              approval which shall establish a standard for
              general brick and stone cleaning.  General cleaning
              shall not commence until written approval is
              obtained from the Contracting Officer or the
              designated representative.
         3.   Contractor:  The work of this section shall be
              performed by a specialist possessing a minimum of
              five (5) years of specialized experience in the
              cleaning of historic architectural masonry similar
              to that which is required by this project.
              Contractors shall submit to the Contracting Officer
              or the designated representative references of
              previous work justifying their experience.  The
              Contracting Officer or the designated
              representative reserves the right to approve or
              disapprove the use of Contractors contingent upon
              their experience.
         4.   In the event that the Contractor wishes to modify
              any cleaning method specified, he shall submit his
              proposal in writing for consideration and review.
              The Contracting Officer of the designated
              representative will have the right to ask for test
              samples before final approval.  Any such
              modifications or changes shall be at no additional
              cost to the Government.

    B.   Regulatory Requirements:  Comply with municipal and
         Federal regulations governing the cleaning, chemical
         waste disposal, product safety, scaffolding and
         protection to workers and adjacent properties.


    A.   Environmental Requirements:
         1.   No cleaning shall be executed when air or masonry
              surface temperature is below 45 degrees F, unless adequate,
              approved means are provided for maintaining a 45 degrees F,
              temperature of the air and materials during, and
              for 48 hours subsequent to, cleaning.
         2.   Perform cleaning and washing of the exterior
              masonry only during hours of natural daylight.



    A.  ProSoCo, Inc.

    B.  Diedrich Technologies, Inc.


    A.   Paint Remover:  Commercially available alkaline/solvent
         compound designed specifically for removing paint and
         graffiti from porous masonry surfaces, such a "Sure Klean
         Ferrous Stain Remover" (ProSoCo, Inc.), or approved

         Paint remover should have the following characteristics:
         Form:     Light brown gel
         Specific Gravity: 1.295
         Wt./Gal.: 10.8 lbs.
    B.   Masonry Cleaner:  Commercially available very mild blend
         of inhibited acidic ingredients and wetting agents
         specifically formulated for restorative cleaning of brick
         and natural stone surfaces, such as "Sure Klean
         Restoration Cleaner" (ProSoCo, Inc., Kansas City,
         Kansas), "101-G Granite, Terra Cotta and Brick Cleaner"
         (Diedrich Technologies, Inc.), or approved equal.

         Cleaner should have the following physical
         Form:     Clear liquid
         pH:  1.2
         Specific Gravity (Typical): 1.05

    C.   Liquid Strippable Masking Agent:  Manufacturer's standard
         liquid, film forming, strippable masking material for
         protecting glass, metal and polished stone surfaces from
         damaging effect of acidic and alkaline masonry cleaners,
         such as "Sure Klean Strippable Masking", (ProSoco, Inc.),
         "Diedrich Acid Guard", (
Diedrich Technologies, Inc.), or
         approved equal.
    D.   Water:  Potable, non-staining and free of oils, acids,
         alkalis and organic matter.

    E.   Clean, soft cloths

    A.   Brushes:  Natural fiber bristle only.  The use of wire
         brushes or steel wool is not permitted.
    B.   Garden hose with fan tip nozzles



    A.   Protection:

         1.   Take all necessary precautions and measures to
              protect surrounding materials on the site, surfaces
              of the building not being cleaned, adjacent
              buildings, pedestrians and vehicles from coming in
              contact with cleaning chemicals, over spray, or
              runoff.  Products used for masonry cleaning may be
              harmful to painted, polished, glazed, or metallic
              surfaces.  Any damage to materials caused by the
              cleaning operations is unacceptable and shall be
              repaired or replaced by the Contractor to the
              satisfaction of the Contracting Officer or the
              designated representative at no cost to the
         2.   Provide protection from water damage to building,
              structure, or building contents as required.
         3.   Protect trees and plants around the building from
              contamination or damage as directed by the
              Contracting Officer or the designated
              representative.  The Contractor shall be
              responsible for replacing with new stock, any
              trees, shrubbery or grass damaged by the cleaning
         4.   Test all drains and other water removal systems to
              assure that drains and systems are functioning
              properly prior to performing any cleaning
              operations.  Notify Contracting Officer or the
              designated representative immediately of any and
              all drains or systems that are found to be stopped
              or blocked.  Contractor shall repair drains if so
              directed by the Contracting Officer or the
              designated representative.  Do not begin work of
              this Section until the drains are in working order.

         5.   Provide a method to prevent solids such as stone or
              mortar residue from entering the drains or drain
              lines.  Contractor shall be responsible for
              cleaning out drains and drain lines that become
              blocked or filled by sand or other solids because
              of work performed under this Contract.


    A.   Commence paint removal immediately before general

         cleaning of masonry.
    B.   Apply a heavy coat of paint remover to painted surfaces
         using a synthetic fiber brush or roller.
    C.   Allow paint stripper to remain on the surface for four
         hours or until the paint is obviously "lifted" or
    D.   Thoroughly rinse the paint stripper and solubilized
         paint from the surface with pressurized cold water.
         Rinse water pressure shall not exceed 300 psi and shall
         be sprayed through nozzles fitted with 15-20" wide fan
         tips.  Nozzles shall be held perpendicular to the
         surface at a working distance of 1.5 to 2.5 feet. All
         pressure pumps shall be equipped with working pressure

    E.   Repeat procedure as necessary to remove all traces of
         paint from granite.
    F.   When all paint has been removed, apply masonry cleaner
         diluted 1 part cleaner to 6 parts water to remove all
         traces of stripper and "pigment shadow" left in the pores
         of the masonry and to neutralize any alkaline residues
         that may cause an unsightly white haze.

    G.   Allow cleaner to remain on surface 1 to 2 minutes.
    H.   Thoroughly rinse masonry cleaner with pressurized cold
         water.  See 3.01 D. above.
                         END OF SECTION

Last Reviewed 2012-06-14