Removal Of Ferrous Staining From Brick, Granite, Concrete And Limestone
- Procedure code:
- National Capitol Region Specifications - Cohen Building
- Unit Masonry
- Last Modified:
REMOVAL OF FERROUS STAINING FROM BRICK, CONCRETE AND LIMESTONE
PART 1--- GENERAL
A. This procedure includes guidance on removing ferrous
staining from exterior brick, concrete and limestone
1. Remove soiling, stains and crusts from the
limestone and granite without damaging underlying
material and to give all stone a clean, uniform
appearance without blotches, streaks or other
irregularities. Use the gentlest means to meet the
2. If the exterior masonry has been previously
subjected to inappropriately harsh and uneven
cleaning, it is expected that the cleaning will
reveal the original colors and textures of the
brick, but that it will not completely correct the
differential effects of the previous cleaning.
Clean brick to remove soiling, stains and crusts to
the extent feasible without further damaging the
B. 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
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. Diedrich Technologies, Inc.
B. ProSoCo, Inc.
A. Ferrous-Based Stain Remover: Commercially available
liquid stain removing compound made up of blended organic
acids in combination with special chelating and wetting
agents specifically formulated for treatment and removal
of metallic oxides from masonry, such as "Sure Klean
Ferrous Stain Remover" (ProSoCo, Inc.), or approved
B. 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.), or approved equal.
C. Water: Potable, non-staining and free of oils, acids,
alkalis and organic matter.
A. Brushes: Natural fiber bristle only. The use of wire
brushes or steel wool is not permitted.
A. Protection: Protect the surfaces below the sections of
masonry to be cleaned of ferrous stains from run-off
using liquid strippable masking agent.
B. Surface Preparation:
1. Commence ferrous stain removal immediately after
general cleaning of masonry (see 03710-15-R, 04211-
04-R, and 04460-03-R for guidance on the general
cleaning of concrete, brick and limestone
2. Proceed from the top of the wall downward. Work
shall not be considered complete until the
Contracting Officer's representative has so
notified the Contractor in writing.
3. Filter the water with a 5 micron particulate filter
placed in line with the water supply. Replace the
filter as needed during the work.
3.02 ERECTION, INSTALLATION, APPLICATION
A. Prewet wall with clean, clear water immediately before
applying ferrous-based stain remover.
B. Apply ferrous-based stain remover with natural fiber
bristle brush. Allow to dwell on the surface for three to
C. Rinse all traces of chemical and residue with pressurized
cold water. Repeat procedure if necessary. Rinse water
pressure shall not exceed 300 psi, and shall be sprayed
through nozzles fitted with 15 to 20 wide nozzle 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 gauges.
D. Repeat procedure if necessary to remove all traces of
END OF SECTION