Cleaning And Stripping Paint From Plaster Surfaces

CLEANING AND STRIPPING PAINT FROM PLASTER SURFACES


BEFORE UNDERTAKING ANY PROJECT INVOLVING PAINT REMOVAL, APPLICABLE
STATE AND FEDERAL LAWS ON LEAD PAINT ABATEMENT AND DISPOSAL MUST
BE
TAKEN INTO ACCOUNT AND CAREFULLY FOLLOWED. STATE AND FEDERAL
REQUIREMENTS MAY AFFECT OPTIONS AVAILABLE TO OWNERS ON BOTH PAINT
REMOVAL AND REPAINTING. THESE LAWS, AS WELL AS ANY REQUIREMENTS
PROHIBITING VOLATILE ORGANIC COMPOUNDS (VOCs), SHOULD BE REQUESTED
FROM THE ENVIRONMENTAL PROTECTION AGENCY AND/OR THE STATE OFFICE OF
ENVIRONMENTAL QUALITY.

(FOR REFERENCE SEE: National Park Service Preservation Brief 28, “Painting Historic Interiors”).

PART 1–GENERAL

1.01 SUMMARY

A. This procedure includes guidance on cleaning and
chemically removing paint from existing plaster surfaces.

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

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).


PART 2–PRODUCTS

2.01 MANUFACTURERS

A. Diedrich Technologies, Inc.
www.diedrichtechnologies.com

B. Red Devil, Inc.
www.reddevil.com

2.02 MATERIALS

NOTE: Chemical products are sometimes sold under a common
name. This usually means that the substance is not as pure as
the same chemical sold under its chemical name. The grade of
purity of common name substances, however, is usually adequate
for stain removal work, and these products should be purchased
when available, as they tend to be less expensive. Common
names are indicated below by an asterisk (*).

A. Trisodium Phosphate:

NOTE: THIS CHEMICAL IS BANNED IN SOME STATES SUCH AS
CALIFORNIA. REGULATORY INFORMATION AS WELL AS
ALTERNATIVE OR EQUIVALENT CHEMICALS MAY BE REQUESTED FROM
THE ENVIRONMENTAL PROTECTION AGENCY (EPA) REGIONAL OFFICE
AND/OR THE STATE OFFICE OF ENVIRONMENTAL QUALITY.

1. Strong base-type powdered cleaning material sold
under brand names, such as that manufactured by Red
Devil, Inc.

2. Other chemical or common names include Sodium
Orthophosphate; Tribasic sodium phosphate;
Trisodium orthophosphate; TSP*; Phosphate of soda*.

3. Potential Hazards: CORROSIVE TO FLESH.

4. Available from chemical supply house, grocery store
or supermarket or hardware store.

B. Commercial paint remover, such as “Diedrich 400 - Enviro-
Safe Strip” (Diedrich Technologies, Inc.), or approved
equal.

C. For Glaze Remover:

1. Denatured Alcohol:

a. Other chemical or common names include
Methylated spirit*.

b. Potential hazards: TOXIC AND FLAMMABLE.

c. Available from hardware store, paint store or
printer’s supply distributor.

d. Denatured alcohol should be a satisfactory
substitute for ethyl alcohol for stain
removing purposes.

2. Mineral Spirits:

a. A petroleum distillate that is used especially
as a paint or varnish thinner.

b. Other chemical or common names include
Benzine* (not Benzene); Naphtha*; Petroleum
spirits*; Solvent naphtha*.

c. Potential Hazards: TOXIC AND FLAMMABLE.

d. Safety Precautions:

1) AVOID REPEATED OR PROLONGED SKIN CONTACT.

2) ALWAYS wear rubber gloves when handling
mineral spirits.

3) If any chemical is splashed onto the
skin, wash immediately with soap and
water.

e. Available from construction specialties
distributor, hardware store, paint store, or
printer’s supply distributor.

3. Acetone (C3H6O):

a. A volatile fragrant flammable liquid ketone
used chiefly as a solvent and in organic
synthesis and found abnormally in urine.

b. Other chemical or common names include
Dimethyl ketone; Propanone

c. Potential Hazards: VOLATILE AND FLAMMABLE
SOLVENT

d. Available from chemical supply house or
hardware store.

D. Clean, potable water

2.03 EQUIPMENT

A. Clean, dry cloths

B. Sponge or heavy-nap cloth

C. Soft, fiber bristle brushes

D. Putty knife


PART 3–EXECUTION

3.01 PREPARATION

A. Protection:

1. Protect surrounding surfaces from damage resulting
from chemical cleaning and paint stripping work.

2. Dispose of by-products from cleaning and paint
stripping operations by legal means and in manner
which prevents damage to other surfaces.

3. Develop a work plan indicating recommended
treatments for surfaces/areas.

B. Surface Preparation: Prior to cleaning and stripping
work, remove cellophane tape, masking tape, etc. from
surface.

3.02 ERECTION, INSTALLATION, APPLICATION

A. Cleaning Existing Plaster Surfaces:

1. Mix TSP with warm water to create cleaning
solution.

2. Scrub surface with a cloth, sponge or soft-fibered
brush and cleaning solution.

a. Proceed with cleaning and stripping in an
orderly manner; work from bottom to top of
each surface and from one end of each surface
to the other.

b. Perform each cleaning and stripping method
indicated in a manner which results in uniform
coverage of all surfaces, including corners,
moldings, interstices and which produces an
even effect without streaking or damage to
surfaces.

3. Sponge rinse surface thoroughly using clean water
to completely remove chemical residue and soil.
Change rinse water frequently.

a. Rinse off chemical residue and soil by working
upwards from bottom to top of each surface and
from one end of each surface to the other.

NOTE: THERE IS SOME DIFFERENCE OF OPINION AS
TO WHETHER IT IS BEST TO WASH A WALL WORKING
FROM THE TOP DOWN OR FROM THE BOTTOM UP.
BOTTOM UP IS SAFER BECAUSE SOLUTION STREAKS
RUNNING DOWN ON A DIRTY WALL CANNOT BE
REMOVED. THE IMPORTANT THING IS TO WORK DRY
ENOUGH TO AVOID DRIPS.

4. Repeat process as required.

5. Wipe the surface with a dry clean cloth to prevent
streaking.

B. Stripping Paint from Plaster Surfaces:

1. Carefully apply commercial stripper to painted
surface with a brush. Follow manufacturer’s
instructions and precautions.

-OR-

Prepare a glaze remover: Mix 5 parts denatured
alcohol, 3 parts mineral spirits and 1 part acetone
and apply to the surface.

2. Allow commercial stripper or glaze remover to
remain on surface for length of time recommended by
manufacturer and required to emulsify paint build-
up.

3. Carefully remove emulsified paint with a putty
knife.

4. Repeat process as many times as required to remove
paint build-up.

5. Neutralize chemical stripper by wiping surface with
a cloth wet with clean water. Change water
frequently.

3.02 ADJUSTING/CLEANING

A. Upon completion of this work, all floors, walls and other
adjacent surfaces that are stained, marred, or otherwise
damaged by work under this section shall be cleaned and
repaired and all work and the adjacent areas shall be
left in a clean and perfect condition.

B. All completed work shall be adequately protected from
damage by subsequent building operations and effects of
weather. Protection shall be by methods recommended by
the manufacturer of installed materials and as approved
by the RHPO.