How to Bleach Stains on Wood Floors
This procedure includes guidance on removing stains from wood floors using differentmethods of bleaching. These methods include using household chlorine bleach, oxalicacid, or a concentrate hydrogen peroxide solution.
NOTE: Chemical products are sometimes sold under a common
name. This usually means that the substance is not as pureas
the same chemical sold under its chemical name. The gradeof
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. Denatured Alcohol:
1. Other chemical orcommon names include Methylated
2. Potential hazards: TOXIC AND FLAMMABLE.
3. Available fromhardware store, paint store or
B. Mineral Spirits:
1. A petroleumdistillate that is used especially as a
paintor varnish thinner.
2. Other chemical orcommon names include Benzine*
(notBenzene); Naphtha*; Petroleum spirits*;
3. Potential Hazards: TOXIC AND FLAMMABLE.
4. Safety Precautions:
a. AVOID REPEATED OR PROLONGED SKIN CONTACT.
b. ALWAYS wear rubber gloves when handling
c. If any chemical is splashed onto the skin,
washimmediately with soap and water.
5. Available fromconstruction specialties
distributor,hardware store, paint store, or
C. Chlorine Bleach:
1. Other chemical orcommon names include Bleaching
solution*;Household bleach*; Laundry bleach*;
SodiumHypochlorite*; Solution of chlorinated
2. Potential Hazards: CORROSIVE TO FLESH.
3. Available fromchemical supply house, grocery store
orsupermarket, hardware store or janitorial supply
D. Oxalic Acid (COOH)2 or (H2C2O4):
1. A poisonous strongacid that occurs in various
plantsas oxalates and is used especially as a
bleachingor cleaning agent and in making dyes.
2. One of the strongestorganic acids.
3. Other chemical orcommon names include Dibasic
acid;Ethanedioic acid; Acid of sugar*.
4. Potential Hazards: TOXIC; CORROSIVE TO CONCRETE,
STEEL,WOOD OR GLASS.
5. Available fromchemical supply house, dry cleaning
supplydistributor, drugstore or pharmaceutical
supplydistributor, hardware store, or photographic
supplydistributor (not camera shop). (Often sold
undera manufacturer's brand name; the chemical
namemay appear on the label.)
E. Hydrogen Peroxide (H202): The concentratesolution used
for wood bleaching - typically soldas a two-part kit
containing sodium hydroxide.
1. An unstable compoundused especially as an
oxidizingand bleaching agent, an antiseptic, and a
2. Other chemical orcommon names include Peroxide of
hydrogen*;Solution of hydrogen dioxide*;
Superoxol*;(hydrogen peroxide is commonly sold as
a 3%solution; Superoxol is a 30% solution;
Superoxolcauses flesh burns; 3% hydrogen peroxide
doesnot). THIS PROCEDURE CALLS FOR USE OF THE 30%
3. Potential Hazards: TOXIC (when concentrated);
CORROSIVETO FLESH; FLAMMABLE (in high
4. Available fromchemical supply house, drugstore,
pharmaceuticalsupply distributor, or hardware
F. Clean, soft cloths
G. Clean, potable water
A. Glass or porcelain container
B. Stiff bristle brushes
A. Wash wood using denatured alcohol to remove anydirt or
other impurities from the surface.
B. Sand the wood and remove any paint or varnish. Brush
and/or vacuum dust and debris fromthe surface.
C. Remove any grease or oil from the surface bywashing with
mineral spirits and a clean, softcloth.
3.02 ERECTION, INSTALLATION, APPLICATION
CAUTION: DO NOT MIX AMMONIA WITH CHLORINE BLEACHES, A POISONOUS GAS WILL RESULT! DO NOT USE BLEACH ON BIRD
NOTE: TEST CLEAN A SMALL AREA BEFORE PROCEEDING WITH THEWORK TO DETERMINE THE BEST METHOD FOR REMOVING THE STAIN.
NOTE: TOTAL REMOVAL OF A STAIN MAY NOT ALWAYS BE POSSIBLE. IN THESE CASES, LIGHTENING OF THE STAIN MUST SUFFICE. ONTHE
CONTRARY, BE PREPARED FOR BLEACHED WOOD TO APPEAR LIKE-NEW IN CONTRAST TO SURROUNDING WOOD THAT APPEARS MORE AGED.
NOTE: BLEACHES ARE WATER-BASED SOLUTIONS AND TEND TO RAISE THE WOOD GRAIN WHEN APPLIED; THIS WILL REQUIRE SANDING UPON COMPLETION.
A. Stain Removal Using Household Chlorine Bleach:
Recommended for removing an anilinedye finish and ink
stains from wood.
NOTE: BE SURE TO PROVIDEPLENTY OF VENTILATION; USE
CAUTION: DO NOT MIX CHLORINEBLEACH AND AMMONIA. THIS
WILL PRODUCE A TOXIC GAS.
1. Apply bleach to thestained area using a clean,
softcloth or stiff bristle brush. Use straight
fromthe bottle; do not dilute.
2. Allow to sit on thesurface for at least 10
minutes;reapply if necessary.
3. Thoroughly rinse thesurface with clean, clear
4. Allow to dry for atleast 24 hours before
B. Stain Removal Using Oxalic Acid: Recommendedfor
removing blue ink stains, ironstains and darkening or
blackening of wood due to age orprevious cleaning.
NOTE: BEST TO USE IT WARM ANDCONCENTRATED.
1. Dissolve crystals inhot water in a glass or
2. Apply the solutionliberally to the surface using a
clean,soft cloth or stiff bristle brush.
3. Allow to sit on thesurface for at least 10
minutes. It may take longer (up to an hour) to
achieveeffective results depending on the type of
stainand type of wood; agitate with a stiff
bristlebrush if necessary to aid in stain removal;
4. Thoroughly rinse thesurface with clean, clear
5. Allow to dry for atleast 24 hours before
C. Stain Removal Using Concentrated Hydrogen Peroxide(30%):
Recommended for lightening woods oras a last attempt at
removing a stain before resortingto replacement.
NOTE: HYDROGEN PEROXIDE ATTHIS CONCENTRATE IS THE
STRONGEST OF THE THREE BLEACHESLISTED. IT IS TYPICALLY
SOLD AS A TWO-PART KIT CONTAININGSODIUM HYDROXIDE.
1. Dampen the woodusing a sponge soaked in clean,
2. Apply mixture ofhydrogen peroxide and sodium
hydroxideuniformly over the surface. Follow
manufacturer'srecommendations for application
proceduresand dwell time.