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There are a number of ways to effectively remove old
coatings and your particular job may require a combination
of approaches to get the results you want. Review the
methods explained here and see which ones best suit your
project.
 Wire Brushing
A stiff metal hand brush works well on brick, stucco and
other masonry. Used vertically it is also effective
removing paint from wood shakes. Power wire brushing can
be used on stubborn areas, but must be done with extreme
care. Wear goggles or face mask for eye protection,
leather or cloth work gloves to protect the skin, and
limit dust intake with a protective mask or respirator.
Scraping
This is a traditional effective approach for many flat
surfaces from smooth masonry and hardboard to wood and
ferrous metal.
Sanding
Areas that have been scraped should be smoothed with
sanding. A power sanding tool like an electric belt sander
is an option when the substrate is wood or steel. Do not
attempt to power sand masonry, hardboard, aluminum or
plastic materials.
Power Washing
A high pressure plain water stream is effective in lifting
old, loose paint. Never use harsh cleansers or bleach
since they can infiltrate the substrates and inhibit paint
performance. Hold the spray tip 6" to 8" from the surface.
To prevent damage, spray at a horizontal or downward angle
only, an upward angle may drive water behind siding and
even lift siding off. Power washing is not recommended for
soft woods like cedar and redwood.
Heat Gun
Old coatings such as paint and varnish can be removed with
a heat gun, but special care is required for safety. A
drop cloth should be placed on the ground under the entire
work area and must be kept damp by periodic misting with a
garden hose. Also lightly spray the area of the building
where the coating is to be removed. As the old coating
bubbles up and softens, carefully remove it with a putty
knife. Place the hot softened coating into a metal
container for disposal. Wear goggles or face mask for eye
protection; use chemical resistant gloves, long sleeve
shirt and long pants to protect the skin; and protect
breathing with a respirator designed for use with heat gun
paint removal. This article is brought to you courtesy of
the Paint Quality Institute.
Chemical Removal
Strong solvent-based removers work well on most oil-based
and latex paints, primers, stains, and varnishes. Apply a
heavy coat to a small area, about 2-4 square feet at a
time, using a low-end natural bristle paint brush. Give it
plenty of time to work as recommended by the manufacturer.
Carefully remove the softened coatings using a putty knife
or wooden blade and scrape the material into a cardboard
carton. Reapply more stripper if needed and then clean the
surface with wadded up paper toweling. Do not use steel
wool because it can discolor the treated surface. Use
these chemical removers only on small vertical and
horizontal face-up areas, such as trim and moldings.
Do not use on face-down surfaces such as porch ceilings.
Before using these products, clear the area of children
and pets.
Cover floors and steps and remove plants, rugs and
furniture. Dispose of all refuse after the job, carefully
following manufacturer instructions. Wear goggles or face
mask for eye protection; use chemical resistant gloves,
long sleeve shirt and long pants to protect the skin; and
protect breathing with a respirator designed for use with
chemical solvents. There are low odor alternatives to the
strong solvent removers, but they may take much longer,
especially if the old coatings are thick and old. |
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Painting tips & tricks of
the day
Doing clean touch ups
During light painting jobs, put a "Zip Lock" type sandwich
bag in a plastic margarine tub and fold the bag edges over
the rim. Pour the paint into the bag of your "paint tray"
and once the job is over, remove the bag and seal it, or
throw it away.
Giving old wood a fresh look
Exterior wood siding can be painted, or stripped and
painted. Strip paint using a torch by burning the old paint
and scraping it lightly being careful not to damage the
wood. Clean the surface with trisodium phosphate (TSP),
which you can find in the paint department of your local
home renovation centre. Repair siding where needed and
caulk. If you are repainting in the same colour, apply the
finishing coat after the wood is dry. If you are changing
colours, apply a primer coat followed by the new colour,
using exterior paint (an oil based primer will be necessary
if going from oil to latex). Avoid painting in full sun, at
sunset, in the early morning, in the rain or in the wind. To
keep bugs from sticking to the fresh paint, simply add two
tablespoons of citronella to the paint. |
