DEALING WITH LEAD
Repairing Timber Rot
All rot must be cut out and replaced. You can never fill or paint over it.
• Cut well back from the visible rot on weatherboards 600mm on each side.
• Make sure you get all the rot out. Also check behind the framing, it may extend
into the stud framework as well.
• Paint lots of timber preservative onto any timber exposed by cutting. Even
spray preservative around the wall cavity if it’s not full of insulation.
• Replace damaged building paper as tape laps.
• Prime exposed timber with oil-based primer.
• Replace rotten timber with treated timber (H 3.1 minimum).
• Glue and screw with waterproof glue (splicing into sills) or screw back with a
flexible exterior sealant in the joints.
• Sand the joint smooth and level, then prime.
Try and minimise the amount of paint dust. Scraping with a tungsten
scraper or burning off is best.
SANDING LEAD-BASED PAINT
•
Wear a dust mask, and use an electric sander that has an efficient
dust bag fitted.
•
ONLY wear work clothes for stripping paint. Take them off as soon
as you finish each day, wash frequently and separately from other
clothes. Shower thoroughly, immediately after work. Wash hands
before eating.
CHOOSING FILLERS
•
•
Check the label, or ask for advice from PlaceMakers staff to ensure
you have the correct filler for your needs.
•
Where a flexible filler has to seal against regular water runoff, for
instance between the timber upstand around a bath and wallboard,
use a product specifically designed to seal against moisture.
Close doors and windows to prevent lead getting inside.
•
Use drop sheets (fireproof) to catch debris.
Sanding Smooth and Providing a Key
•
Collect spilt debris with commercial wet and dry vacuum cleaner.
A surface should be smooth but not glossy before painting. Paint won’t stick well
to a glossy surface. Careful sanding will smooth out any irregularities and
provide a “key” for the new paint.
Sealing Interiors
Make sure any filler you use is paintable.
Old paintwork
•
•
•
Rub down sound old paintwork with 120 or finer grit paper.
Feather out the paint around any bare areas.
If repainting with gloss paint, use 200 grit wet and dry paper on existing
glossy paint.
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•
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www.placemakers.co.nz
Bare GIB® should be sealed prior to applying top coats. If it is a brand new surface
you can use an acrylic sealer undercoat. If the surface is sunburnt (the face of the
board has been exposed to sunlight for 2-3 weeks and has gone yellow) or old
(older than 12 weeks) it must be sealed with an oil-based pigmented sealer, this
also applies to all GIB plasterboards.
Stripping Wallpaper
Stripped timber
Updated: Feb 2009 (FM0802 02/09)
BURNING OFF LEAD-BASED PAINT
•
•
Please Note:
While the advice and recommendations contained in this brochure
have been produced with proper care, they are offered only with
the objective of assisting those interested in home improvement
projects. PlaceMakers does not accept responsibility for the advice,
recommendations, etc. contained herein.
Don’t let children or animals play in the dust. Collect it in a strong
plastic bag and deposit at the toxic waste section of your local tip.
Sand the whole surface to smooth out any irregularities.
Always sand in the “Iong” direction of the board.
Clean off all sanding dust before painting.
LEAD IS DANGEROUS
Lead was used in paints up until the early ’80s. So many houses that
are now ready to be stripped are covered with lead-based paint. If any
is swallowed or inhaled, it can cause illness and death.
Test for lead by cutting into the existing paintwork at an angle with a
sharp blade, exposing all the layers of old paint. Drip some 5% sodium
sulphide solution (available from pharmacies) into the cut.
Paint containing lead will go black. Testing kits are also available at
PlaceMakers.
Painting over the top of wallpaper is not recommended, it can make it difficult to
remove later. To strip off wallpaper, use wallpaper strippers in conjunction with a
pump up garden spray unit.
Spray the first two drops of wallpaper with the solution allowing it to soak in and
release the glues. The secret is to not allow the solution to dry, but keep it activated.
Spray the first and second drop again and you should be able to remove the
first drop.
Once you have removed the first drop spray the second and third, and then start to
remove the second drop. If you follow around the room in this fashion, the wallpaper
should be a lot easier to remove.
When you have all the paper off, wash the walls down with sugar soap and water,
then flush off with fresh water and allow them to dry. When dry, seal the walls with
oil-based pigmented sealer but this will require lining paper before painting.
PUTTING UP A
PREPARING
TO PAINT
YOUR COMPLETE KNOW HOW
W GUIDE
GUI
UIDE
UIDE
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GETTING STARTED
Preparation
Preparation is the key to a good paint job. No m
matter
atte
at
t rh
te
ho
how
ow
good you may be with a brush, roller or spray unit,
unit
it, iff your
it
yo
your
ou
preparation is not up to scratch, the finished job will be of
poorer quality.
Paint preparation involves five main processes.
• Cleaning the surface well
• Stripping off unstable or rough existing finishes
• Filling all holes, gaps, cracks and defects
• Sanding to provide a key or grip for the new paint
• Sealing and or priming the surface.
Not all are necessary in every case.
Poorly prepared surfaces will require repainting sooner and
will take more work to prepare the surface than if you had
correctly prepared them in the first place.
Preparing includes washing down, sanding, rust removal,
removal of peeling, flaking and cracked paintwork, and the
removal of all contaminants such as mould, lichen, moss
and atmospheric particles (salt deposits, grease, soot,
etc. just to name a few). By following the recommended
procedure on the back of the paint can and in brochures,
failures can be avoided from the onset.
Tools
Sandpaper: 80, 100,
150 & 200 grit and
sanding block
Hand scrapers:
preferably tungsten
blades
Paintable flexible filler
and caulking gun
STRIP BACK TO BARE TIMBER WHEN:
Cleaning
The first and most important part is to remove all contaminants by washing the
surface with the appropriate mould killer or sugar soap, making sure that you
rinse the surface with fresh water before the solution can dry. This is done to
make sure you are not introducing more contaminants to the surface which will
inhibit adhesion of the new paint. Once you have finished washing the surface
thoroughly, allow to dry before you proceed to the next step.
the existing paint fails the adhesion test.
•
any defects in existing paintwork will show through new paint.
•
paint is cracked, blistered or peeling.
•
build up on door and window frames prevents their closing.
•
using a much darker colour than previously.
The ideal time to repaint a weatherboard, fibre cement or concrete block house, is when
the existing paint surface is sound but powdery, and bare substrate is not exposed.
Where all the old paint needs to come off (usually outside), the best removal
method depends on the type of substrate and whether the paint is water-based
(acrylic) or oil-based (alkyd).
To test for water or oil-based paint
Rub the paintwork hard with a rag dipped in methylated spirits. If the paint colour
comes off on the rag, it’s almost certainly water-based.
Stripping
Check the existing paint surface. Can it be rubbed down and painted over, or does
it need to be stripped back to the bare substrate?
If the paintwork is cracked, flaking or peeling, chances are the rest of the surfaces
could be the same. If you try to paint over unsound surfaces, the new paint will
apply pressure to the old coating, which will then start to crack and peel again.
An easy test to check old paint is to place an X cut in the paintwork at various
areas around the house, stick tape down well across the cut and peel off quickly.
If the paint peels off with the tape then removal of the coating is necessary.
(See Illustration 1).
Medium and narrow
scraper/flat knife
Stripping Back
Timber
For water-based paint only, a hot air gun works passably well. For oil-based paint
a naked flame (LPG fuelled blowtorch), hand sanding and machine sanding all
work well. However, only the blowtorch or a commercial grade hot air gun are
practical for large areas.
Corrugated metal roofing
Hand scraping, and hand or machine sanding all remove paint well. However
they will also damage the protective galvanised coating, as will wire brushing. It is
better to use a water blaster. Although it won’t remove all paint, any that adheres
after blasting can be painted over.
Take care to work down the roof, and in the direction of the laps to avoid forcing
water up under the overlapping sheets.
Stucco
Rigid exterior filler
Sugar soap or Basol
crystals
•
LPG bottle and blow
torch or hot air gun
(higher wattage the
better)
Dust mask
Check to see if your
old paint is in good
condition by making
several cuts with a
sharp knife.
Press a piece of strong
adhesive tape across
the area and peel it off.
Appropriate sealers,
primers and brushes
Illustration 1: Check Existing Paintwork
If the paint comes
off with the tape, the
surface should be
stripped, sanded or
scraped back to bare
wood if possible.
Remove any loose building paper, bird’s nests or anything that is
flammable, contact your local fire service and stop work at least two
hours prior to going inside, so that if there is anything smouldering you
will notice it before you leave the job. Do not work in windy conditions.
Mechanical sanders, hand sanders and scrapers may be better options
with fewer hassles (worrying about fires). Some surfaces may be fine
and only require a light sand or wash down prior to painting. This often
applies to surfaces such as fibre cement boards, concrete blocks and
textured surfaces.
Filling
For a flawless finish, fill every gap, crack, hole and dent. It produces a much better
looking paint job, restricts insect entry and protects the house from moisture
damage. Holes allow water in, exposing untreated timber to rot.
Rigid or flexible fillers?
For holes in solid surfaces such as plasterboard, fibre cement, stucco,
weatherboard: fill with a suitable hard setting filler that is plaster based or fibreglass. For gaps with potential to move, such as between architrave and wall
linings, facing and weatherboards, cornice and ceiling, or for a crack in timber, fill
with a paintable flexible filler.
Interior use
Extensive fine cracks, chips or small holes in plasterboard can be filled with a
plaster based filler like SKIM COAT. For bigger holes use a filler like PERMAFILL
or RAPIDFILLA. For really large holes, do a proper repair, by cutting out damaged
section and replacing with a patch. Use a tube filler like NO MORE GAPS to fill
cracks and gaps that might move.
Exterior use
Fibre cement
For masonry surfaces use a cement based filler like NO MORE GAPS MASONRY.
All must be undercoated before the top coat is applied.
Other Surfaces:
Utility knife and strong
sticky tape
If you are considering using an LPG fuelled blowtorch, it can be very
easy to set your house on fire. Always have a garden hose standing by
in case of fire and make sure your insurance covers you for this type of
work before you start.
Clean off small isolated patches of flaking or chalking paint with a wire brush. For
extensive areas of degraded paint, use a waterblaster and an anti-fungal solution.
Hand scraping and hand sanding both work well to remove loose paint or strip
small areas. Old asbestos fibre board should NEVER be scraped or sanded.
Linseed oil putty
BLOWTORCH PRECAUTIONS
Other surfaces like internal linings and woodwork don’t generally need to be
completely stripped in order to be repainted, hand sanding or scraping in usually
the best in these cases. If you want to totally strip old skirting, doors and window
joinery, experiment with a combination of chemical strippers, hand scrapers and
small specialist power sanders.
For holes in timber where there will be no movement, use a rigid plaster based
exterior filler like PERMAFILL or fibreglass BUILDERS BOG.
Where there is likely to be movement, use a flexible filler like NO MORE GAPS
or externally a sealant.
Rusty nail holes can bleed through several layers of paint. Punch them below the
surface. Spot prime with an oil-based galvanised iron primer. Fill with linseed oil
putty, and then prime over the top.
Where glazing putty is missing or needs replacing, prime wooden frame first then
replace with new linseed oil putty. Leave to harden for two weeks before repainting.