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. • • • 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 DE 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.
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