Are you planning on giving your home a facelift? Are you faced with peeling weatherboards and no excuse? Take heart - the job may not be as tough as it looks. And according to Resene specialists, following a few simple guidelines will help ensure painting efforts are effective, lasting and importantly, safe.
First and foremost, prepare. Exterior painted surfaces eventually break down by gradual erosion over several years, leaving a weathered or powdery surface that can be repainted after a quick wash down. Unfortunately, and for a number of reasons, this is not always the case.
Is the surface flaking, peeling or blistering?
This is one of the most common problems to overcome and if it is happening in one spot, the weakness if likely to be happening elsewhere.
To test the adhesion qualities of the surface, clean an area of the suspect coating and firmly apply a strip of sticky tape. Then quickly rip the tape off - if there is paint attached, this area must be prepared by burning, sanding or using solvent strippers. Make sure you also feather (smooth the paint edges) the area immediately around the flaking area. This will prevent the new paint from lifting in the future.
Is the surface glossy?
Some enamel paints that have aged without direct ultra-violet light become extremely hard and are difficult for new paint to adhere to. Outdoors, this might happen in sheltered areas such as under eaves and, indoors, on virtually all glossy bathroom and kitchen painted areas. In all cases, de-gloss the surface by thorough sanding.
Is the paint 'cheesy' in appearance?
Can it be easily scraped off with your fingernail? In some cases, paint simply breaks down - usually if it has been in contact with alkalis and with water for a long period. After removal of the source of the problem (for example, water leaks), the paint must be totally removed by sanding and scraping before recoating.
Is lead present?
Recent publicity has highlighted the need for care with lead-pigmented paints. It is only likely to be present in paint on houses built before 1970, on galvanised iron roofs and flashings of any age and steel structures. To remove lead-pigmented paint, take precautions such as wearing a dust mask and, if possible, wet sand or waterblast rather than dry sand. In all cases, collect any dust and debris in sealed bags for careful disposal. Avoid eating or smoking while working and wash skin, hair and clothes thoroughly at the end of each day.
Is asbestos present?
Until the early 1980s, asbestos was used in varying degrees in many textured coatings, and most fibrous cement products, such as those used for wall cladding. Removal and disposal of textured coatings is ideally handled by a specialist contractor because of the health risks involved. When preparing wallboard or roofing that contains asbestos, wear a dust mask and keep the surface wet at all times when scrubbing clean. Once dry, seal the surface with a sealer such as Resene Sureseal.
Check out the Resene Putting Your Safety First brochure for more advice on the removal of lead and asbestos.
Is it rotten underneath?
Preparing old weatherboards for painting will invariably reveal an old rotten board. Any decayed timber will have to be removed - along with 45cm of sound timber on either side. It is also a good idea to treat all the areas around and behind the cut away and rotten section with a 20% solution of Resene Moss & Mould Killer and water. Leave for up to 48 hours before rinsing clean with freshwater. Treat the replacement boards with a primer before they are fixed in place and then sand all the bare timber to provide a sound surface for priming and painting.
Take notice of the directions on paint pails and cans, especially the drying and recoating times specified. Always follow the directions and ensure surfaces are washed, clean and dry before painting. If you need more information on the area you are planning to paint, see the How to Paint Your Home section.
Be sure to make all ladders and platforms secure, put drop sheets over the front step and apply sunscreen to those bare arms and back of the neck. And do not forget to have a steady supply of something wet in the fridge - painting can be thirsty work!