Painting and decorating can make your home more attractive, and make walls and other surfaces more durable. You’ll be protecting against wear and tear and the effects of exposure to airborne moisture and the elements.
Good preparation will improve the appearance of your finishes, and is key to their longevity and durability.
If you’re renovating an older home, remember that paint from the 1970s and earlier often contained lead pigments, so take extra care when scraping, sanding and stripping older paint surfaces. Make sure you keep small children and pets away from the area.
Exposure to even small amounts of lead can result in lead poisoning and cause severe health problems. The risks are even greater for small children, as they are more likely to end up with the dust in their mouths.
Lead and lead poisoning on the Auckland Regional Public Health Service website has more details on lead poisoning symptoms.
You can check if paintwork contains lead by using a test kit – you can find these at home improvement and paint stores.
If you do find paint that contains lead, you can take a few simple steps to reduce the risk of exposure while you’re working and cleaning up. Wear a dust mask or respirator, goggles, a hat to prevent dust getting in your hair, and keep your skin covered. Dust masks and respirators should meet the joint Australian and New Zealand Standard AS/NZS 1716: 2012 – it should say on the packet or mask if it complies.
Anyone who has been exposed to the dust should carefully wash their hands and face before eating food. Wet sanding is helpful in reducing the amount of dust getting airborne.
Make sure that any paint dust or scrapings are carefully contained and disposed of – ask your local council if it has any rules around the disposal of paint dust or scrapings. If you’re working outside, be sure to remove any paint flakes or scrapings from your garden.
For more information, check out the Ministry of Health’s webpage on Removing lead-based paint
Choosing a product
There are a wide variety of products available to suit a wide range of purposes. However, some ingredients in painting and decorating products can have significant environmental impact during manufacture, could be harmful to humans during use and after application, or may create problems during disposal.
Look for products that are endorsed with independent environmental labels that provide information on:
- toxicity, emissions and air quality
- sustainability and life-cycle
- efficiency and functionality
- recyclability, reuse and waste minimisation.
Toxicity, emissions and air quality
Paints, wall coverings, sealers and finishes are made from a variety of ingredients that can include:
- colouring agents or pigments
- binders such as acrylic, polyester and polyvinyl chloride (PVC)
- plant fibres (paper, textiles)
- additives and extenders
- plasticisers (for flexibility).
Some of these ingredients can be synthetic or based on plant, mineral or animal products. Synthetic ingredients can be made from a range of chemical substances.
Before you choose a product, ask to see its safety data sheet (SDS) or check for it on the manufacturer’s website. This will provide a range of information about the product, including possible health and environmental effects relating to the product, and safety precautions during transport and handling.
Safety information is available on the Environmental Protection Authority website.
Volatile organic compounds (VOCs) are chemicals that become airborne and therefore breathable at room temperature.
Water-based products have lower solvent emissions and are less harmful to use and dispose of. Water-based acrylic paints and finishes can still contain VOCs, so check the label for the VOC level (or the percentage of hydrocarbon solvent). To be licensed to use the Environmental
Choice New Zealand label, paint must, among other things, contain no more than 20 per cent hydrocarbon solvents by weight.
Solvent-based products such as oil-based enamel paints, and some varnishes, can release significant levels of VOCs during and after application – polyurethane can give off VOCs for years. Mineral turpentine may be used as a solvent in the paint and as a paint thinner, and can contain benzene which is known to cause cancer.
There are paints available that contain no or low VOCs. Natural, plant-based paints and finishes can use plant oils based on citrus or tree oils and natural turpentine – these release low levels of VOCs.
Pigments add colour and finish and can include:
- metal oxides – these provide a wide colour range, but some are toxic to produce and use especially if based on mercury, lead, cadmium, or chromium
- synthetic organic pigments – these are less toxic to produce and use but may still be derived from petrochemical by-products such as phenols, benzene, toluene and xylene, all of which can be harmful to health
- naturally occurring earth pigments that include iron oxides
- plant-based pigments.
Binders and other additives
Binders include resins, oils and acrylic emulsions. Synthetic resins are usually part of both acrylic and oil-based paints. Acrylic paints have resins suspended in water, while oil-based paints have resins suspended in the solvent, mineral turpentine, which evaporates as the paint dries.
When buying paint, check for the following chemicals:
- epoxy – products using epoxy usually need solvents (like xylene and toluene) and chemical additives to form durable coatings and adhesives. Two-part epoxy systems can emit high levels of VOCs as they cure
- alkyd – this is a polyester or modified linseed oil system used for enamel paint and can cause skin or eye irritation
- polyurethane – this is produced by reaction with isocyanates and benzenes, which can cause respiratory and skin conditions. Polyurethane must be handled very carefully, and may emit VOCs during and after application.
Consider wall coverings made from inert and often recycled materials such as polyester, and plant fibres. Textile-based wall coverings are generally more breathable and less toxic than those based on PVC. Check the VOC levels of the additives and adhesives used to install wall coverings – they can be high.
The first thing to check before buying painting and decorating products is an ingredient list. Many paints and oils labelled as 'natural' fully declare all the product ingredients – including any references to aromatic compounds (ie compounds that contain or are based on benzene) that some people may find irritating.
If the ingredients are not declared, look for paints and products endorsed by independent schemes such as Environmental Choice New Zealand
A wide range of painting and decorating products is manufactured in New Zealand to suit New Zealand conditions, especially ultraviolet light durability. Natural paints and finishes can either be imported finished products, or imported ingredients that are on-processed locally.
To protect human health and the environment, support product suppliers using endorsed environmental management systems or who are making an effort to reduce the environmental and health impacts of their manufacturing.
Sustainability and life-cycle
Manufacture of paints, finishes and wall coverings generally involves a range of chemicals, solvents and raw materials from a variety of sources, and with toxicity levels ranging from high to zero.
If the material you are considering has low or no levels of toxicity, or toxic compounds, it will have less impact on the environment than ones that do.
If you can, source natural products from locally grown, renewable, sustainably managed or recycled raw materials. Ask your supplier for details if you aren’t sure of the product’s origins.
Efficiency and functionality
Paints and finishes
Durability and maintenance properties are important when choosing the best paints and finishes. Coatings that last longer tend to have lower environmental footprint over the life of the house – and you won't need to repaint as often. You may want to use different products in different parts of the house to suit different purposes. What you choose for the exterior may be decided by the type of surface you are painting, previous finishes, the climate and the required durability.
Many solvent-based and acrylic products were developed for their durability for a range of conditions, and ease of maintenance – especially when exposed to weather. However, natural products are often based on traditional formulations that have worked for decades, but may require more regular recoating.
Many natural paints provide good durability for inside use, as well as being more breathable and able to absorb moisture. Acrylic paints are durable, and can be easier to wash. Try samples to check the texture of the paint, as well as the colour – different ingredients provide a variety of surface finishes.
Using natural oils rather than polyurethane protects timber while allowing it to breathe, although some natural products still contain VOCs. Absorbing the oil reduces water penetration and helps protect from ultraviolet light. There can be trade-offs with finishes between durability, emissions, ease of use and time between recoats – it will depend on the surface. Where water or oil-based stains are used on exterior timber, they generally require re-application every three to five years to maintain their appearance. Check the manufacturer’s specifications.
If two products have similar durability properties, choose the one with the lowest VOC and the most information on its components.
These are popular for their durability and ease of use especially in high moisture and high ultraviolet environments. They also have a range of textures and effects including products designed for painting.
Recyclability, reuse and waste minimisation
Some regions have paint collection and recycling schemes for old and leftover paint, and may have recycled paints available. Container recycling should be possible through metals or plastics recycling, especially for environmentally labelled products. Some paint suppliers run programmes where unwanted paint is reused and the cans recycled. Where possible, keep or give away unused paint – don't throw it away.
Waste minimisation and disposal
To minimise waste, only buy as much as you need. Natural paints and finishes will eventually biodegrade on disposal, but all products should be disposed of carefully. Never tip paint or solvents down a stormwater drain or gulley trap. It can contaminate waterways or sewers.
If you have a reasonable quantity of leftover paint, you could ask around to see if family, friends or neighbours have a use for it. If not, or you only have a small amount left, several paint manufacturers will take back and dispose of or even recycle left over paint made by their company.
Paint recovery programmes on the Ministry for the Environment’s website has more information.
When painting, pour out small quantities into a disposable container or a lined roller tray (you can use plastic shopping bags for this). If you need to leave it for a short period, put a layer of cling film over the top to prevent a skin forming, and wrap your brush and roller with cling film and put them in a dark, cool place. If the paint has started to separate by the time you get back, give it a stir before continuing.
When you’ve finished painting, Ieave the excess paint to dry in a secure place, away from pets and children. Once it has dried, dispose of the whole container in the rubbish.
If you are leaving brushes or rollers overnight, put them into a container of water in a secure place and sponge off the excess water with paper towels or clean rags the next day before continuing.
When cleaning brushes and rollers, try to wash them over grass, which is a natural filter, or use the two-bucket cleaning method.
DIY painting on the Clean Waterways website has a brochure with instructions on the two-bucket cleaning method, and other tips for handling paint waste.
Leftover wall coverings made with vinyl, latex or other synthetic material will be difficult to recycle. However, it can come in handy for lining shelves and drawers, and you may be able to use it as a decorative finish on upcycled furniture.