It is almost always the case with paint that you get what you pay for. Better quality paints have more solids in them giving better paint thickness and performance – and they generally cost more.

Other than quality, selection should be made according to:

  • whether you want to use solvent- or water-based paint
  • what the material is that you are painting
  • whether interior or exterior paint is required.

You can also refer to the standard AS/NZS 2311:2017 Guide to the painting of buildings, which has guidance on “products and procedures for the painting of buildings for general domestic, commercial and industrial use.

Water-based and oil-based paints

Paints on the market today fall into two broad categories:

  • water-based formulations (including acrylics, co-polymers and PVAs)
  • volatile solvent-based (oil-based) formulations (including alkyds, oil-modified alkyds and urethanes).

Identify existing coatings so that the new paint is compatible with the old.

To determine whether an existing paint finish is water-based or solvent-based:

  • Soak a cotton ball in rubbing alcohol (isopropyl or ethyl alcohol), an acetone-based nail polish remover or lacquer thinner.
  • Rub it over a small, inconspicuous section of wall.
  • If paint comes off, it is water-based; if unaffected, it is a solvent-based paint.

Oil-based paint should generally not be applied over water-based paint or on certain cladding systems such as cement plaster-based textures.

In the past, solvent-borne paints were the only option for contact surfaces such as those on windows, doors and cupboards, because acrylic paints tend to have poor block resistance - when two such painted surfaces come into contact, they can sometimes stick together. Solvent-borne paints, which have good block resistance, are unlikely to stick. Other surfaces that were previously considered necessary to paint with enamel paint were the surfaces in high moisture environments such as kitchens, bathrooms and laundries.

Since the development of water-based enamels, that provide similar durable and glossy finishes to solvent-based enamels, acrylic paints are also able to be used in wet areas and for joinery. They have the same advantages as other acrylic paints including being quick drying, having lower odour and being able to clean up in water.  

Advantages and disadvantages of acrylic and alkyd paints

Paint type



acrylic (water-based)

easy to apply

more shrinkage than solvent borne paint

short drying time (usually about 1 hour)

may dry too quickly in warm conditions

clean up in water

tends to ‘skin’ in the can as it begins to dry out

better fade resistance than solvent-based paint

cannot be removed as easily by hot air gun stripping

mould/mildew resistant formulations available

longer curing time than solvent-based paint

does not have a strong odour which means fewer VOCs (volatile organic compounds)




is available as enamel paint


has poor block resistance – will stick when two painted surfaces are in contact – except for water-based enamel paint that has been formulated for painting doors and windows


alkyd (solvent-based) paint

has a harder finish – more scuff resistant and easier to wash

increased brittleness, cracking and peeling with age

goes on more smoothly and has a smoother finish than acrylic paint

clean up requires paint thinner or other solvent

provides better (thicker) cover in a single coat than acrylic paint to cover wall imperfections or staining more effectively

thicker finish gives less coverage

longer drying time is better for use in warm conditions

longer drying time than for acrylic

better chemical resistance than acrylic paint

more likely to have higher VOC levels

has good block resistance – is unlikely stick when two painted surfaces are in contact


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Sealers, undercoats and top coats

The type and sequence of coats of paint are:

  • for new or bare timber: sealer coat, optional undercoat, finish coat 1, finish coat 2
  • for plasterboard, fibrous plaster, softboard, hardboard, fibre-cement, particleboard: sealer coat (use a solvent-borne sealer in wet areas), finish coat 1, finish coat 2.

A sealer coat is typically the first paint coating applied to bare internal surfaces, and the names primer and sealer are often interchanged. Sealer coats:

  • provide a base for adhesion to the substrate for the paint system
  • provide protection to the substrate
  • prevent stain bleeding such as from ball-point or marker pens or ink in wallpapers that are painted over, through subsequent coats of paint.
  • help to seal porous surfaces to prevent subsequent coats of paint from soaking into the substrate
  • even out porosity such as on plasterboard where plastered joints absorb less paint that the paper finish
  • seal over waxes or oils in the substrate so that paint can be applied to the surface.

The sealer must be compatible with the existing paint where the surface is being repaired and repainted – an acrylic sealer should be used if the existing paint is acrylic. The correct application of a sealer must be made with a specific substrate.

Sealer use with specific substrates or previous finishes


Sealer coat to use

plasterboard, softboard (dry areas)

acrylic wallboard sealer

new/exposed timber


solvent-borne timber sealer – can be used with both solvent- borne and water-borne top coats

acrylic timber sealer – use only with acrylic top coats

fibrous plaster

solvent-borne sealer

wet  area plasterboard, hardboard

solvent-borne sealer

existing varnish

methylated spirits-based sealer

 As a general rule, solvent-based topcoats should be used over solvent-borne sealer coats, while acrylic topcoats may be applied over both solvent-borne and water-borne sealer coats.

Undercoat paint is no longer necessary in many circumstances, as newly formulated top coats no longer require them. An undercoat may be useful, however, if a painted surface is being changed from a dark to a light colour.

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Paint finish

One key selection option for top coats is the paint finish – gloss, satin or semi-gloss, or a matt finish. Both water-based and solvent-based paints are available in all finishes.

Gloss and satin finishes are easier to clean than matt finishes, making them more suitable for areas that are likely to require more frequent cleaning such as a kitchen or family room. Matt or low-sheen paints can be used for areas such as living rooms and bedrooms. A gloss finish will highlight defects or imperfections more than satin or matt finishes will. Ceiling paints are formulated to be low-sheen to mask surface imperfections, except in high-moisture areas such as kitchen and bathrooms where condensation may be a risk.

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