Paint is very rarely applied directly to a surface. Most surfaces need a primer coat in order for the paint to bond well. Different surfaces, wood, plaster, metal …etc. usually require different primers.
Most interior walls surfaces are Gyprock (plasterboard). This gyprock surface cannot be painted on without first applying primer. Without primer the paint soaks into the gyprock panels, giving a terrible result. And the plaster joints between the gyprock panels sow through the surface.
Primer gives Gyprock walls a neutral looking surface that bonds well to the final paint. The even texture from this primer prevents the joints in the wall from showing through.
Metal is often tricky to paint as many chemical will not bind to the surface. This is especially true of aluminium. Primers for metal will etch into the metal surface, providing a slightly rough texture that bond with paint. These primers often have reasonably good rust proofing qualities.
A different type of primer is used for wood. This primer will both fill in the grain of the wood and prevent the final paint from soaking in.
The paint used on gyprock can be used on wood if both surfaces have the right primer. But it is more common to paint woodwork a different colour or to stain the surface.
Some wood paints are designed show the grain of the wood through the final finish, and are to be used without primer. These are uncommon.
Masonry work like pipes will require masonry primer that will bond to the smooth surface.
These do exist, but for several reasons they have never proved popular. For one thing they are rather pricy. It is cheaper to buy an ordinary primer and a good quality paint. Another problem is that these paints often need two coats, which takes the same amount of time as a primer with a topcoat. Finally, the paints with built in primer are not available in all colours and finishes, so you may not find the colour that you want.
Good quality paint over a decent primer offers a lot of décor possibilities.
Talk to us about the décor and colour scheme for your home or office.