Paint Priming

What is a paint primer?

Paint primer also known as an undercoat is painted onto the surface before the topcoat. It provides strong adhesion for the surface and the paint. The primer in between provides paint durability and surface protection. The primer also blocks the smell or stain coming out of surfaces.

How is primer different from paint?

The basic difference between primers and paints is the chemical nomenclature. The primer contains resins providing bonding between paint and the surface while paint contains pigment to colour.

What types of primer are there?

Oil-based primer

Oil-based primers are handy for they work well with both latex and oil paints. It can be applied on many different surfaces. It is common for wood surfaces because of its best ability to seal the porous surface of the wood and provide a better surface to paint.

Oil-based primer goes good on metal materials. It prevents stains from appearing through the new paint on the material. Oil-based primers also prevent or slow down paint peeling blistering and cracking.

Their drawbacks are that it takes a long time to dry and releases a lot of harmful chemicals in the form of volatile organic compounds (VOCs) in long run.

Shellac Primer

This primer is comparatively less handy than the oil-based. They work well to seal in odours and smell from stained surfaces.  Any surface that requires sealing of smell or stain can be effectively done by using a shellac primer. It works on wood, plaster, plastic and metal.

Shellac primer is much quicker to dry than oil-based because they don’t penetrate the wood surface deeply. Due to their ability to soften under high temperatures, they can only be applied to certain areas on the surface in small patches, also known as “spot-priming”.

Latex-based Primer

Latex-based primers are water-based and are common for priming unfinished drywalls.  It is flexible and quick to dry. Latex-based primers also perform well with soft-wood, galvanized metal and concrete.

Unlike oil-based and shellac primers, latex-based primers don’t prevent the appearance and sealing of stained surfaces as effectively as the other two.  Since they come as low VOC primers, it makes them a healthier and safer choice to deal with.

When do we need a primer?

While priming may seem a waste of money, the prospect it brings up in the post painting is undeniable. So know when to prime your surface;

Changing the shade of the wall: It is difficult to change darker wall colours to a lighter tone. Priming will ease the changeover.

Painting latex-based paint over an oil-based: Primer will help you gain a better adhesion between the two different paint based chemicals.

Painting over metal or plastic: Painting over metal or plastic surfaces is frustrating. A primer will provide a strong base for the paint and also protect against rust.

Painting a new wall: New drywall and wood will need priming before painting. Wood is very porous and will absorb more topcoats if a primer is not applied.

Unattractive wall: Stains and damaged walls can be covered both in appearance and smell by primers.

You don’t prime when:

The walls are in good condition without any significant stains or damage.

The new paint matches the old Paint colour

How long does primer need to dry?

Most primers will need a minimum of 30 minutes to an hour to dry before another coat can be applied on top. However, you should not begin the second coat until the primer has completely dried. So, the crux here for professional results is to wait for the primer to dry thoroughly.

How many coats of primer should you do?

Primers don’t always cover the surface completely. Two coats of primer may be needed when changing from one colour to another. It is a good idea to tint the primer to the colour of the new paint.

Normal for any drywall one coat of primer is enough for better paint results.