Primer : Is it necessary to apply it before Painting?

Painting any surface basically serves two purposes. It enhances the beauty of walls/ structure and also protects the surfaces of the structure. Before painting any surfaces, the application of primer is recommended. Some question arise, like – Why primer is required? Can’t we do away with primer by applying one more coat of paint? For a layman, the difference between the two is not easily understood as both look similar.

Before painting any structure, you should know the difference between primer and paint. Paint and Primer both are different products, though they look like same. They have a different purpose, function and constituents. We would first explain the primary difference between primer and paint.

Difference Between Primer and Paint


Primer is paint but without pigments, it primarily consists of resins. Primers are designed so that they create a bond with the sub surface and also with paint, to create a uniform surface which is suitable to receive the paint.

Function of Primer

Primer penetrates in the porous surface and seals the surface to ensure better coating and adhesion. It also hides imperfections and provides an even, smooth, and stable foundation for the paint. It is a problem solver providing good coverage.


Almost the major constituents of paint remain same as a primer, plus paints contain pigments, which provides the colour. Paints contain different types of additives than primers. These additives perform a different function like providing bond and adhesion, quick drying, durability, etc.

Function of paint

Paints add colour and shininess to the surface. They make the surface finished and provide protection. Pigments in paints also help in hiding the surfaces. There are many constituents added in the paint so that it dries quickly and it gives durability, i.e. life to the paint.

If the paint is applied to an unprimed surface, it may crack, peel off within few months. For paint to last long, priming the surface with the right primer is important.

Now, We jump into a commonly asked question i.e. Is it necessary to apply Primer before painting?

The primer as the name suggests, is the primary layer that is ready to receive paint. It is nothing but paint without pigment. It improves the adhesion of paint and thereby increases durability and life of paint film. Apart from this there are other uses of primer:

Primer before paint is like the base of your paint job and can be used on wood, plastered wall, concrete, etc. Applying primer coat over new surfaces reduces the amount of paint being absorbed by the basic surface. The primer will help you in hiding joints and other small defects, when it is applied to surfaces. Basically it is paint without pigment, it serves all the functions of the paint at a lower cost, as it is the pigment which increases the cost of paint. If primer coat is not applied, you might have to apply one more coat of paint, which of course will increase the cost. It increases covering capacity of the paint and thus decreases the overall cost of painting.

If suitably applied, primer will enhance the life of the paint, and also improve the appearance. Therefore primer before paint is absolutely necessary.

Some tips for Primer Application

  1. It is essential that the primer should only be applied to dry and clean surfaces. Before the application of primer coat, the surfaces are smoothened by sand paper and dust is removed.
  2. After the primer coat application, to ensure proper drying of the primer, the surface should be painted after a few days.
  3. The surfaces that have deteriorated should be cleaned properly before the application of primer.

And follow the instructions as per manufacturer’s specification.

Proper interior and exterior surface preparations combined with primer will build an effective barrier against stains and moisture and promote full adhesion of the paint. Primer is thus very useful as it reduces the cost of overall painting and also increase the appearance and life of the paint.