Question 1

Do I always need primer before painting?

Accepted Answer

Not always. New drywall, bare wood, stain-prone surfaces (nicotine, water stains), and colour changes from dark to light all benefit from primer. Previously painted surfaces in good condition may need only a light sand and topcoat.

Question 2

What is the difference between primer and undercoat?

Accepted Answer

Primer bonds to the substrate and seals porosity. Undercoat builds up an opaque base colour, especially when switching from dark to light. Some products combine both functions.

Question 3

How does surface texture affect coverage?

Accepted Answer

Rough, porous, or textured surfaces (bare brick, rough plaster) absorb much more paint — coverage can drop to 6–8 m²/L. Smooth non-porous surfaces achieve the maximum advertised coverage.

Question 4

Can I skip primer and apply two coats of topcoat instead?

Accepted Answer

It is possible but usually more expensive (topcoat costs more than primer) and less effective on porous or stained surfaces. Primer also improves topcoat adhesion and durability.

Question 5

How long should primer dry before topcoating?

Accepted Answer

Water-based primers typically recoat in 1–2 hours; oil-based primers need 8–24 hours. Always follow the manufacturer's drying instructions — applying topcoat too soon can trap solvents and cause adhesion failure.

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