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What is the purpose of paint primer?
Primers are a base coat that seals surfaces and allows the topcoat of paint to go on more smoothly and evenly. Primers can help finicky or light colours of paint look their best on any surface without bleed through or discolouration.
How do I choose a paint primer?
You'll want to use interior primer for indoor painting, exterior primer for outdoor painting, and spray primer for spray painting. A multi-purpose primer can be used indoors and outdoors and is a good choice if you've got a lot of painting to do.
Is there a difference in paint primers?
Most primers are suitable for wood and drywall, but some are specifically designed for metal surfaces and will protect against rust. Oil-based primers are better for outdoor painting since they seal better against moisture.