08-27-2013 07:53 PM
You need to prime if it's bare drywall or wood. If you're going from a really dark color to a light color there's some sense in priming because primer is cheaper than paint. If there's paint already on the walls just clean them and patch any dings, nail holes etc. with a little spackle.
Invest in good tools for painting. A good brush costs at least $10 and don't come in sets of three for $4.99. Don't buy cheap roller covers. Don't put down plastic, use canvas drop clothes (they tend to stay in place instead of bunching up under your feet).
08-28-2013 12:24 AM
Primer performs one of four functions:
- It seals bare or very dry surfaces, such as new drywall or over "contractor's" grade paint
- It adheres to very slick surfaces
- It seals in stains
- It helps in making a drastic color change
If your room doesn't fall into one of these categories, you probably don't need a dedicated primer. However, one of the paint and primer in one paints,such as Behr Ultra or Glidden Duo is still a good idea. Behr Premium Plus is also self-priming, however, it does not have Ultra's stain killing attribute.
Often when making a drastic color change from dark to light, using the paint itself to "prime" the wall works at least as well as a dedicated primer. Obviously, the first coat will be of the actual color. It also makes buying and using two different products ( paint and separate primer) unneccessary. To this extent, it is cost effective.
Hope this has helped.