Does “Paint and Primer in One” actually work?

Homeowners and DIY enthusiasts have almost certainly heard their favorite paint company advertise a product that eliminates the need to prime. “Paint and primer in one? My lucky day!”  This sounds especially tempting for rooms that are less central to the home, or likely to be changed again down the road, such as kids’ rooms.

What’s the Hype vs. the Reality?

Over the past decade, almost every paint manufacturer has designed a product that appeals to the DIY market.  Behr started the trend, and soon others like Sherwin Williams, Benjamin Moore and PPG followed suit.  In many cases, they just updated their existing paint product labels, adding “paint and primer in one”, “self-priming paint”, or similar language. It’s a clever move, since most homeowners want to save steps, save money, and above all, keep it simple.  Given the choice between buying a can of primer PLUS a can of paint, or just “paint and primer in one”, who wouldn’t choose the multi-use product?

The issue is, do these products work?  What are the pros and cons? How much do they save you time, and how much is just clever marketing?

 

Most “paint and primer in one” products don’t contain any primer

What makes a paint and primer in one?  Usually just a higher concentration of “solids”, which are the materials in a paint that provide what painters call coverage or “hiding ability”.  So, a “self-priming paint” is just a thicker paint that is more likely to hide the underlying color that you’re painting over.

Well, isn’t that what you need to do anyway??  Maybe.

A Lesson in Primers

Let’s tackle reason number one in more detail.  What does “prepping the surface” mean?  It depends on your surface!

 

Different Types of Surfaces that Need a Separate Primer

Raw wood.

This needs either an oil-based or special latex-based primer to seal it, so it doesn’t swell from the wet paint you’re going to put on it.  If you have an entire kitchen of brand-new cabinetry, this is not something you should tackle yourself.  But if you’ve just replaced a baseboard or two in your home, and you didn’t get the pre-primed type from the hardware store, then you can prime it before painting.

Raw sheetrock, drywall, or joint compound.

These are the materials used to add a new wall, apply fresh texture, or patch over a hole in your wall.  They are porous and extremely chalky, and need to be sealed with a primer that matches their pH level, before top-coating with paint.  Otherwise, you could be wasting time, money and energy applying multiple coats of paint on your porous surface before you finally achieve a nice, solid coat of color that won’t come off at the slightest touch.

Slick, glossy surfaces like tile, glass, or brand-new cabinets or furniture.

Hard, smooth surfaces like these require a bonding primer, which is specially formulated to stick to the surface.   Otherwise you can scrape your nice pretty paint off later with your fingernail.  We’ve seen it happen, many times!

Walls that are stained from a water leak, cigarette smoke, etc.

You need a “stain-blocking” primer to seal out water stains, crayon marks, smoke stains, and such.  And if you’re dealing with odors, you’ll need a shellac-based primer (not the funnest stuff to work with, and be sure to wear a respirator!).  Regular “paint and primer in one” products don’t have those kinds of stain blockers, so those stains would eventually seep to the surface of your freshly painted walls.  It might seem like you’ve covered any stains when you first roll on your paint and primer in one, but the chemistry of the underlying stain often reacts with the paint and will reappear like magic (the bad kind) after several months.

Stain blockers (a kind of primer) are also needed if you have woodwork with a high tannin content, like pine, which has lots of natural oils that can seep through the knots in its grain.  Those tannins can “bleed through” any existing paint if it wasn’t primed properly the first time, showing up as spots that need a stain-blocking primer to fully cover.

Metal surfaces, like patio furniture or guard rails.

These need a “direct-to-metal” primer that’ll stick and will prevent rust.

Oil-painted surfaces, like most older woodwork (baseboards, doors, windowsills) in many homes.

If you’re going to paint over these, you probably want to use a water-based latex or acrylic paint, so that you don’t have to deal with smelly oil paints and the nasty paint thinners that you’ll need to clean up when done.  But water-based paints don’t stick to oil-based surfaces.  You need an oil-based primer first.  (It has a mild smell, but not so bad as using several coats of oil paint.  Plus it dries quickly.)

Older homes often have oil-based trim on the exterior, so these will need to be primed accordingly.

 

When should you use paint and primer in one?

Walls that were already painted with latex paint, and are a drastically different color from what the new color will be.

This is Scenario 2 above, and the only case where a thick, self-priming paint might work.  A thicker paint will cover better, after all.  And your walls were presumably already primed before they were painted the first time.  So the priming has been done for you.

You can even use it to go from a light color to a darker color.  It can’t hurt.

By the way, you’re probably not going to save any money this way.  These paints are pricier than just primer + paint, and you may still need extra coats.  Again, it’s a gamble!

Just make sure the entire surface was primed and painted already.  If you’re painting over a bedroom where you just patched a hole with fresh drywall and joint compound, please use a primer first, because nothing will truly bond to that surface unless it’s primed.  Ever stuck some tape to a wall, maybe to put up a poster or your child’s artwork, only to have it peel the paint away when you remove the tape?  I’ve seen even the most delicate tape remove paint from walls that have not been primed, more often than I can count.

To recap:

When should you use paint and primer in one?   Or rather, when is self-priming paint not going to work?

You cannot replace the need to use a separate primer if you are dealing with raw surfaces such as raw wood, bare drywall, metal, or cement, or with glossy surfaces such as new cabinets or oil-based woodwork. Primers are made to seal raw surfaces, they generally have more adhesive qualities and are designed with a flat “sheen” (no shininess or glossiness), so that your color coat of paint will stick to it well. 

It is appropriate to use a “self-priming” paint when you are changing colors over previously primed or painted latex-based walls.  After all, the actual benefit of this product is its coverage abilities. It’s a “high solid content” paint (it’s thicker, basically) that has the ability to “self prime” over contrasting colors or big color changes.

Remember, priming and painting are two separate processes.

You can’t skip priming and still achieve professional results. These steps shouldn’t be melded together to try and save time, because fixing the problems that arise from not priming are harder to resolve than the time it takes to just prime and paint in the first place. 

Save the self-priming paint for those times when you’re repainting a wall in a new, dramatically different color.  In that situation, paint and primer in one can save you time and money.