What happens if you don't prime bare wood is not pretty. Similar to new drywall, raw wood soaks up paint like a sponge. As a result, your surface will look blotchy since pores in the woodwork unevenly absorb the paint. More importantly, the painted wood will likely peel in two or three years without primer.
Unpainted wood and drywall can pose huge adherence problems for coatings without primer. With fresh drywall, the substrate actually absorbs a coating really well, like a sponge. However, because it absorbs so well, without a primer coat, you'll experience uneven coverage, especially along drywall seams.
Use primer when drastically changing a color
There is no need to prime if you are applying a slightly different color, but anytime you are making a big change, it is a good idea. The last thing you want is to go through the work of painting only to see the old color showing through.
Painted Wood
If you are planning on repainting wood that is in good condition, you may not even need to apply primer. However, if the paint is chipping and cracked, you should try to scrap off most of the old paint and apply an oil-based primer.
Painting Bare Wood
As well as providing the best possible adhesion, priming evens up the variable absorption, giving you a uniform surface to ensure consistent performance from the finishing system (undercoat/finish).
Options That Require No Prep Work
Milk paint, which you can purchase as a powder or premixed, or even whip it up yourself at home, is a nontoxic and biodegradable paint option that's great for use on wood furniture—and if you mix it with an equal part of bonding agent, you don't need to sand the piece before beginning.
Apply a primer
When applying acrylic paint on wood without primer, your project is unlikely to turn out in the desired way. Applying a thin layer of wood primer will help seal the wood, allowing the acrylic paint to apply easier. When a layer of primer is applied, lighter colours will also appear more vibrant.
Mineral Paint: Similar to chalk paint, but often more expensive. Top coat recommended. Milk Paint with bonding agent: Also does not require sanding or priming, however the colors are limited and you have to mix your paint/bonding agent well.
MINERAL PAINT (My Favorite Option)
With Mineral paint you don't need to prime anything beforehand. It'll adhere to just about anything.
Fusion Mineral Paint is a decorative furniture finishing paint formulated with a built in top coat in over 50 colors. It's known for its matte like finish similar to chalk paint or milk paint without the mixing, priming or top coat!
On new drywall, you will use 3 coats of the finish material instead of a primer coat plus 2 coats of finish. Most projects where you're going over a previously-painted surface do not require the use of a primer.
There are a few things to consider when deciding whether or not you need to use a primer before painting: the type of paint you are using, the surface you are painting, and your skill level. If you are using paint that is designed for indoor use, like latex or oil-based paints, then you don't need to use a primer.
If you're painting wood without a stain or finish, use a latex or an oil-based primer for the best results. Don't over or under apply the primer: You should aim to apply two coats of primer to your wood's surface. Brush the primer on, and allow the first coat to dry completely before adding the second coat.
Face primers prep skin ready for smooth foundation application. Think of your skin and makeup like canvas and paint. You can apply paint directly to your canvas/skin, but priming it first increases the longevity of your work and makes the surface easier to work on, so you won't have to use as much paint aka foundation.
In general, the only time a primer is not needed is if you're re-painting a surface that's in good condition. Your neighborhood Sherwin-Williams paint expert can provide additional advice about selecting and applying the right primer for your project.
This also causes paint to dry more slowly, making your paint job more difficult, and can even lead to just as uneven a finish as if you hadn't used primer at all. One to three coats of primer is perfect for any paint job in your home.
Because it soaks in similar to a stain, Milk Paint is THE best paint to use on a raw wood surface with no existing finish.
You may or may not need more than one coat, depending on the paint type you choose. If so, it's vital to let the first coat dry properly first or you'll make an awful mess of it. As a general rule, two coats deliver a better sheen and a deeper, fuller finish than one.
Despite what you may have heard — or maybe your own last attempt — you absolutely can paint over stain beautifully and durably. The key to getting a professional result is recognizing the projects that will require more work, then choosing a paint that accommodates both your aesthetic and your patience.
The best rule to adhere to is to apply at least two coats of sealer directly onto the raw wood. This will protect the wood and create a barrier. Then apply primer to enhance adhesion, return tooth to the surface, and whiten the surface for optimising paint colours you plan to apply over it.
If you paint bare wood such as cedar siding before priming, the paint can lift or peel off because it has nothing to adhere to. This will result in disaster, the paint will chip or flake off and will not stand the test of time. There are oils and tannins in the wood that can bleed through.
Whether you are using lumber fresh off the market or refreshing an old piece of furniture, it is important to sand it first to remove any surface irregularities and the old paint. The goal is to prepare the wood to receive the new, fresh paint coat.
Types of Paint to Use on Unfinished Wood Crafts
Latex paints are ideal if you are looking for general coverage with a fast-drying, durable finish. They work well on both interior and exterior surfaces. Acrylic paint for wood crafts have the same qualities as latex paints and can also be used on unfinished wood crafts.