Oil-based will seal the wood better and block any tannin stains that might bleed out. Oil-based is also ideal if blocking smoke and water stains as well as unwanted odors. Choose water-based if priming indoors where ventilation may be poor and in spaces sensitive to strong odors.
Which one should you choose? Oil-based primer is commonly used for its stain and moisture blocking qualities. On the other hand, people like water-based primer because it has fewer VOCs, dries quickly, and is much easier to clean up. You can't apply an oil-based primer under a water-based paint, and vice versa.
Oil-based primers are ideal for interior and exterior unfinished or bare wood because they seal the porous surface of wood, enabling the coat of paint to better cover the surface. They stop tannins, released from woods, such as cedar or redwood, from bleeding through the surface of the paint.
Because there are light, moderate, and severe stains, Kilz has formulated multiple primers to ensure each type of stain can be covered easily and successfully. For light to moderate stains, it's recommend to use Kilz Premium. For more severe stains, try using Kilz Max.
KILZ® ORIGINAL Oil-Based Primer is a powerful stainblocking formula that blocks most heavy interior stains including water, smoke, tannin, ink, pencil, felt marker, grease, and also seals pet, food and smoke odors.
A question we get asked often is, “Can you paint latex over oil?" The answer is, “yes”. But you can't treat it like latex or water-based surfaces.
Kilz Brand paint produces several types of oil-based primers that are formulated for a variety of applications, including interior and exterior use. Their manufacturer-recommended cure times range from 15 minutes to one hour; however, there are several factors that affect cure times.
“Does Kilz kill mold?” Despite the brand name “Kilz” sounding like it would kill mold, Kilz does not kill mold, but does proactively prevent it.
In our Zinsser vs Kilz primer comparison, Zinsser came on top in terms of odor, bleed-through prevention, and adhesion.
Oil-based paints dry to a hard shell. This means that they are suitable for baseboards, shelves, and other areas that might experience wear and abrasion. Water-based paints, on the other hand, are prone to rubbing off when abraded.
Oil-based paint releases a higher number of Volatile organic compounds (VOCs). This means that oil-based primer isn't the first choice for indoor use, as the VOCs can be harmful when inhale routinely.
You will want to use 2-3 coats of primer to ensure there is a good bond between the new paint and the wall, and also to cover up any previous colors, especially if they are red, orange, or a strange outdated color. In short, you will typically need 2 coats of primer for most painting projects.
When you drag your brush across oil-based primer that is drying, the brush will leave marks and rough up your smooth surface. The only fix will be to wait until it is completely dry and then use a sanding sponge aggressively to make the surface smooth again.
Differences Between Oil & Water-based Primers
Applying oil-based primer is recommended for wood surfaces as it helps seal the grains, thereby preventing paint from bubbling as a result of water damage.
KILZ 2 All-Purpose Interior/Exterior Multi-purpose Water-based Wall and Ceiling Primer is a great all-purpose primer at a good price. It can be used indoors or out, and it works especially well on previously painted surfaces; besides drywall, it's effective when applied to interior or exterior wood and masonry.
CAN YOU USE OIL PAINT OVER WATER-BASED PAINT? Yes. In fact, this option works so much better than the opposite: painting with a water-based paint over an oil-based layer. This is quite common when you use primers to prepare a wall, cabinet doors, or trim for the final paint layer.
Temperatures above 90°F may affect the application such as drying too fast. Avoid painting in direct sun. Shelf life under normal conditions is two years unopened.
Kilz is inexpensive, but it is only meant to assist in painting, not take over the job completely. Kilz, in turn, will help you save money and time, but you must use both kilz and ceiling paint to have a good result.
Dries to the touch in 30 minutes. Can be recoated or topcoated in one hour with latex or oil-based paint. Application at lower temperatures, in high humidity or in poorly ventilated areas will affect dry time.
White vinegar containing 5% acidity will also work just fine. If you don't already have some at home, white vinegar can be inexpensively purchased at most grocery stores. Vinegar can be used to kill mold on both nonporous surfaces and porous surfaces.
Zinsser Mold Killing Primer is a water-based EPA registered fungicidal protective coating that can be used to paint over and kill all existing mold, mildew, moss, fungi, odor causing bacteria and any other fungal organisms.
KILZ® MOLD & MILDEW† Aerosol Primer is a water-based primer-sealer-stainblocker that is specially designed for residential surfaces in high humidity, moisture and temperature environments such as kitchens, bathrooms, powder rooms and laundry rooms.
I used a small ½-inch thick roller nap to apply KILZ 3® PREMIUM Primer. After allowing it to dry for only an hour, I lightly sanded all surfaces again and then was able to apply a second coat using the same size roller nap.
The highest quality bonding primers will often state 'no sanding is necessary' and will adhere to almost any shiny surface, such as glass, metal, tile etc. Primers like Kilz, Fuse, and Zinnser are good for bonding very strongly. Primers can be costly, but if they are of good quality there will be no need for sanding.
Sanding your door well, before priming and painting, is the right way to do it. Sanding will create a smooth surface that will help your paint to look great. When sanding, do a first pass with 100-150 grit sandpaper then finish with a second pass of 180-220 grit sandpaper.