Priming New Drywall Guide
After you buy drywall, install it, and finish it, it’s time to put primer and paint on. If you try to paint over fresh drywall with regular paint, it will be difficult to achieve an even finish. The only way to ensure that you will get acceptable results is by using a primer.
A lot of people don’t like the idea of putting primer on because it seems like an extra step. However, it’s a necessary step that’s worthwhile. It’s also not as hard as you might think – it just takes some preparation.
Here are some things you need to know about priming drywall:
Prepare Before Priming
As mentioned above, you must prepare the area before priming. Double check to make sure all of the screw holes and seams are even. Clear dust off of all of the surfaces that are going to be painted. This is especially important if you have just sanded. Cover the floors and furniture in the room with plastic. If primer gets on anything, it’ll be even more difficult to remove than paint.
Using Drywall Primer-Sealer
Keep in mind that the mud used on the seams absorbs paint differently than other parts of the drywall. The difference in porosity can cause dull or blotchy areas under the paint. In order to prevent this problem, as well as sheen inconsistency, use a drywall primer-sealer.
Applying Stain-Blocking Primer
For areas with a high amount of moisture, such as a bathroom, kitchen or laundry room, you will want to apply a stain-blocking primer. This will help prevent blistering on the exterior walls, and peeling and mildew on the interior walls. There are vapor barrier primers available that allow you to seal the surface and reduce the passage of moisture through walls. In areas where mildew is a concern, you’ll need to use a stain-blocking primer to keep stains from seeping through the topcoat.
When To Use Oil-Based Primer?
When dealing with medium density fiberwood, use an oil-based primer UNLESS it already comes pre-primed. Whatever the case, do not use a water-based primer on MDF as it will soak into the surface and cause swelling. When priming, cover every surface, including the edges along the board.
High-Build Primer-Sealer To Fix Flaws
If your finished drywall has a few flaws here and there, like fine ridges or pockmarks, be sure to use a high-build primer-sealer, as it does a better job of filling in the uneven or rough spots and making the surface appear level. If your walls are perfectly smooth after finishing, however, you can just use a standard primer-sealer.
Amount of Primer Needed
A quality primer will usually go on in just one coat. However, it will take a fair amount to cover up the entire space, considering the absorptive qualities of new drywall and plaster. How much will you need? A gallon will probably be enough to cover around 300-square feet of raw drywall.
Don’t Paint Drywall Right After Priming
After applying the primer, you should paint the drywall within 24 hours. Many priming solutions are formulated to chemically and physically bond with the paint that is applied over them. This bond is only effective for a couple of days. You’ll want to make sure it’s dry enough however. Don’t start painting immediately after applying the primer.
If you’re unsure of what kind of primer to use, or when it should be applied, consult with your drywall supplier.