Do You Need to Sand Between Coats of Interior Paint?

When to Sand Between Coats of Paint

Understanding the interior painting basics is key to a perfect paint job. If you’re not familiar with professional home improvement projects, you’re probably unsure whether to sand between coats of paint.

Do You Need to Sand Between Coats of Paint?

The short answer is yes; you should sand between coats of paint. Here’s the thing. If you choose to skip the sanding step, you’ll end up with an awful paint job. Even so, avoid excessive sanding as it would also ruin your interior paint job.

Sanding is essential for the following reasons:

1. To eliminate roller build-up

You may have noticed that wall paint appears bumpy despite applying several coats of paint. The reason for this is roller build-up. The obvious sign is usually when a roller stops spreading as smoothly as it did before. Unfortunately, some end up dipping the roller into more paint which results in the build-up. Sanding is the best way to correct this painting mistake.

2. Sanding helps your paint stick

Sanding between coats is necessary if applying latex paint on top of oil-based paint. This is because oil-based paint creates a gliding surface, making it difficult for any color that goes over it to stick.

You’ll need to ascertain whether your paint is oil-based before sanding your interior walls. Start by washing a small section of the painted wall with soapy water. Then soak a piece of cotton in rubbing alcohol and wipe it across that area. You’ll know you’re dealing with latex paint if the paint transfers to the cotton ball. If it doesn’t come off, it’s oil-based, which means you must sand it before spreading the next coat.

Sanding is straightforward. Just wrap sandpaper, using a light touch, buff the wall to give it texture.

3. Get rid of texture

Adding texture to a wall is an easy way to jazz up your wall. However, over time you might want to revert to the flat wall look. With some light sanding, you can eliminate the texture for a smooth wall surface.

What If It’s Just Latex Paint Alone?

Should you sand between coats if it’s just latex paint alone? No, you shouldn’t. Sanding latex paint will chip off the entire color paint. While sanding helps to correct paint mistakes, it won’t get rid of paintbrush strokes.

The ideal solution for paintbrush marks is to strip the entire paint and paint afresh. Ensure you use a paint roller and pour some latex paint additive to prevent paint marks.

Now, while you shouldn’t sand between coats of latex paint for walls, you can’t miss this step when painting cabinets and trims. This is because sanding creates a glossy finishing. Don’t forget to wait until the paint is dry to the touch before sanding. Typically, the ideal drying temperatures lie in the 70 to 80 degrees Fahrenheit range.

We recommend a 120- or 150- grit or a medium-grit sanding sponge when sanding fresh paint. Coarser-grit sandpaper is ideal for already cured paint. So you’ll need to wait for at least one month for your color to harden if you intend to use coarse sandpaper.

How Long Should You Wait Before Sanding Between Coats of Paint?

Rushing your coats is one of the easiest ways to ruin your paint job. While today’s paints are quick-drying, you must give each coat time to cure to get that smooth finish. Three clear-cut time frames are available for your consideration when dealing with latex (water-based) and oil-based paint.

  • Drying time – Dry time refers to the time required for fresh paint to become dry to light
  • Recoat period – Recoat time is the time length you must wait before applying a second coat.
  • Cure time – Cure time refers to the time required for the paint to harden entirely and is even safe for washing.

All water-based paints have a shorter drying time compared to oil-based paints. The reason is simple. The water ingredient will evaporate, making the latex paint dry fast. In contrast, oil-based paints lack water, hence the longer drying time.

Besides that, every wall paint has binders. However, flat colors contain trace amounts, while the glossy types have the most binders in them. This means that the flatter a color sheen is, the quicker the drying time. In comparison, the more polished the paint is, the longer it will take to dry.

You’ll notice that both paints will be dry to touch after an hour or two. We recommend waiting about 24 hours before sanding your wall. Ensure to also check the instructions for a more clear-cut drying time frame.

As mentioned earlier, temperatures also influence the drying time. Ideally, the room should be humid and be at least 75 degrees Fahrenheit for latex paints. Oil-based paints require temperatures ranging between 50 and 90 degrees Fahrenheit. You should consider turning your fan on or opening the windows to quicken the process further.

What Sandpaper Grade is Ideal?

The sandpaper grit you use matters. Each size has a specific number, with the higher numbers signaling finer grits. For instance, 1000- grit is smooth, while 24- is a coarser grit type. Lower numbers are ideal for sanding wood and other rough surfaces with ease.

Fine grit sandpapers, i.e., high-numbered types, are perfect for smooth surfaces. The 120- and 150- are the ideal sandpaper grades for sanding between coats of interior paint.

Hand Sanding or Power Sanding, Which Is Better?

Typically, you’ll find two primary advantages that hand sanding has compared to power sanding.

  • Hand sanding before applying the final coat produces a better finish than a power sanding tool will. This is because a power tool leaves marks.
  • Hand sanding also lets you to delicately tune areas. This is primarily due to their flexibility which will enable you to sand along with architectural molding. In comparison, power sanding tools can not fit in tight spaces.

Dangers Associated with DIY Sanding

Latex paints consist of chemicals and solvents. One ingredient that’s of particular concern is crystalline silica. Inhaling this ingredient can lead to tuberous growths or lung scarring. More prolonged exposure could result in silicosis, which might progress to cancer.

You must always wear an air respirator, not a dust mask, as it does not filter crystalline silica. Another thing to keep in mind is that latex paint on older walls has lead and mercury, this combination of substances is also toxic. Let’s not forget that interior latex paint has formaldehyde which causes ENT irritation, nausea, and headaches.

Contact Tampa Bay Company For Interior Painting Services

An excellent paint job requires sanding between coats of paint. It also requires knowing the specific drying times, sandpaper grit, and ideal tools. Painting walls also carry significant health risks-which is why it’s best to hire professional painters in St. Pete.

The professional painting team at Tampa Bay Painting Company will have the right tools and protective equipment. In addition, we will save you from redoing a paint job, which is time-consuming and wasteful. Tampa Bay Painting is a reputable company offering interior and exterior painting services in St. Petersburg. Let our team eliminate all the guesswork. Call us today at (727) 800-5988 for unmatched painting services in Tampa Bay.