How Many Coats Of Paint? - Overland Park Exterior Painting


One question we are asked by Overland Park homeowners is “how many coats of paint do you do?” The answer isn’t a straight 1 or 2, and we see a lot of mis-information both on the internet and from other painters who say they are doing 2 coats of paint, but in our professional opinion are not. Let’s investigate.

Are 2 coats better than 1

It depends… The exterior painting product we use most often is Sherwin Williams SuperPaint. In this product, yes, 2 coats are going to be more durable and last longer than 1 coat. Building up the thickness of the applied paint helps resist breakdown of the paint material and fading. 2 coats of paint costs more in additional material and labor cost (we’ll discuss more on the labor side of things later).

Another option we offer for exterior paint is Sherwin Williams Emerald. With Emerald, Sherwin Williams offers their Lifetime Limited Warranty for 1 coat (applied correctly to a good surface). Emerald is more expensive per gallon than SuperPaint, but in our experience the additional material cost is less expensive than applying 2 coats of SuperPaint and you reach the same end goal.

For customers who request a 2 coat paint job, we recommend they look at Emerald.

A true 2 coat paint job

Take a look at the below language on the spec sheet for the most popular exterior paint we use in Kansas City and Overland Park:

Sherwin Williams SuperPaint spec sheet language

The two things to notice on this spec sheet are:

  1. Mil Thickness
  2. Recoat time

Mil thickness

Mil thickness is the thickness of the paint film that is applied to the surface being painted. Sherwin says this should be at minimum 4 mils wet.

Application method matters here. We use expensive, top-of-the-line airless spray equipment to apply our paint. With an airless sprayer, we can apply the exterior coating over the 4 mil thickness value in 1 pass. If we’re applying the coating via a brush and roller, in our experience it will require 2 coatings to meet the mil thickness spec Sherwin Williams sets. I’ve painted many surfaces with sprayers and with brushes, and I’ve never been able to apply paint as uniformly and at an an equivalent thickness with a roller or brush as I can with a sprayer.

If your Overland Park painter is telling you he’s doing 2 coats, ask him if he’s brushing & rolling or spraying the coating on. If he’s brushing/rolling, he’s likely going to need to do two coats. If he’s spraying the coating and he’s saying he’s doing 2 coats, you have followup questions to find out what he means and it’ll have to do with dry time.

Drying time

Notice that in the Sherwin Spec drying time @ 50% relative humidity (RH) when the temp is over 45 degrees is a minimum of 4 hours. To get a true 2 coat paint project, the paint needs 4 hours to dry before it can get re-coated. If the humidity is higher, more time is required.

If any painter says they’re applying the coating via spray and doing 2 coats, then likely this means their sequence should look like:

  1. complete all their prep work
  2. spray the 1st coating
  3. let the home dry overnight (it takes 1 day to spray the base color of an average home)
  4. return the next day and spray the 2nd coating

This isn’t typical, and though we see lots of painting contractors saying they’re doing 2 coats, we don’t see them doing this. They aren’t allowing the surface to cure a minimum of 4 hours before recoating. In our opinion that’s misleading because what they’re doing isn’t a true 2 coat system.

As a homeowner if you request a 2 coat system from us, this is how we’d estimate it. It adds an extra 1 to 1 1/2 days to the labor on the project and the additional material for the 2nd coating.

The Spray and Backroll

Sometimes when we’re working with a porous or otherwise rough surface, we need to backroll the surface after we apply the paint with an airless sprayer. This is a 2 person job. One person delivers the paint material to the surface via the airless sprayer, and another person rolls the surface soon afterward to ensure the paint is pushed into the pores.

On occasion we talk to customers who say another painter called this a 2 coat paint job. Based on our discussion of dry time, we hope you understand why we believe that to be misleading and incorrect. In our opinion, spraying and backrolling is a 1 coat system. Unless the surface cures for a minimum of 4 hours and is sprayed and backrolled again.


Summary

This is how we look at coating systems. Because of our application method being predominately airless sprayer on exterior projects in Overland Park and Kansas City, we don’t go by the number of coats, but by the specified mil thickness of the manufacturer.

When we’re spraying an exterior with SuperPaint, we coat the surface at a minimum of 4 mils thickness 1 time. If you’d like 2 coats, we can cost out doing 2 coats of SuperPaint vs. 1 coat of Emerald. You’ll get the same manufacturer guarantee from Sherwin Williams and the same warranty from us and the Emerald will be less expensive for you.

Surfaces that we brush/roll, we’ll apply 2 coats on.

Ask any painting company you’re taking a bid from how they’re applying their paint if they’re telling you they’re doing 2 coats. If they’re applying with an airless sprayer and aren’t going to let it sit overnight and spray the whole house again the next day, in our opinion they either don’t understand the specs or are misleading.

We hope you find this helpful, and as always, our estimates are free and we’re happy to discuss coating systems and technical aspects at length!