Satin vs. Semi-Gloss Polyurethane (Which One You Need?)

Polyurethane finish comes in satin, matte, semi-gloss, and high-gloss sheens. Of these four sheens, the most common are satin and semi-gloss. Both finishes are easy to achieve, maintain, and seal if necessary. But what’s the difference between them?

The difference is that the satin polyurethane finish has a high level of flattening paste (or zinc oxide) which makes it has a low sheen. On the other hand, semi-gloss polyurethane has a low level of flattening paste (or zinc oxide), meaning it has more sheen. 

Satin finish due to its low sheen reflects less light, is dull, and is not shiny. Semi-gloss has a more lustrous appearance. Though not as shiny as high gloss, but shinier than satin.

Satin Polyurethane

Satin polyurethane has the third-highest sheen. Generally, polyurethane is a high-gloss finish but different requirements have made manufacturers produce it in sheens that are not too glossy. To reduce its sheen, manufacturers have included a flattening agent known as zinc oxide.

Satin polyurethane has a high level of this flattening agent in its formula, meaning it has a low sheen. Since it has a low sheen, the finish hides stains and imperfections on the surface. This makes it ideal for walkways and floors that frequently attract dirt. Its finish will last longer before you notice damages.

The finish is less lustrous, meaning it doesn’t reflect and has a dull appearance. The ability to hide stains and imperfections also means that it has relatively low maintenance.

Semi-Gloss Polyurethane

Semi-gloss polyurethane finish has the second-highest sheen. This is because the finish has a low level of flattening agent (zinc oxide) in its formula and more luster (or sheen). This makes it have a bright sheen that shows imperfections and damage.

However, semi-gloss polyurethane has more protection. The high sheen on the finish makes it less likely to develop scratch marks and dents. The high sheen also means that it takes longer to properly dry and set. But when it dries, it reflects light. This reflective feature of the finish allows it to reveal wood grain easily.

Semi-Gloss vs Satin Polyurethane

Here is a table that shows the main differences between these two finishes:

	Semi-gloss Polyurethane	Satin Polyurethane
Sheen	Moderate	Low
Dry-Time	Slow (takes about 48 hours to cure)	Good (cures in about 24 hours)
Scratch Resistance	Very good	Poor
Appearance	Shiny	Dull
Cleaning and Maintenance	Moderate	Low maintenance
Durability	Better	Good

Paint Formula

Both finishes have a very similar formula because they are both polyurethane. However, satin has a higher zinc oxide or flattening agent level in its formula. Semi-gloss has fewer flattening agents and more luster. This slight change in the formula of both sheens makes them different.

Most satin polyurethane finishes are water-based. However, semi-gloss polyurethane is usually oil-based.

Dry-Time

Satin polyurethane dries faster than semi-gloss polyurethane because it has fewer oils and less sheen which means the paint will evaporate and dry quickly.

Since semi-gloss has more sheen, it will take longer for the finish to cure and set because the sheen has to completely harden. On average, satin polyurethane will dry in 2 hours and cure in 24 hours. While semi-gloss polyurethane will take 4 hours to dry and 48 hours to fully cure.

The Sheen

Satin polyurethane has a low sheen when compared to semi-gloss polyurethane. The higher sheen of semi-gloss means it is more glossy or reflective. The lower sheen of satin makes the finish not as reflective or glossy.

The Appearance

The higher sheen of semi-gloss means that its finish is more reflective and glossy. Its finish looks like it was polished with oils. Satin polyurethane has a duller appearance due to its low sheen.

Cleaning and Maintenance

Satin polyurethane is easier to clean and maintain because it is not as glossy or reflective. Given its dull appearance, it will hide stains and debris perfectly. So you won’t need to clean it as much.

Since semi-gloss polyurethane is more reflective, stains will be more evident, so you’ll need more cleaning.

Durability

There isn’t much difference in terms of the durability of both sheens. However, semi-gloss polyurethane tends to be more durable. Its glossy finish makes it more water-resistant.

Also, its longer dry time means the particles have more time to harden and compact. This makes semi-gloss polyurethane more sturdy and likely to handle frequent use.

Scratch Resistance

Semi-gloss polyurethane is more scratch resistance than satin polyurethane. The glossy top coat of the finish is super flexible and resistant to scratch marks and dents.

Satin polyurethane reveals scratch marks and dents since it has no protective glass. As such, you shouldn’t use it on floors.

Paint Cost

There isn’t much difference in the cost of both polyurethane finishes but semi-gloss is often costlier than satin . One reason for this higher price tag is the extra protection you get with the semi-gloss finish.

Things To Know

Mixing Them

You can mix both types of polyurethane but the base must be the same. This means you can only mix water-based satin with water-based semi-gloss. The same thing applies to the oil-based types. 

If the sheens have different bases, you’ll ruin them if you mix them. 

Satin over Semi-Gloss Polyurethane

You can use satin over semi-gloss polyurethane. But, you must sand the semi-gloss finish first to remove its glossy layer. However, you can apply semi-gloss over satin polyurethane since it doesn’t have a glossy finish. 

Satin vs Water-based Polyurethane

Satin is not the same as water-based polyurethane. Water-based is a type of polyurethane dissolved in water, while satin is a type of finish.

Final Words

In summary, the different between satin and semi-gloss polyurethane is the level of sheen. Semi-gloss has a higher level of sheen so its finish is glossier, has better protection, shows imperfections, and takes longer to dry. While satin has a low level of sheen so its finish is textured, covers imperfections, and takes less time to dry.