Skim Coat vs Putty – Comparison and Some Key Facts

Some people mistakenly believe that skim coat and putty are interchangeable. If you are trying to decide which of these two is best for your project, you have come to the right place. We will discuss everything you need to know about these two products and help you figure out which one is best for what.

Read on to learn more about

  • The general uses of skim coat and putty
  • Similarities between skim coat and putty
  • Differences between skim coat and putty

General Uses of Skim Coat and Puttty

Skim coat is a thin plaster or joint compound used in the construction and finishing for a wide range of purposes. Professionals like skim coat because it can be applied to different surfaces, including masonry, plaster, drywall, or concrete. In prep work, a skim coat is used before applying paint or wallpaper to create a smooth, even surface that increases the visual appeal and durability of the finish.

The construction industry uses skim coats for texture removal, wall repair, ceiling repair, decorative finishes, and resurfacing. The product can also be used to repair damage like small cracks, uneven texture, or dents. Skim coat can be used to achieve a smooth or textured finish depending on the application techniques used. This versatile material is often used by professionals to efficiently achieve flawless results on a wide range of projects.

Putty is multipurpose filler material that is used in several industries, e.g., automotive, woodworking, and construction, to repair damage on metallic, wooden, or plastic surfaces. This pliable material’s not-so-secret superpower is the ease with which it can be molded into cracks, holes, or gaps in between surfaces. It can also be used to prepare surfaces for finishing by creating a smooth, even surface.

Putty is usually made of polymers, gypsum, calcium carbonate, and several additives that improve the product’s adhesion, durability, and versatility. It is available in different forms, including water bases, oil-based, and epoxy based. Each form of putty has distinct properties and uses.

Differences Between Skim Coat and Putty

As we mentioned above, though the uses of skim coat and putty often intertwine, the two products are quite different. Here are the key differences between skim coat and putty:

1. Level of Expertise

Skim coat requires refined techniques that only professionals or advanced DIYers can achieve with ease. If you aren’t sure that you can apply multiple thin layers of skim coat perfectly, you may be better off with putty. Putty is easy to apply, mold, and sand. It also takes much less of your time than a skim coat.

2. Surfaces

Putty can be used to fix almost anything. Don’t try on your tooth cavity, though! You can use putty on many surfaces, including concrete, brickwork, plastered walls, plastics, metal, wood, you name it! Skim coat is mainly used on walls and ceilings. No one uses skim coat on anything but masonry, plaster, drywall, or concrete.

3. Purpose

Putty is much more multipurpose than skim coat. While skim coat is predominantly used in construction and finishing, putty is used beyond these industries. It is also used to repair in the automotive and woodworking industry.

Skim coat is also much more durable and suitable for construction than putty. Remember that putty is primarily a filler material for covering imperfections, whereas skim coat is a heavy-duty, versatile finish. If you are looking to fix a small crack, a skim coat is likely overkill. On the hand, when performing large-scale preparation for finishing, e.g., on walls and ceilings, it would be best to use skim coat.

4. Application

Putty is much easier to apply than a skim coat. Its soft, pliable consistency is easy to shape and mold using a putty knife. Skim coat, on the other, needs to be meticulously applied in multiple thin layers using a trowel. When applying the skim coat, you need to work quickly and apply a thin, even layer without any streaks or bumps. Enough time must be allowed for one layer of skim coat to dry before the next one is applied.

Skim coat is rarely used by beginners because putty allows them to do the same with much less hassle. All you need to do is slap the putty to the surface and shape it to blend seamlessly with the surrounding.

5. Variety of Products

Puty is available in epoxy-based, oil-based, and water-based formulations. These products allow consumers to select the product that best fits their project and budget. Skim coat is usually made of joint compound or plaster and relies on this simple formula to suit diverse projects.

6. Affordability

Putty is much more affordable than skim coat. Not only does it usually have a lower price tag, but you are also likely to use it much less. While putty is applied in a single layer over the damaged section or the entire surface, skim coat is applied in multiple layers. Most DIYers prefer putty to skim coat because you are likely to use less and less likely to mess up.

7. Drying Time

Although both skim coat and putty need time to dry, skim coat takes significantly longer. When using skim coat, you will need to allow enough time for each of the multiple thin layers to dry off. With putty, you only need to allow one cut to dry off.

The exact amount of time needed for drying and curing will differ depending on the type of product used, weather conditions, and the number of layers applied. Generally, putty dries after about four hours but should be left overnight for the best results. Skim coat takes between twelve and twenty-four hours to dry. If you decide to use three layers, it could take about three days to complete the process.

8. Sanding and Finishing

While both putty and skim coat can be further prepped after their application, e.g., sanding, painting, or staining, putty often calls for more work than skim coat. Skim coat is applied in multiple layers that guarantee a smooth, even finish. When applied perfectly, the skim coat does not need to be sanded.

Putty is applied in a single coat and often needs a fair amount of sanding and finishing to ensure it seamlessly blends. Ensure you never use more putty than necessary because you are likely to spend a lot of time sanding it off to achieve an even finish.

Similarities Between Skim Coat and Putty

People do not mix up putty and skim coats without good reason. There are various similarities between the two products that lead people to mistakenly believe they are interchangeable.

1. Surface Preparation

Skim coat and putty are both used to prep surfaces for finishing. They are efficient at concealing damage like dents, cracks, and uneven textures for the perfect application of paint, wallpaper, or other finishes. Skim coat just happens to be good for much more, while putty generally isn’t unless you are a beginner or on a low budget.

2. Application Tools

Skim coat and putty are both applied using tools like trowels and putty knives. Any tool that can efficiently spread and even out the products onto the surface can apply both products.

3. Versatility

Both putty and skim coat are good for more than one thing. They can be used in construction, finishing, and repair work. Both products can also be applied on multiple surfaces, including drywall, concrete, plaster, and masonry. Putty is more versatile because its uses extend to plastic, metal, and wood.

4. Finishing

Once you have achieved a smooth finish, it will be impossible to tell whether you used putty or skim coat. Both products provide an excellent adhesive surface for painting, staining, or wallpapering.

Factors to Consider When Selecting Between Skim Coat and Putty

After taking all this information in, you should be ready to decide which works best for you, between skim coat and putty. In case you need a little extra help, here are some factors to consider.

  • Skill level – if you are not great at DIY projects, stick with putty.
  • Budget – if you are on a low budget and want a little product to go a long way, putty is the best choice for you.
  • Time and energy – if you are unwilling to spend a lot of time and energy on the project, go for putty.
  • Repair work – putty is perfect for repairing minor imperfections. There is no need for a skim coat when doing minor renovations.
  • Construction work – skim coat is better suited for work that is expected to be placed under a lot of stress for long periods.
  • Surface preparation – if prepping a large surface without a lot of experience, use putty. Otherwise, skim coat is a superior choice for long-lasting surface preparation that protects your finish from peeling or chipping off.

Conclusion

Two different products have never been more alike, but we trust you now feel confident to make an informed choice. Whichever product you settle on, be sure to read the labels carefully before picking one off the shelves. You can also ask a staff member at your local home improvement store for the best choice for your particular project.