Plaster vs Drywall: What's the Difference?
Choosing your wall finishing is a decision that needs to be carefully considered during construction. Fortunately, you're most likely only deciding between drywall or plaster. Plaster and drywall each have their pros and cons which you should be aware of before making your selection. In this blog, we will help you determine the pros and cons of each, how to tell the differences, and more.
Pros and Cons of Plaster and Drywall
To understand the differences between plaster and drywall, we've created an in-depth pros and cons list of both in their practical settings.
Understanding Plaster
Plaster is created by nailing laths (strips of wood) together over wall studs, then covered with layers of plaster, leaving a smooth surface behind. The plaster used by builders for plaster walls is typically made of lime from limestone or gypsum plaster, water, and sand. While it's denser and stiffer than drywall, it doesn't have a uniform thickness. Plaster walls are commonly found in buildings that date back before World War II, and are often used on partition walls and ceilings.
The installation process for plaster is notably more expensive because it requires more specialized skill and more time than drywall installation. However, when completing a materials comparison they are similarly priced. Before you set your heart on a plaster wall, ensure that there are adequately skilled laborers available in your area.
The most common installation method of plaster begins with covering the framing studs with wood laths or metal meshing. From there, a base coat of plaster to cover the gaps between the wooden planks is laid, and once that has been set, two to three topcoats are layered on to create a smooth finish. This process is comparable to applying stucco to the exterior walls of a home.
Here are some of the quick pros and cons of plaster compared to drywall:
Pros
- Plaster is more sound-proof because of the wood lath and layers of plaster.
- Plaster has a higher-end look and feel.
- Plaster is more fire-resistant than drywall.
- Plaster has easier installation on contoured walls, compared to drywall.
Cons
- Plaster is known to be more expensive, not due to the materials used, but the specialized labor it requires to install.
- Plaster is more fragile than drywall and once the home is settled there is a higher chance of cracks.
- Plaster makes future upgrades and repairs more challenging because it is harder to cut into.
- Due to the density of plaster, it can sometimes block WiFi signals. This can be resolved using a WiFi extender or a powerline adapter.
Understanding Drywall
Manufacturers compress gypsum to create drywall sheets, which typically have fixed widths and lengths, often measuring 4' by 8'. These planks of wood must be either nailed or screwed into the studs in the wall. Then builders use a plaster-like compound called Joint Compound will be used to bond and smooth the surface.
Joint compound mixtures are made up mostly of gypsum dust and water, which helps to fill in the joints of drywall, patch holes, or other minor damage. This process helps put up walls with less training and time, making it more affordable than plaster walls.
Drywall grew notably more popular after and during World War II because of the cost. While these construction materials are priced similarly, it is the simple installation and less labor that makes drywall so economically friendly.
Here are some of the quick pros and cons of plaster compared to drywall:
Pros
- Incredibly smooth when put up correctly.
- Notably better thermal insulation when compared to plaster.
- Manipulatable when dealing with in-wall repairs and upgrades due to the ability to create and repair holes.
- Drywall is more price friendly than plaster, due to it being less labor-intensive.
Cons
- Notably more challenging to move materials and may need additional machinery to do so. This type of machinery includes aerial lifts to help lift and position the sheets before setting them in place.
- Drywall isn't as dense as plaster walls and is less soundproof as well.
Is it Better to Plaster or Drywall?
While one is not better than the other, one might be better for your project than the other. Some of the key factors to consider are cost, installation process, durability, soundproofing, and aesthetic appeal. While plaster is notably more expensive with a longer installation process, it continually proves to be more durable.
In contrast, drywall is less expensive due to the less expensive labor cost and has a shorter installation time period. While drywall is known for less durability, future repairs, and modifications are much easier to fix. Both materials provide different aesthetics, and it is up to you which matches your project best.
It makes the most sense to choose plaster over drywall when design and architectural details are important to the structure. This includes restoration projects where historical accuracy matters. And where the appeal and aesthetic matter to the finished product. Plaster is also more resistant to damage compared to drywall.
One scenario where you might choose drywall over plaster walls is when working on a modern commercial office building. It makes more sense to choose drywall because of the clean lines and more cost-effective approach. Faster installation is helpful to remain on schedule, the low-cost help to stay on budget, and the ease of modification allows for flexibility in layout.
How Can You Tell The Difference Between Drywall and Plaster?
Plaster is typically denser and comparably more fragile than drywall and drywall has different levels of thickness but is not as dense or as soundproof. Drywall also has notably better insulation and simpler installation which can make up for the lack of density. However, from the untrained eye, they may not look that different. Here are 5 simple ways to tell if you have a drywall or a plaster wall.
The most common way to test the wall is to perform the pushpin test. You can simply take a pushpin and press it into the wall using your thumb. If the pin is able to easily penetrate the wall, it's drywall. If it doesn't, then it's plaster (or you may have just found the stud).
One of the least physical ways to find out if your home has drywall or plaster is to find out when your home was built. If your house was built before the 1940s then it is most likely plaster. Plaster was the more popular material used during that time period.
If your house was built between the 1950s-1960s then it's possible that your walls are either plaster or drywall. If your house was built after the 1960s then you know that you most likely have drywall up.
Another test that is simple and effective to perform in your home is the tapping test. Simply gently tap on the wall's surface with your knuckles and listen to the sound. If you hear a solid, dull thud sound then you have a plaster wall. But if you hear a hollow or resonating noise, then you're most likely dealing with drywall.
Another test you can perform is to inspect your walls for cracks and flaking paint. While drywalls aren't likely to develop cracks, if you do see them they'll be in smaller areas. These areas most often are where a joint compound is used to seal seams or patch holes.
However, plaster walls typically have spider web-like cracks all over and not in a localized spot. Plaster walls are also prone to flaking paint.
Lastly, feel free to check out the attic, basement, or behind the walls to help you determine what wall you have. When assessing the wall studs, if they are standing vertically and spaced further from each other, then that's drywall. The spacing of these wooden studs is the reason that drywall sounds switch between hollow and dense when knocking around. If you see plaster seeped out between the laths, loose wiring, and evenly sized wood strips then you know it's plaster.
Can You Plaster Over Drywall?
While it is possible to use plaster over drywall there are multiple factors to consider when using plaster over drywall. Firstly, ensure that the existing drywall is in good condition and that any structural issues with the drywall have been addressed before applying plaster.
Another factor to consider is if the plaster being used is compatible with drywall. As some plasters have specific limitations regarding their application to drywall, so ensure that you've consulted the manufacturer or a professional.
Some of the drawbacks of using plaster on drywall are the limited bonding which might not adhere properly to the drywall. One of the ways to limit this is through proper preparation and priming. One of the most common issues with applying plaster to drywall is cracking and shrinking. These cracks can appear on the surface of the plaster layer, especially if it is applied too thick or improperly.
Making the Right Choice: Plaster or Drywall
Choosing between plaster and drywall should be based on the specific needs of your project. If budget is more important than soundproofing, drywall will be better for your project. If there will be lots of traffic in this area once the project is done and design is a major factor then plaster will be better suited for the job.
The key differences between the two are the hardness and density of each, the cost, and the aesthetics you are hoping to achieve. No matter which you believe is best, consulting a professional when deciding between both is the best way to decide which is optimal for your project.
