Drywall is a common gypsum-based construction material employed to create the level surfaces of ceilings and walls in most contemporary residences. Drywall is a handy alternative to plaster. It is also commonly known as wallboard, gypsum board, plasterboard and Sheetrock (a popular trademark name owned by U.S. Gypsum Corporation).
Drywall is available in various sizes and thicknesses, ideal for various applications. Fortunately, most manufacturers offer standard measurements to facilitate the selection of the proper drywall. However, it is crucial to understand the differences in drywall dimension and thickness to achieve optimal results in different uses.
What is ½” Drywall
The 1/2 inch is the most common drywall on the market today. It’s ideal for most applications and common in most local hardware stores. It can be used for ceilings; interior walls, and most DIY enthusiasts can independently lift and install panels of this size. Additionally, the ½ “is sold in different sizes, with the smallest being 4×8 foot panels. Hobbyists often use 4×8 boards, while professionals use a mix of sizes.
What is 5/8 Drywall
5/8-inch-thick wallboard is also known as firewall drywall. Due to its thickness, it is the best drywall for soundproofing projects in noisy buildings. 5/8-inch drywall is also ideal for installation on walls and ceilings with no sagging. This drywall rarely finds a place in homes because it is heavy and costlier than other options.
1. Thickness
There are four distinct drywall thickness standardized by all manufacturers. They include:
- 5/8-inch (15.9mm)
- 1/2-inch (12.7mm)
- 3/8-inch (9.52mm)
- 1/4-inch (6.35mm)
5/8 Inch (15.9mm) Drywall
This is the thickest option you can get. It’s ideal for commercial purposes, and it’s commonly known as firewall drywall, and its thickness makes it perfect for soundproofing. It can be used on walls and ceilings but is not widely used in residential settings as it’s more expensive and heavier than all other drywall sizes.
½ inch (12.7mm) Gypsum Panels
It’s also known as the standard Drywall, often used for ceilings and walls and common in most residential homes. It can be used with both wooden and steel frames.
The other two options are considered economical, with the 3/8 inch-perfect for remodeling projects. Since they are so thin, these panels have to be handled with great care to prevent them from breaking.
Verdict: Thickness and mass are integral in both durability and soundproofing effectiveness. Since 5/8 is much thicker than ½ inch drywall, you get much more durability and noise reduction effectiveness with the former than the latter.
2. Soundproofing Effectiveness
To dampen the “noise” by 75%, a reduction of 10 decibels is required. An increment of the STC from 34 to STC 64 results in sound dampening by around 30 decibels. To improve the soundproofing effectiveness of a wall, drywall sheets must be installed on either side of the wall.
The 5/8″ is thicker and doesn’t bow down when installed on the ceiling, even when the studs are spaced more than recommended. This way, you get a much flatter ceiling regardless of the room size, something that you won’t get when you use thin gypsum boards that tend to bend.
The 5/8 also does a fantastic job when it comes to soundproofing. The more the mass, the more effective a material is in blocking noise transmission.
Verdict: The 5/8 is more durable and offers the best soundproofing result than the ½” inch wall panels.
3. Weight
The standard 5/8″ gypsum is heavier compared to the ½ inch drywall. That’s why you will need more people’s assistance when installing these panels in your home. However, with the advancement in technology, manufacturers have designed a 5/8″ drywall panel dubbed as USG UltraLight Firecode Tapered Edge Gypsum Board that’s lightweight compared to traditional 5/8″ thick drywall.
These state-of-the-art panels are 30% lighter, approximately 27 pounds lighter than their standard counterparts.
Weight reduction, however, doesn’t affect performance, durability, effectiveness, or even appearance.
The only downside with the USG Gypsum boards is that they’re not highly effective in noise reduction, fireproofing compared to the standard 5/8 boards.
If you’re not looking to soundproof or probably get the best material with good fireproofing ratings, then USG gypsum boards are the perfect choice for you.
They are perfect for anyone looking for improved strength and impact resistance, especially in commercial and high-end homes.
A standard 5/8″ sheet of gypsum board measuring 4×8 feet weighs 74 pounds.
4. Cost
I’m sure you probably think there’s a considerable price difference between the two types of drywall sheets. Well, the price difference per panel is quite negligible, and you’re better of with the 5/8″, taking durability and soundproofing capabilities into consideration.
Below is a table showing the price difference between the available drywall sheet sizes for both 1/2″ and 5/8-inch gypsum panels.
| Type | 4′ x 8′ | 4′ x 12′ |
| 1/2″ | $12 – $18 | $15 – $24 |
| 5/8″ | $14 – $20 | $18 – $27 |
If you intend on doing a significant remodeling or soundproofing project, I would highly recommend you purchase in bulk, and you are most likely to get at wholesale prices or at a discounted price.
5. Insulation
The R-value measures the resistance of an insulating material to heat transfer. This term is typically used for identification when purchasing insulation materials. R-values can vary based on the direction of thermal movement within a product. Insulation with a greater R-value improves thermal efficacy.
R-values are additive. For example, if an insulating material with an R-value of 12 is affixed onto another with an R-value of 5, the combined R-value of the two materials is 17.
Typically, the R-value of drywall is reported as 0.5. However, depending on the product’s thickness, it ranges from 0 to 1. Therefore, it is not a suitable alternative to other insulation techniques.
- ½ inch drywall R- Value 0.45
- 5/8-inch drywall R- Value 0.5625
6. Application
The 1/2 inch is the most common drywall on the market today. It’s ideal for most applications and common in most local hardware stores. It can be used for ceilings; interior walls, and most DIY enthusiasts can lift and install the panels of this size on their own. Additionally, the ½ “is sold in different sizes, with the smallest being 4×8 foot panels. Hobbyists often use 4×8 boards, while professionals use a mix of sizes.
5/8” drywall can be utilized as a fireproof buffer and can also be used to soundproof the basement ceiling in two-story residences. It is also suitable for use in commercial building projects.
7. Fire Resistance Rating
Due to the extra-thick construction, 5/8-inch drywall has proven more fire-resistant than its thinner counterparts. To comply with building regulations for fire rating, however, manufacturers make this thickness even more fire-resistant, and 5/8-inch drywalls are either Type X or Type C for fire-rated assemblies.
These unique varieties of drywall contain additives that enhance their fire resistance. Type X is reinforced with fiberglass, which prevents the formation of fractures as the board flames, allowing it to last longer without failing.
Type C boards contain even more fiberglass reinforcement and material that expands in a fire at the same rate as the drywall board contracts, further reducing fractures while improving stability and time to failure.
In addition to their fire resistance, 5/8-inch boards are stiffer, making them a good choice for ceilings, where they are less likely to sag – particularly if you plan to add a heavier texture.
Similar to 12-inch drywall, 5/8-inch drywall comes in an array of sizes, beginning with 48 and increasing in size. The width also makes it more suitable for commercial applications or noise-isolating situations, such as the shared walls of duplexes.
Pros And Cons Of 5/8″/15.9mm Drywall Panels
- Good Sound Dampening– thicker Drywall gives the best performance restricting noise transmission.
- Fire And Mold Resistance– they’re are thicker and more resistant to moisture than their counterparts.
- No Sagging– because the 5/8″ is thick, you won’t experience sagging, unlike when using thin wall panels which bend easily.
- Top-Notch Insulation– you get better insulation when using a thicker sheetrock panel than thin ones.
Cons:
The 5/8 sheetrock panels are much heavier than all other panels making them more challenging to install.
Additionally, they’re more expensive and less flexible and hence not ideal for curved surfaces where flexibility is much needed.
Pros And Cons Of 1/2 Inch Drywall Panels
You’d be surprised to learn that using thin drywall panels has advantages. The pros for the ½ drywall panels include:
- Lighter- and hence easier to install them on your walls and ceiling
- Affordable- making them perfect for anyone who’s on a budget.
- More flexible- hence fantastic for curved surfaces
Unfortunately, they are bad for the ceiling as they tend to sag and droop with time. Additionally, they are less effective when it comes to soundproofing.
References:
- https://wallboardtrim.com/drywall-thickness/
- https://medium.com/@wbcaoutreach/the-go-to-guide-for-drywall-size-and-thickness-a901081b9fc5
- https://www.thespruce.com/types-of-drywall-845079
- https://www.archtoolbox.com/r-values/
- https://www.e-education.psu.edu/egee102/node/2064
Meet Mike O’Connor, (a DIY enthusiast), living in Cincinnati, a city ranked as the noisiest in the USA.
As a work from home dad, I have a first hand experience of how noise can truly affect your well being.
Soundproofing isn’t something that should be taken as a hobby, it should be a skill that every homeowner should be equipped with.
Most of the work documented on this blog comes from purely first hand experience, and the products recommended work as indicated.