The Art and Science of Drywall
01/11/2022
Traditional construction methods often include the use of drywall for walls and ceilings. Installing and properly finishing drywall takes years of learning and honing particular skills, learning both the science and the art of the trade.
According to the Merriam-Webster Dictionary, drywall is:
A board made of several plies of fiberboard, paper, or felt bonded to a hardened gypsum plaster core and used especially as wallboard.
The History of Drywall
The most familiar brand of drywall, Sheetrock was created in 1916 by the U.S. Gypsum (USG) company. Originally the material was used in conjunction with plaster, but today, drywall technology has improved to the point where paint can be directly applied to the surface of it. Drywall is attached to wood or steel framing and can be finished with tape and joint compound to create a smooth wall surface.
Drywall replaced earlier wall finishes, primarily lath and plaster. The lath and plaster process was much more labor intensive than the methods we have today. Following WWII, a growth in suburban households and general home construction led to a significant increase in the use of drywall, with lath and plaster now nearly obsolete. However it can still be found in certain applications, particularly where durability and/or moisture control are important.
Drywall Sizes and Types
Drywall typically comes in 4’ x 8’ sheets, although it can be purchased in many sizes that are smaller, such as 2’ x 2’. It is often stocked in 10’ and 12’ lengths, as well. The material varies in thickness, most commonly 5/8”, 1/2”, 3/8” and 1/4″. There are a variety of board types that are utilized for different purposes:
Standard
This board is typical in wall and ceiling construction.
Mold Resistant
With a paperless backing and coatings that prevent the build-up of mold, this material is used in locations like bathrooms and kitchens.
Moisture Resistant
Used in bathrooms, basements, kitchens, laundry rooms and utility rooms where the drywall may be exposed to mold and moisture.
Fire Resistant
Made with glass fibers and an extra thick design, this drywall is typical for utility rooms, garages and locations near furnaces or wood stoves. It helps prevent the spread of fire by reducing the speed it can travel, generates less smoke, provides added sound control and is often required by building codes.
Soundproof
Thicker than standard drywall and with a noise-dampening core, this material helps reduce sound transmission through walls and ceilings.
Attaching drywall to walls and ceilings can be done with nails or screws, but we recommend screws for attaching the drywall to framing, as nails tend to ‘pop’ with wall movement, changes in moisture conditions and more.
The Installation of Drywall
Installing drywall requires some skill and is more of the “science” part of the work. It’s important that the boards are hung straight and plumb, which requires that the wall framing be straight and plumb as well. Ideally, each board is attached with screws and anchored into wall framing. The wall framing may be supplemented with wood or metal backing in locations where items such as shelving or furniture may be attached. The drywall boards are installed starting at the lowest elevation and stacked from there, with the seams on the vertical face staggered from each other. The staggered installation is critical to maintain the strength of the wall surface, as the joints are the weakest part of the wall.
Often, wall boards are installed with the length of the board placed horizontally, but some exceptions apply to this rule. If the top of the wall will be at the same dimension of the board length, the boards will be stacked side by side. This reduces the number of joints that need to be finished. Following wall installation, the seams of the drywall receive a layer of tape, followed by a joint compound, which is commonly referred to as ‘mud’. The mud is sanded and re-applied in multiple layers depending on the level of finish that is desired.
Finishing Drywall
The finishing of drywall is much more the “art” of the process. Training to be a competent finisher can take years to truly master. Architectural specifications dictate the level of finish, ranging from Level 0 to Level 5. These are described fully by the NW Wall and Ceiling Bureau in their Technical Resources page.
Level 0 is simply the installation of drywall with no joint compound or efforts to ‘flatten’ the wall finish. At the opposite end of the spectrum is Level 5, the highest quality level of finish, most often used in spaces with high quality finishes, such as high-end auto dealerships, office buildings, hotels and more. While the levels have descriptions, finishing drywall is not black and white. There is skill involved in completing the work and knowing how far to spread out the drywall mud with each progressive layer to make it truly smooth.
Joe York, current General Superintendent for Perlo remarks that, “The craft of drywall finishing is a true art. The best professionals have significant training and excellent craftsmanship. It takes time to master, and the people who are good at it are invaluable.”
Environmental Conditions for Drywall Installation and Finishing
The existing environmental conditions when drywall is installed and finished can make a big difference in the quality of the end product. Temperature and humidity effect the speed with which the joint compound material dries. This technical document for Gypsum Wallboard and Winter Weather provides a chart that outlines drying times for joint compounds.
Since drywall is often installed in buildings that are under construction and may not have complete heating systems, contractors must ensure that temporary heating and ventilation are running both during and after the work is completed. A failure to properly maintain the humidity and temperature can lead to excessive shrinkage, cracking, or simply delays in completing the work due to slow drying times.
A critical component of the heating and airflow is to ensure that the heat is not directed to only one location. Equally as important as having heat, the air must be evenly spread across the area. Typically this is accomplished using large fans to distribute the heat flow.
Careers in Framing and Drywall
Living wage jobs are available in the framing and drywall industry. Union apprenticeships range from $24/hr to $37/hour, with journeyman and foreman wages ranging into $40+/hour. When individuals are a part of the union, wages include benefits such as healthcare and retirement. The union offers trade training and classes, and connections with local companies for employment. Workers in these trades may work on both the exterior or interior of buildings, but are most often working in dry spaces.
Finding a Great Drywall Contractor
Many of the strategies to find a great drywall contractor follow the path we’ve previously discussed for finding great building contractors. If you’re looking for a great drywall contractor, here are some tips to remember:
- Verify licensing with the Construction Contractors Board.
- Verify that they have proper insurance.
- Ask to see examples of work through photos or, if possible, in-person tours.
- Ask for several references and call each to discuss their work.
If you have further questions about finding the right fit for your job, or need a consultant to review work in progress, the NW Wall and Ceiling Bureau may be available to help review your project.
Final Thoughts
In short, it’s important to note that the drywall trade is nuanced and requires training and skill to properly deliver. The quality of the drywall finish in a given space can make or break the ambiance of the room and can also affect the lifespan of the wall finish.
Lastly, we want to take a moment to thank our many drywall and framing partners for their work on Perlo’s projects. Thank you to Randy Clunas at The Harver Company for his contributions to this article.