Donald E. Smith, CCS
September 2007It’s been a while since questions about finishing gypsum wallboard came across my desk, but I recently received two questions that sounded interesting.
The first concerned the application of a textured finish on an existing plaster ceiling in a shopping mall. While the caller was not specific about the exact texture applied, it consisted of drywall joint compound sprayed using a hopper gun. Three months after completion of the work, the owner and architect decided they did not like the appearance of the texture.
The contractor was looking for an industry standard to use in justifying the quality of the installation to the owner and architect. Sadly, there is no standard available. So just how do you prevent this from happening to you? How do you satisfy the expectations of the owner and architect when there are no standards available? The simple answer is to establish a level of quality prior to beginning the work. In some instances the architect will specify a sample or delineate an area of the project to be used as a sample to establish the level of quality of the work. As I said, this happens sometimes, but more often than not it does not happen. Of course when you bid a job, if there is a sample or mock-up specified, you will include that cost in your estimate—after all, it does cost you time and material.
A sample mock-up is especially critical when dealing with a Level 5 Finish. There are misconceptions of just what a Level 5 Finish is and how it should look. I receive more calls on perceived problems with a Level 5 finish than any other level of finish. Some people have the misconception that a Level 5 Finish is a substitute for a veneer plaster finish. In fact GA-214-07, Recommended Levels of Gypsum Board Finish, specifically states: "A skim coat will not approximate a plastered surface.” ASTM C804, Standard Specification for Application and Finishing of Gypsum Board, contains the same statement.
When designating a sample area of a project, make sure you work with the painting contractor since he will be following after you to complete the final decorating of the drywall. The sample should have the specified painting system applied prior to requesting acceptance from the owner and architect. Another consideration is the location of the sample area. If there is a critical lighting situation, make sure the area you have selected reflects this condition. The other critical factor in the inspection process is that the surface in question should be viewed at a normal angle, without magnification, from a distance no closer than 5 feet.
While using this process will cost money in the long run, you will save time and frustration at the end of the project.
The second drywall question came from a manufacturer and involved a Level 5 finish. Their marketing department was interested in the percentage of premium that is added to a Level 4 finish when a Level 5 finish is specified.
I consulted a couple of AWCI members as well as looking at some historical cost data to determine the difference. Both of the members are directly involved in preparing estimates and work for large drywall contractors in two different markets. We only addressed walls and not ceilings, but both indicated that ceiling work would be more costly than walls due to the working conditions.
The premium added is in the range of 25 to 35 percent. Needless to say the bulk of the additional percentage is the labor required to apply the skim coat of joint compound over the entire wall surface. One of the estimators added that in some cases they increase the percentage to cover the owners’ expectation factor. Here again the owners’ expectation enters into the picture as does another case for insisting on acceptance of a sample area to ensure success of the project.
Interestingly enough, the Level 5 finish was developed to eliminate some of the shortcomings of a Level 4 finish. The intent was to produce a uniform finish and a consistent surface to receive the application of the final painting system. The directions for achieving a Level 5 finish in GA-214 also include methods for eliminating tool marks and ridges. Of course it goes without saying that a highly skilled mechanic is required to produce a Level 5 finish, and the owner and architect need to be aware that it is the work of an artisan and not the produce of a machine.
About the Author
Donald E. Smith, CCS, is AWCI’s director of technical services. Contact him at email@example.com or call (703) 538.1611.