Although a Level 5 finish generally produces better results than the more commonly specified Level 4 finish, it does not guarantee a flawless finish. Industry standards and MPI generally advocate specifying an ASTM Level 5 drywall finish (application of a skim-coat of drywall compound across the entire drywall surface) to help assure a satisfactory paint job for a ceiling or wall, especially in critical lighting conditions or when using non-flat finishes. With a flat finish, this can effectively prevent a noticeable difference between sections finished at different dates with material from different batches. Consequently, the spec should also require the painter to “blend back” the finish of each new section by shading the new topcoat back over the previous section with a spray gun. Very large ceilings are finished in phases, and it’s not reasonable to get all the paint from a single batch as is generally advocated for wall coating work.A ½ inch (15 mm) nap roller may offer the best and most efficient results. The stipple pattern of the roller can help to hide the underlying texture variations in the drywall. Even if the initial finish was sprayed, the spec should require backrolling the ceiling finish.Optimal results are more likely to be achieved if the specification requires an ASTM Level 5 drywall finish.The following list of best practices outlines a few tips for optimizing ceiling painting projects. If inspection work occurs with when lighting is brighter than the permanent conditions of the space, time and money could be wasted repairing defects that will be invisible upon completion of the project. If inspection occurs when lighting is lower than the permanent conditions of the space, “new” surface defects will become visible once brighter lighting is installed. It is important to perform the final inspection after setting up the permanent lighting conditions for the space to determine which defects will be visible once the project is completed. Lower ceilings tend to make ceiling defects more visible as the viewing angle becomes more acute.Ĭritical lighting conditions caused by either natural light from windows or from ceiling-mounted fixtures can exacerbate the problem. Generally, defects in a ceiling’s finish are only visible when viewed at an angle. These defects are caused by a variation in texture and porosity between the paper coating and the drywall filling compound (paper absorbs the applied coating at different rate than the filling compound, creating an uneven surface). We’ve discussed the challenges of obtaining a satisfactory finish with new drywall on a few occasions, so it is probably no surprise that achieving a smooth, defect-free finish on a ceiling can be even more difficult. But nowadays, especially in medium to high-end construction, many owners and architects prefer a flat, smooth drywall ceiling surface. This helps hide flaws in the finish that otherwise might be quite visible. Based on the experience of PQA Inspector Dave Lick and MPI’s Level 2 Architectural Coatings Specialist courseīack in the day, ceilings were often finished with spray textured surfaces consisting of polymeric binders or modified plaster and aggregate to create a “spatter” effect.
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