Many stucco tapes are constructed to with a UV-resistant backing because they are for use on exterior surfaces, often in hot, sunny climates. Sunlight contains harsh UV rays which can cause negative changes to the physical properties of many tapes. Certain components of tapes, such as rubber adhesives and polyethylene (PE) backing can become hard and brittle as a result of prolonged exposure to UV rays. If the tape is unable to retain the physical properties that allow it to bond to stucco windows, door frames, and other surfaces involved in stucco work, it is at a high risk of failure.
UV-resistant tapes are ideal for stucco applications because in most projects, the tape will be used on exterior surfaces and exposed to the elements for a prolonged period of time, sometimes as long as several weeks. The value of using a UV-resistant tape is that it gives the tape more durability against sunlight exposure so that it can retain its adhesion and stand up to the job.