This felt weight is a good budget option if you have a standard roof. For roofs with a steeper slope, you should always opt for 30-pound felt instead of 15-pound. This is essential because of its increased anti-slip protection and tear resistance. If you opt for a thinner felt on a steep roof, it's more likely to break.
Some customers prefer 30 lb felt paper because it's a thicker product, less prone to breakage, and should wear out better over time. In addition, on steeper roof slopes, 30-pound felt paper is needed for the installer's anti-slip protection, and is also less likely to break during shingle installation.