Choosing the best weaving wool depends both on the project and the role played by the wool in the project. One important thing to consider is how strong the wool must be in order to be effective in the project. Warp wool must be very strong and consistent in most cases, but wool used as a weft yarn can be more delicate because it does not need to stand up to as much tension. Other things to consider when choosing weaving wool include the weight of the wool, colors, and the type of wool chosen. Differences among wools can drastically change the look of a finished project even when the technique or pattern used does not change.
Weaving with wool can create textiles of incredible durability and warmth. Some types of wool are very soft, such as merino, but others are somewhat coarser. Wool blends are often able to match the warmth of wool with the softness needed in garments. For utility projects like woven rugs, coarse yarn may actually be a better choice. The best weaving wool for any given project depends on the use of the project.
Wool is often dyed beautiful colors, but wool in natural colors can also yield interesting effects. The weight of the wool yarn will affect not only the thickness of the finished piece, but also the way the yarn creates patterns. For example, a light warp with a thick weft yarn will create a very different piece than two evenly matched yarns, even if the weaving pattern is the same. Experience is often the best teacher when planning weaving projects, but simply thinking about how yarn will look when woven is often enough to provide a general idea of the finished textile.
As far as the actual quality of the weaving wool, it is often necessary to feel the wool in person in order to determine if it is appropriate. Some brands have a reputation for strength and durability, and sticking with these brands of yarn is a good way to ensure a consistent weaving experience. Handmade wool yarns can be very beautiful and may be appropriate for many weaving projects, but it is important to make sure you have all the yarn you will need because dye lots can be relatively small with handmade yarns.
Weaving wool can be expensive, but inexpensive yarn can also be used for many projects. This type of simple yarn is often ideal because weaving uses a lot of yarn. Elaborate yarns used for knitting and crochet can be used for weaving, but it is often better to use simple and inexpensive yarns and allow the weaving patterns to provide visual interest to the finished wool piece.