Flannel fabric is known for its softness and warmth, making it comfortable for use in various temperatures. However, whether a sofa flannel fabric is considered breathable depends on its specific composition, weight, and weave. Here are some considerations 

regarding the breathability of sofa flannel fabric:

Natural Fibers vs. Synthetic Fibers:

Flannel can be made from various fibers, including natural fibers like cotton or wool, as well as synthetic fibers like polyester. Natural fibers tend to be more breathable than some synthetics.

Cotton Flannel:

Cotton flannel is often praised for its breathability. Cotton is a natural fiber that allows air to circulate, making it suitable for comfortable seating in different temperatures. Cotton flannel can provide warmth in cooler temperatures without feeling overly stifling.

Weave Construction:

The weave construction of the flannel fabric can impact its breathability. A looser weave allows for more airflow, enhancing breathability. However, a very loose weave may compromise the fabric's overall durability.

Weight of the Fabric:

The weight of the flannel fabric also plays a role. Heavier weight flannel fabrics may provide more insulation and warmth but might be less breathable. Lighter weight flannels may be more breathable but may not offer the same level of warmth.

Wool Flannel:

Flannel made from wool fibers is known for its warmth, but wool can be breathable as well. 

Wool has natural moisture-wicking properties, helping regulate body temperature and providing comfort in various climates.

Blend Fabrics:

Some flannel fabrics are made from blends of different fibers. For example, a cotton and polyester blend might offer a balance between breathability and durability.

Seasonal Use:

Consider the intended use of the sofa in different seasons. Flannel can provide a cozy feel in cooler months, but it may feel warmer in hot weather. If you live in a climate with extreme temperatures, you might choose a flannel fabric that suits the predominant weather conditions.

Personal Comfort Preferences:

Personal preferences for comfort can vary. Some individuals may find flannel to be comfortable and breathable in a wide range of temperatures, while others may prefer different upholstery materials for warmer climates.

It's advisable to test samples of the flannel fabric if possible and consider factors such as the room's temperature, your personal comfort preferences, and the climate of your location. Additionally, inquire about the specific composition and characteristics of the 

flannel fabric when purchasing to ensure it aligns with your expectations for breathability and comfort.