Using regular indoor cushions on urban outdoor furniture like balcony sofas or patio chairs is not recommended. While convenient, indoor cushions lack essential protective features. They are typically made from fabrics like cotton, linen, or velvet, which absorb moisture quickly. This leads to mildew, mold, and unpleasant odors after rain or humidity. The filling, often polyester fiber or down, clumps and loses shape when wet and dries slowly.
Outdoor cushions are specifically engineered for exterior conditions. Their fabrics are solution-dyed acrylic, polyester, or vinyl with UV inhibitors to resist fading from sun exposure. They are tightly woven and treated for water resistance, causing moisture to bead up and roll off. The fill is quick-drying foam or recycled plastic fibers, and construction includes drainage grommets. For urban settings with limited storage, all-weather cushions provide durability against sun, rain, and pollution without needing constant cover.
In short, for longevity and hygiene, invest in purpose-made outdoor cushions. For temporary use, always bring indoor cushions inside immediately after use, but expect reduced lifespan and potential damage to both the cushion and your furniture.