When the frame is beautifully built and the design carefully considered and constructed, we move onto cushion fillings and springs. The cushion density has to suit the character of that particular chair. We use a combination of foam, fibre, duck feathers and down (for extra loftiness), because none of them are quite sufficient on their own. You want to sink-into your sofa, but you don’t want to feel like you need to be constantly plumping. Sofa cushions need to bring together comfort, shape and rebound. Each chair is designed with a different filling ratio. Consider George, a sleek, architectural sofa whose cushions need to be less-domed, unlike Olivia whose classic shape very much requires a pillowy silhouette. As for the springs, we favour the more modern alternative to the coil spring: serpentine springs and elastic webbing.