Anatomy of a Sofa
It looks straightforward. An upholstered piece of furniture is little more than fabric stapled or tacked to a padded frame, right?
In fact, there's far more to achieving the crisp perfection and deep comfort of upholstery. That's why purchasing a new sofa (or chair) can be so expensive, and why even recovering a well worn heirloom is sometimes costly. That said, quality construction may be more economical than replacing a piece every 10 years or so.
Before you make the investment, it helps to understand what goes into making a well crafted sofa. After all, the bones of an item determine its value and longevity. With sturdy materials and hand-finished details, a custom piece can last 20 years or longer with new upholstery.
Once you understand the differences between feathers, down, and foam; jute and elastic webbing; and eight-way and zigzag springs, you can decide whether it's worth the effort to restore or update a beloved piece of furniture, or whether it's time to trade it in for a new one.
FRAME AND PADDING
These two components make up every upholstered piece, but their materials determine the overall quality. (1) A top-of-the-line frame, generally custom-made, uses 2-inch-thick kiln-dried wood, such as poplar, oak, maple, cherry or ash, and is secured with dowels and glue. Mass-produced pieces usually have thinner frames that are glued and stapled; lower-quality versions are often made of plywood or pressed board
Inside the frame, (2) jute webbing is woven along the seat and tacked to the frame with a pneumatic tack gun. The webbing is then threaded along the back and vertically along the arms of the sofa. (3) Eight-way springs, tied coil by coil to the webbing, offer the most support and flexibility. Other options are zigzag springs and elastic webbing.
Optional padding types (4) are horsehair (real, synthetic or a mix), foam and polyester batting. The casing is topped with (5) layers of glazed cotton (terylene), which helps grip the upholstery fabric and keep it from shifting. On a straight-backed sofa it also supplies the comfort in lieu of cushions.
CUSHIONS AND FABRIC
Structure aside, the cushions and (6) fabric on a sofa can also affect longevity. One way to prolong the life of upholstery is to opt for removable cushions so you can turn them over. The covers can be dry-cleaned easily, and if there is foam inside, you can see if it's crumbling and needs replacing.
For filling, down is the most luxurious — the super-soft feathers have no quills — but it's not ideal for everyday furniture. Other cushion options include down-filled casing, foam and cotton batting.