Upon close examination you will usually find some type of upholstery spring used in the base construction of chair and sofa seats. Since each type has its own particular features, they each will produce different seating comfort.
We are going to acquaint you with the most common springs that have been and are used in furniture construction. You will then be able to identify them when you encounter them in your various reupholstery projects.
Coil Springs for Upholstery
The “double coil” spring has a larger open coil at each end. They are sold by the pound, but you buy the number of springs you require. They are available in different heights and firmness.
They must be fastened to a webbed, wood or metal strap seat foundation. Next, they are anchored to the frame.
This is done by tying them to the desired height and firmness using spring twine. Sometimes this is referred to as “8-way hand tied”. This is the best way, but not all tying follows this method.
Springs are equally spaced and attached from the back to the front of the seat frame. A clip is attached to each end of a spring, then the clip is nailed, screwed or stapled into the seat frame.
After determining the length required and the number of pieces, the lengths of spring are cut from the roll with a wire cutter. There is a lot of pressure involved with this spring, whether in the original roll or in a cut length.
Sometimes this pressure can cause a frame to bend or warp. Because of this pressure, sometimes the frame has to be re-enforced to prevent the bending or warping.
This spring is referred to by many names. Here are a few of the names: zig-zag, no sag, sinuous, serpentine, s-curved. A roll really resembles a continuous “s” curve which is somewhat heavy and difficult to unwind.
These are pre-assembled single coil springs on a metal bar that is attached to the chair frame with nails or screws. The coils are larger at the top and smaller at the bottom where it is fastened to the bar.
Normally, there are 3 or 4 coils on a bar. Bars may be available in 21 to 24” lengths to fit the opening of the chair seat frame.
Older textbooks sometimes referred to them as a “spring metal bar”. They are not very common any more. And they are difficult to locate if you need to replace any in a reupholstery project.
Upholstery springs Overview
Springs can give more comfort to your upholstered seating projects. A furniture frame may well dictate the type of spring that will work best. Other factors can also come into play as well.