Upholstered Furniture Construction

Before upholstery fabric is applied, upholstered furniture construction involves constructing a solid frame (usually wood), adding a spring system and then covering the furniture with padding to provide a more comfortable piece and prevent premature wear that could be caused by abrasion of the upholstery fabric against the frame.

Upholstered Furniture Frames

Traditionally, a kiln-dried hardwood frame was most desirable in ,b>upholstered furniture construction to ensure durability. Oak, maple and ash are often used when building upholstered furniture frames. More recently, frames constructed from hardwood plywood have been found to be among the most durable. Other durable materials for upholstered furniture frames include steel, plastic, strand board, softwood plywood or a combination of materials.

Furniture frame construction, especially wood frame construction, uses a variety of joinery methods, including dowels and corner blocks that have been glued and screwed together for stability. Center legs are added for support in longer pieces, such as sofas. See Wood Furniture Construction for more information on wood joinery methods.

Upholstered Furniture Springs

There are two primary spring systems used in upholstered furniture construction:

Eight-way hand-tied springs
Sinuous spring systems

Other spring systems are also used and may consist of coil steel springs or two-dimensional springs in a zig zag configuration.

Eight-Way Hand-Tied Springs

In the eight-way hand-tied spring systems used in upholstered furniture construction, three-dimensional coil springs are attached to webbing on the bottom of the sofa or chair. Then, they are tied together with twine in a series of interlocking knots to prevent individual coils from shifting out of position. Eight-way hand-tied spring systems provide even comfort. An added benefit is that the coils won’t compress to the point of "bottoming-out" the seat, no matter how heavy a load is placed on the furniture.

Sinuous Spring Systems

Sinuous springs are two dimensional, "S" shaped wires that are fastened to the top of the frame’s front rail and run from the front to the back of the furniture, spaced every few inches. Sinuous springs provide a more comfortable seat and are especially good for upholstered furniture that sits low to the floor.

Upholstered Furniture Padding

The way a frame is padded affects both its comfort and durability. Proper padding prevents the upholstery fabric from coming into direct contact with the wooden frame. Padding prevents abrasion, which could lead to premature wear of the upholstery. Cotton and poly/Dacron are the most popular frame padding materials used in upholstered furniture construction.

Seat Cushion Construction

Common materials used in upholstered furniture seat cushion construction include High density polyurethane foam wrapped in Dacron, “Spring Down”, where innerspring coils are surrounded by foam and wrapped in Dacron, and “Blendown”, which is a technique that uses a combination of down and feathers. Attached back cushions are usually filled with Dacron fiber.

High Density Foam Wrapped in Dacron

The most commonly used seat cushioning method in upholstered furniture construction is wrapping high density poly foam in Dacron to create the core of the cushion. The density of the foam and how much Dacron is used have an impact on the softness of the cushion.

Spring Down Cushioning

Spring down cushion construction involves surrounding innerspring coils with foam and then wrapping the entire package in Dacron. Once wrapped in Dacron, the cushion core is then placed inside a muslin bag before it’s upholstered.

Blendown Cushioning

Blendown cushioning is the process of combining down and feathers, wrapping them around a foam core and then inserting everything into a muslin bag before upholstery fabric is applied. Essentially, this process is the same as spring down cushioning except that there are no springs in the cushions. Of the various upholstered furniture construction methods used, blendown cushioning results in the softest cushions, but they don’t retain their shape as well as cushions constructed using the other methods discussed without periodic plumping and fluffing.

Upholstered Furniture Fabrics

A wide variety of fine upholstery fabrics are available that are constructed from natural fibers, synthetics, or a blend of both. The types of fibers used in upholstered fabrics has a direct bearing on the feel of the fabric, its durability, cleanability and resistance to fading and deterioration that can be caused by direct and prolonged exposure to sunlight. Fabrics combining a tight weave and durable fibers like nylon or polypropylene are a good choice for active use. Leather is also a popular choice for durability.

Natural Fabric Fibers

Natural fibers used in upholstery furniture fabric include cotton, wool, silk, linen and rayon/acetate. Rayon is considered a natural fiber because it is made from processed cellulose, a natural organic compound. Suede and lather are other natural materials used in upholstery.

As a rule, natural fibers have a soft feel. Continuous exposure to direct sunlight can cause cotton, linen, and even rayon/acetate fibers to deteriorate. Cotton, linen and silk may also mildew in very damp conditions.

Synthetic Fabric Fibers

Synthetic fibers are petroleum based and built to resist wear and clean easily. Although petroleum based, synthetic fiber production may still be considered an eco-friendly process because it recycles the petroleum sludge that remains after oil has been refined.

Synthetic fibers, as a class, are recognized for their durability as well as their dirt and stain resistance characteristics. Synthetics blended with natural fibers in furniture upholstery are intended to provide the best of both types of fibers. Synthetic fibers include nylon, polyester, olefin (trade name Herculon) and microfiber, an extremely fine polypropylene fiber that is less than the one denier.

Denier is a measurement that is used to identify the thickness of individual fibers of yarn or thread. Denier count is used as a measure of fabric weight, calculated by determining the weight of 9,000 meters of fabric in grams. The lower the dernier weight, the more sheer and luxuriously soft the fabric will feel.

Even though they are synthetics, nylon and olefin do not hold up well to prolonged exposure to direct sunlight.

For more information on upholstery fabrics, see Upholstered Furniture Care and Leather Furniture Care

Understanding upholstered furniture construction techniques will help you when buying furniture for your home. Gorgeous fabrics always make a good first impression, but we at Furniture From Home want our customers to know that what’s underneath the upholstery is every bit as important as the fabric when it comes to quality upholstered furniture that is sure to last a long time.