Use kiln-dried Alder or Oak for frames. Both woods are hardwoods from planned-growth American timber farms. They should be milled into at least 4/4” pieces of lumber before drying. For joining and blocking a variety of hardwoods and hardwood laminates are fine. Most joints are blocked, screwed, glued, and fastened for stability. Additional horizontal supports between the arms of each sofa minimize any twisting during moves.
- Spring Systems
Once the frame is constructed, a spring system is installed to support the seating area. Good furniture manufacturers will offer two different types of spring support systems: Standard Springs and Eight-Way Hand Tied Springs. When the spring system is finished with a top layer of padding, it is commonly called the “seat deck”.
Standard Springs provide good support at a good price. Most manufacturers offer either Sinuous Springs or Drop-In-Springs as their standard, depending on how they make their furniture. Both types affix to the frame to support the seat deck. Standard springs have a formal, very firm “sit” and only move in the up/down direction. Compare that motion to eight-Way Hand-Tied Springs, which move in many more directions.
- Sinuous Springs are heavy-gauge steel springs that have been heat formed into continuous “S” shapes. They are cut into lengths and affixed to the frame. Drop-In Springs are mass-manufactured welded units that are not appropriate for good furniture. Avoid them.
Eight-Way Hand-Tied Springs have a wide range of movement providing a very even and individual sit because they move up and down and side to side. This craftsman process individually ties heavy gauge coils front to back, side to side and diagonally (eight ways) to provide the highest level of quality, comfort and durability. This process costs more because it is time consuming and can only be done by hand.
- Cushions, Pillows, Padding, and Fills
When a piece of upholstered furniture has its frame and springs, the next components are the cushions and padding. Seat Cushions sit on top of the spring system and seat deck. Back Pillows, if present, rest against the back and arms of the piece. Whether you’re looking for overstuffed, sink-into comfort or a more formal sit, pay special attention to this section.
Most cushions are made of a high-density Dacron® foam core that is then wrapped with either soft polyester, feather and down, or a hypoallergenic down substitute. Dacron adds resilience so that pillows and seats keep their shape, while the wraps form a soft envelope. Cushions and pillows should be sewn into cotton cases to ensure smooth upholstering.
Feather and Down offers the maximum comfort and softness in cushions and pillows that most people desire and designers prefer. Feather and Down back pillows and wrapped seat cushions can always be “fluffed-up” to maintain an attractive look. Feather and Down fills and wraps require a little more maintenance than polyester and high density-foam but they have greater comfort, durability and resilience. Padding helps any piece of furniture to feel substantial and comfortable.
The textile should be applied over soft, ample padding of high-density foam and/or polyester to create a tight, tailored line where it wraps around the frame. Beware of lumpy upholstering and places where you can feel the frame wood through the textile; they are signs of inferior work.
- Fabric and Leathers
Textiles, a term used in the furniture industry, encompass both Fabrics and Leathers. Textiles can account for up to 70% of furniture price, but more expensive does not necessarily mean better or better wearing. So, you should carefully consider how you will use each piece of furniture and which textile is best. Determining these answers goes a long way towards your satisfaction.
Tightly woven fabrics and blends tend to wear longer than light or loose-weave natural fibers.
Leather is a beautiful, durable and easy-care natural material that gets softer and better with time. To create beautiful leather, top-grain hides are tanned, processed and dyed to give a certain color or look. Tanning refers to the process in which salts are used to cure the hide and to stabilize its shape. Dying refers to infusing the hide with different color dyes.
Aniline dying is a 1st quality process that imparts color but doesn’t disguise the beautiful, natural character of the hide. Some leathers are further treated with a pattern, texture, or polish.
Because leather is a natural product, there may be some normal variation between hides. Leather is a very sturdy material, but it, too, will need frequent vacuuming and cleaning to preserve its finish and beauty.
Go on to read about Size and Care of Upholstered Furniture.