Your cabinets may be supporting a 400 lb. wall oven, your best china, or counter tops made from heavy stone. The cabinet assembly methods are very important to the life of your kitchen. Not all cabinets are made the same way. There are framed, frameless, stapled, pegged, screwed, glued, dovetailed, and even more methods to build a cabinet. I am going to share what I have discovered based upon seeing things in the field and based upon the history of furniture.
This type of assembly is a box with a face frame around it. This is the strongest method and has been used since cabinets were created. On most cabinets of this type each part will interlock with its adjoining part using some kind of improved joint (not a butt joint). In a quality cabinet, the face frame members are joined by a mortise and tenon joint (one piece has a tongue and the other has a slot to receive the tongue) glue is applied and the joint is clamped until the joint is solid. The backs, tops, sides, and floors are usually fit together in such a way that they help carry weight/stress throughout the entire box. Some add fasteners to these joints for added security. This connection if done properly is extremely long-lived, most difficult to break, and very large items can be built this way. The end panels on a quality built framed cabinet usually fit into a groove on the back side of the face frame and are usually glued into place and fastened with additional hidden fasteners. The better made cabinets may have a flush finished end joint that makes the seam virtually invisible.
Most antique furniture is framed construction, which proves the durability. Installation costs may be lowered because there are usually less cabinets required and framed custom cabinets can have extensions built-into them to allow for trimming when walls are out of square.
Think of a shoe box with no lid and you have a frameless cabinet. The box is made from four panels (two sides, top, and bottom) and a back. This is the easiest cabinet to build and the most cost affective. The ends are usually screwed or doweled together with a very simple butt joint. The “holding power” is based upon how strong the this butt joint is. Hanging this style cabinet requires everything to be installed plumb and level. If you install a cabinet out of square (often called racking the cabinet), the cabinet joints often come apart and you lose the integrity of the box. Dropping a load of dishes on the floor of a wall cabinet, house shifting, opening and closing large cabinet doors, may also cause the cabinet to “flex” and break the glue joints. Noticable gaping joints where panels connect often become visible in a short period of time causing the kitchen to look worn or old. Most styles are limited to modern concepts of full overlay doors. Inset style cabinets are not possible (see more on cabinet door styles here).
Some sales pitches about frameless cabinets are largely exaggerated to sell the product. One claim that is often pushed is that you will have more storage in a frameless cabinet. This is only true in reference to the drawer size which is the only thing affected by whether your cabinet has a frame or not. On a framed cabinet (more about framed later), the drawer box size is usually reduced by about 1 1/2″ (+/-) depending on how the cabinet is constructed. In the average kitchen, this doesn’t amount to much. Some also push the idea that you wont have a divider between double doors, but that feature is also available on most framed cabinets.