Countertop – Wikipedia, the free encyclopedia

Countertop (also counter top, counter, benchtop, (British English) worktop, or (Australian English) kitchen bench) usually refers to a horizontal worksurface in kitchens or other food preparation areas, bathrooms or lavatories, and workrooms in general. It is frequently installed upon and supported by cabinets. The surface is positioned at an ergonomic height for the user and the particular task for which it is designed. A countertop may be constructed of various materials with different attributes of functionality, durability, and aesthetics. The countertop may have built-in applicances, or accessory items relative to the intended application.

The common fitted Western-style kitchen, developed in the early 20th century, is typically an arrangement of assembled unit cabinetry covered with a more-or-less continuous countertop work surface. The "unfitted" kitchen design style exemplified by Johnny Grey may also include detached and/or varied countertop surfaces mounted on discrete base support structures. Primary considerations of material choice and conformation are durability, functionality, hygienics, appearance, and cost.

When installed in a kitchen on standard (U.S) wall-mounted base unit cabinets, countertops are typically about 25-26inches (635660mm) from front to back and are designed with a slight overhang on the front (leading) edge. This allows for a convenient reach to objects at the back of the countertop while protecting the base cabinet faces. In the UK the standard width is 600mm (Approximately 24 inches). Finished heights from the floor will vary depending on usage but typically will be 35-36" (889914mm), with a material thickness depending on that chosen. They may include an integrated or applied backsplash (UK: upstand) to prevent spills and objects from falling behind the cabinets. Kitchen countertops may also be installed on freestanding islands, dining areas or bars, desk and table tops, and other specialized task areas; as before, they may incorporate cantilevers, freespans and overhangs depending on application. The horizontal surface and vertical edges of the countertop can be decorated in manners ranging from plain to very elaborate. They are often conformed to accommodate the installation of sinks, stoves (cookers), ranges, and cooktops, or other accessories such as dispensers, integrated drain boards, and cutting boards.

Countertops can be made from a wide range of materials[1] and the cost of the completed countertop can vary widely depending on the material chosen.[2] The durability and ease of use of the material often rises with the increasing cost of the material but some costly materials are neither particularly durable nor user-friendly. Some common countertop materials are as follows:

Natural stone is one of the most commonly used materials in countertops. Natural stone or dimension stone slabs (e.g. granite) are shaped using cutting and finishing equipment in the shop of the fabricator. The edges are commonly put on by hand-held routers, grinders, or CNC equipment. If the stone has a highly variegated pattern, the stone may be laid out in final position in the shop for the customer's inspection, or the stone slabs may be selected by experienced inspectors. Emerging technology allows for virtual stone placement on a computer.[citation needed] Exact photographs can now be taken which allow for the integration of a dxf file to lay on top of an stone image.[citation needed]. Multiple slabs of material may be used in this layout process. Then the countertop assembly is installed on the job site by professionals. Commonly, initial countertop fabrication takes place at or near the quarry of origin, with blocks being sawn to thickness and then machined into standard widths (600mm and upwards), before being surface polished and edged. This method removes the need to ship waste material, and reduces the time needed to prepare client orders.[citation needed] This practice is called "cut to size" A wide range of details may be pre-machined by the fabricator, allowing for installation of different sinks and cooker designs.[3] A common drawback to natural stone is the need for sealing to prevent harboring of bacteria and/or fluids that may cause staining. In recent years oliphobic impregnators have been introduced as an alternative to surface sealers. With the advent of impregnators the frequency of sealing has been cut down to once every five to ten years on most materials. [4]

Wooden countertops can come in a variety of designs ranging from butcher block to joined planks to single wide stave. Wood is considered to be the most eco-friendly option when it comes to choosing a kitchen countertop as wood is a renewable resource.[citation needed] Wood countertops must be thoroughly cleaned and disinfected after contact with foods such as raw meat. Although the use of wooden work surfaces is prohibited in commercial food production areas in the EU, and the US Department of Agriculture advises against the use of wooden chopping boards, research by the Food Research Institute at the University of Wisconsin has shown that wooden work surfaces are no more dangerous, and in some cases safer than plastic alternatives. They have shown that while bacteria do get absorbed by the wood, they do not multiply and eventually die. While brand new plastic work surfaces are indeed easy to disinfect, once they have become heavily knife scarred they are nearly impossible to completely disinfect. This is not a problem with wooden work surfaces where the number of knife cuts made little difference.

"Postformed" (or literally "formed after being laminated" to the substrate) high pressure laminate countertop, often referred to as "plastic laminate countertop" is a material made more of wood product than plastic. The composition is of kraft paper, decorative papers, and melamine resins, bonded through high heat and pressure. This product is sometimes referred to as "Formica" or "Arborite," but these are trade names of a manufactured high pressure laminate, of which there are many manufacturers.

The postform countertop is typically a high volume factory-produced product, which accounts for the economy of the product. The material composition consists of a single thin sheet of laminate (typically .030" - .040" in thickness) that gets bonded to a 45# density particle board substrate (or other similar base material such as MDF - medium density fiberboard, or plywood), with a PVA adhesive (poly vinyl acetate - a water-based adhesive). Traditionally postform countertops were manufactured with a solvent-based contact cement (a highly flammable, volatile organic compound - VOC). However, in today's marketplace PVA adhesives have taken over for reasons of environmental responsibility (no VOC's), safety (non-combustible), economy, and strength of the glue line.

A typical system consists of the following:

1) An automated infeed system for sequencing the particle board into production. 2) The CorFab Machine, an automated feed-through machine that cuts to size, cuts and bonds build down sticks with a hot melt adhesive to the under side of the substrate, and shapes the edge detail, all in a single motion. 3) An automated laminating system that applies the adhesive to both the substrate and laminate. 4) An indexing unit that aligns the laminate to the substrate with the proper overhang. 5) A Pinch Roller that makes the bond between the laminate and substrate. 6) The Postforming Machine, that not only heats and forms the laminate around the substrate, but also cuts away the backsplash (when the top is to be used against a wall) from the main deck, all in a feed-through motion machine. 7) The AutoCove Machine, which heats and forms the backsplash upward 90 degrees, locking it into place with what is referred to as a cove stick, utilizing hot melt adhesive technology to hold it all together. 8) The final stage of the system usually consists of a trim saw that cuts the countertops to rough lengths, typically 8', 10' and 12', ready for distribution.

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Countertop - Wikipedia, the free encyclopedia