Lath art is a form of woodworking folk art for making rustic pictures out of strips out of old “lath” from “plaster and lath” walls. Today it is commonly made from lattice, lumber stickers and weathered lobster traps. Beach scenes and rural scenes are the most popular themes.
Lath art is the traditional matrix for fresco painting; the pigments are applied to a thin wet top layer of plaster and fuse with it so that the painting is actually in coloured plaster. In the ancient world, as well as the sort of ornamental designs in plaster relief that are still used, plaster was also widely used to create large figurative reliefs for walls, though few of these have survived.
Lath art may be used to create complex detailing for use in room interiors. These may be geometric (simulating wood or stone) or naturalistic (simulating leaves, vines, and flowers). These are also often used to simulate wood or stone detailing found in more substantial buildings.
In modern days Lath art is also used for False Ceiling. In this, the powder form is converted in a sheet form and the sheet is then attached to the basic ceiling with the help of fasteners. It is done in various designs containing various combinations of lights and colors. The common use of this plaster can be seen in the construction of houses. After the construction, finer layers of plaster are added on top of the plasterboard to give a smooth brown polished texture ready for painting.
Many of the greatest mural paintings in Europe, like Michelangelo’s Sistine Chapel ceiling, are executed in fresco, meaning they are painted on a thin layer of wet plaster, called intonaco; the pigments sink into this layer so that the plaster itself becomes the medium holding them, which accounts for the excellent durability of fresco. Additional work may be added a secco on top of the dry plaster, though this is generally less durable.
Lath art is a far easier material for making reliefs than stone or wood, and was widely used for large interior wall-reliefs in Egypt and the Near East from antiquity into Islamic times (latterly for architectural decoration, as at the Alhambra), Rome, and Europe from at least the Renaissance, as well as probably elsewhere. However, it needs very good conditions to survive long in unmaintained buildings – Roman decorative plasterwork is mainly known from Pompeii and other sites buried by ash from Mount Vesuvius.
A lath or slat is a thin, narrow strip of straight-grained wood used under roof shingles or tiles, on lath and plaster walls and ceilings to hold plaster, and in lattice and trellis work.
Lath has expanded to mean any type of backing material for plaster. This includes metal wire mesh or expanded metal that is applied to a wood or metal framework as matrix over which stucco or plaster is applied, as well as wallboard products called gypsum or rock lath. Historically, reed mat was also used as a lath material.
One of the key elements of lath, whether wooden slats or wire mesh, are the openings or gaps that allow plaster or stucco to ooze behind and form a mechanical bond to the lath. This is not necessary for gypsum lath, which relies on a chemical bond.
Plaster is a building material used for the protective and/or decorative coating of walls and ceilings and for moulding and casting decorative elements.
Lath and plaster walls have several benefits, including fire and mold resistance, soundproofing, and heat insulation. Though wooden lath can be susceptible to mold growth and decay, metal lath covered in plaster creates an environment that is inhospitable to toxic molds. Metal lath and plaster walls can be twice as resistant to fire than drywall, and are capable of achieving fire rating with a thick assembly of plaster and lath can also achieve the same decibel rating as of drywall.
Lath art has a lot in common with marquetry and intarsia. They are all woodworking hobbies to make pictures out of sections of wood, but marquetry and intarsia use the wood grain as a design element, and lath art uses the direction of the lath stick and the colors of the stains as a design element.
Keys are formed by plaster that oozes through the spaces or gaps between wooden lath, or the holes in metal lath, and around to the lath’s backside. This secures the plaster to the lath by creating a sort of hook. Wooden and metal lath depend on the mechanical bond created by keys to adhere the plaster to the lath.
Lath can be attached directly to the fame of a building, such as the studs of a wooden structure. Alternatively, lath can be attached to a wooden or metal frame called a furning, which is then attached to the building structure. Furnings are often used in masonry construction. Frames are also used when using lath and plaster to create decorative, curved, or ornamental work.
Lath art may be cast directly into a damp clay mold. lath may be used to produce clay productions, which when fired in a kiln become terra cotta building decorations, or these may be used to create cast concrete sculptures.
Plaster expands while hardening then contracts slightly just before hardening completely. This makes plaster excellent for use in molds, and it is often used as an artistic material for casting. Plaster is also commonly spread over an armature (form), made of wire mesh, cloth, or other materials; a process for adding raised details. For these processes, limestone or acrylic based plaster may be employed, known as stucco.
Wooden laths are narrow strips of straight-grained wood depending on availability of species in lengths of from two to four or five feet to suit the distances at which the timbers of a floor or partition are set.
The thicker laths should be used in ceilings, to stand the extra strain (sometimes they were doubled for extra strength), and the thinner variety in vertical work such as partitions, except where the latter will be subjected to rough usage, in which case thicker laths become necessary.
Laths were formerly all made by hand. Most are now made by machinery and are known as sawn laths, those made by hand being called rent or riven laths. Rent laths give the best results, as they split in a line with the grain of the wood, and are stronger and not so liable to twist as machine-made laths, some of the fibers of which are usually cut in the process of sawing.
Laths must be nailed so as to break joint in bays three or four feet wide with ends butted one against the other. By breaking the joints of the lathing in this way, the tendency for the plaster to crack along the line of joints is diminished and a better key is obtained. Every lath should be nailed at each end and wherever it crosses a joist or stud. All timbers over three inches (76 mm) wide should be counter-lathed, that is, have a fillet or double lath nailed along the centre upon which the laths are then nailed. This is done to preserve a good key for the plaster.
Walls liable to damp are sometimes battened and lathed to form an air cavity between the damp wall and the plastering.
Lathing in metal, either in wire or in the form of perforated galvanised sheets, is now extensively used on account of its fireproof and lasting quality. There are many kinds of this material in different designs, the best known in England being the Jhilmil, the Bostwick, Lathing, and Expanded Metal lathing. The two last-named are also widely used in America.
Lathing nails are usually of iron, cut, wrought or cast, and in the better class of work they are galvanized to prevent rusting. Zinc nails are sometimes used, but are costly.