Lath

Laths are usually thin wooden strips that are used to attach plaster to ceilings and to frame partitions. It refers to any form of supporting material placed under roof shingles or tiles, on walls and ceilings to hold plaster.

A significant feature of it, whether they are wooden slats or wire mesh, are the openings or gaps that allow plaster or stucco to flow behind and when the plaster sets, they are bonded to the lath.

Types of Lath

Wood Slat Lath

In building construction, this material are used to form a framework for plaster to attach to. There were three ways of making it for plaster:

1. Wood that is traditionally split with the grain from hardwoods like chestnut & oak, or from softwoods like eastern white pine and riven and nailed in place are known as riven lath;

2. Thin, sawn boards which are partially split with an axe and the splits pulled apart to form gaps for the plaster to flow into are called accordion laths.

3. With the invention of the circular saw in the early 19th century, lath was sawn in sawmills and then delivered to the building site.

 

wooden lath

Applications

● The coverings on roofs and walls (i.e tiles & slates) are fixed to laths and they are called battens or slats

● The wooden strips are used to form lattice­ work

● The bars of venetian blinds and window shutters

● It is also used on many tobacco farms as a means to carry and hang the plant in barns by hooking or spearing Metal Lath

Popularly used with plaster and stucco in homes and commercial buildings. The lath provides a matrix for the plaster or stucco to attach and this adds strength and rigidity to the structure.

It is made by slitting and pulling apart a sheet of metal so it is expanded or by welding or weaving wires together and theses are are painted or galvanised to prevent corrosion.

 

lath7

Types of common Metal Laths

● Expanded metal lath is where the slitting & expanding of a thin sheet of metal produces diamond shape holes

● Ribbed lath is where the slitted and expanded metal forms V­-shaped ribs, making it more rigid 

● Wire lath is a welded or woven wire lath

● Paper backed wire lath is a wire type with a building paper attached

● Self­-furring lath is an expanded metal type which is dimpled to hold itself off from a solid surface

Gypsum Lath

This type consists of gypsum plaster that is sandwiched between two sheets of absorbent paper. The finish side is treated with gypsum crystals for the chemical bonding of the plaster and or it is sometimes punctured so that mechanical bonding can take place.

It has replaced wood lath in many instances because of its ease of usage, gives better results and is non­-combustible. It is available with a foil cover which acts as a vapour barrier and also as a heat reflector.

 

gypsum lath