"rough sawn" refers to timber that has been cut from a log using a sawmill but has not undergone any further processing to smooth or plane the surface. This type of timber retains a coarse texture and visible saw marks, giving it a more rustic and natural appearance. Rough sawn timber is often used for structural purposes, where the appearance is not a primary concern, or in applications where a rugged aesthetic is desired. It is typically less expensive than dressed or finished timber, as it requires less processing. However, because it is not planed or sanded, rough sawn timber may require additional work if a smoother finish is needed for specific applications.

root barrier is a versatile solution designed to control and manage the growth of tree and plant roots in Australian commercial construction projects . It is a physical barrier installed in the soil to prevent tree roots from spreading into areas that can cause damage to structures, such as foundations, walls, pipes, and other underground infrastructure

See "truss"

See "pitch"

the term "ridge" refers to the highest point or the top edge of a roof where two sloping roof planes meet. It is the horizontal line that runs along the top of the roof, forming the peak or apex. The ridge is an essential component of a roof's structure, as it provides stability and support to the roof framing.

a retaining wall is a structure designed to hold or retain soil behind it. These walls are essential for managing changes in ground elevation and are commonly used to prevent soil erosion, manage water drainage, and create usable flat areas on sloped terrain. Retaining walls can be constructed from various materials, including concrete, stone, brick, timber, or steel, depending on the specific requirements of the project and aesthetic considerations.

In the context of Australian commercial construction projects, "render" refers to the application of a mixture, typically composed of cement, sand, lime, and water, to the exterior or interior walls of a building.

Reinforcing steel, commonly referred to as rebar and mesh , is a type of steel material used in Australian commercial construction projects to provide additional strength to concrete structures . It is made from a raw material called iron ore and is designed to improve the innate tension and structural strength of concrete

Reinforced concrete construction in Australian commercial construction projects refers to the use of concrete that is strengthened with embedded steel reinforcement, such as bars, mesh, or fibers, to enhance its tensile strength and overall structural integrity. This method is widely used in commercial buildings due to its durability, versatility, and ability to withstand various loads and stresses.

"reinforced" typically refers to the use of reinforcement materials to enhance the strength and durability of construction elements, particularly concrete. This is most commonly achieved through the incorporation of steel reinforcement bars, also known as rebar, or mesh within concrete structures. The reinforcement helps the concrete withstand tensile stresses, which concrete alone is not particularly strong at resisting.

regulations refer to the set of rules and standards that govern the design, construction, and maintenance of buildings and other structures . These regulations are established by the government to ensure that construction projects are carried out in a safe, sustainable, and environmentally responsible manner.

the term "Reduced Level" (RL) refers to a vertical measurement that indicates the height of a specific point relative to a predetermined reference point, often known as a datum. This datum is typically a known point of elevation, such as the Australian Height Datum (AHD), which is a standardized reference level across Australia.

In the context of Australian commercial construction projects, "rake" typically refers to the angle or slope of a surface. This term is often used when discussing the incline of roofs, ceilings, or other structural elements. For example, a "raked ceiling" would have a sloped design rather than being flat. The rake is an important consideration in construction as it affects both the aesthetic and functional aspects of a building, including drainage, structural integrity, and interior space dynamics. Understanding and specifying the correct rake is crucial for architects, engineers, and builders to ensure that the design meets both regulatory standards and the client's requirements.

a rainwater head, also known as a rainwater sump, is a component of a building's roof drainage system. It serves as a collection point for rainwater from the roof before it is directed into downpipes and subsequently into the stormwater drainage system.

a "rafter" refers to a structural component of a roof. Rafters are inclined beams that extend from the ridge or hip of the roof down to the wall plate, eave, or outer wall. They are an integral part of the roof framing system and are responsible for supporting the roof deck and its associated loads, such as roofing materials, insulation, and any additional weight from snow or maintenance activities.