A Guide to Australian Roof Types

What are Eaves and why are the needed?

Eaves are the part of the roof that hangs out over the walls to provide shade to the outside of your house. An eave is formed when the ends of the rafters extend past the outside walls and hang over the side of the house.

Eaves are made up of two main portions: the fascia and the soffit. The fascia is a board that runs around the building horizontally, beneath the eaves, to cover the ends of the roof’s protruding rafters. The soffit is the panelling which forms the underside of the eaves.

When they refer to pitch on a roof what does that mean?

Roof pitch is one of the most visible aspects of a roof. It’s the measure of the steepness of a roof, or its slope.

Is there a maximum or minimum roof pitch required for Australian residential housing?

For corrugated iron roofing, the ideal minimum pitch for Australian residential housing is 5 degrees. Having a pitch under 5 degrees has severe limitations. For tiled roofing, the minimum pitch for Australian residential housing under Australian Standards is 15 degrees.

Roof Truss systems explained.

Basic terms: Supportive framework, usually consisting of rafters, posts and struts, that holds up a roof.

Skillion Roof Explained

Skillion roofs only have a single flat surface, as opposed to having two sloping sides which meet in a ridge or peak in the centre of a building.

The difference between a standard flat roof and a skillion roof, however, lies in the steepness and pitch. The skillion roof has a significantly steeper and more noticeable pitch.

What is a Gable Roof?

A traditional gable roof can be recognized by the symmetrical triangular shape created at the top of the building by two roof panels. These two roof panels should be pitched so they meet in the centre of the building in a ridge.

Can you explain a Raked Ceiling and some of the features and benefits?

A raked ceiling is an inclined ceiling that provides extra height than an ordinary ceiling does. Raked ceilings may also be called a vaulted ceiling or a pitched ceiling.

Features and benefits include:

Open plan large space. With a raked ceiling, the sense of light and space will be drastically improved in comparison to a flat ceiling residence. Raked ceilings means more space for windows which allows more advantages of natural light.

Raked ceilings provide additional internal airflow, especially in hot summer months, giving the air plenty of room to move.

-Raked ceilings give the impression of increased space that gives more aesthetic freedom for furniture and accessories.

Raked ceilings have a precise form of craftmanship which makes the residence stand out from the rest. This has possibilities to increase resell values.

What is colorbond made from?

Colorbond material is a lightweight and sturdy steel base coated with high-quality paint. The steel based is made of galvanized steel, meaning it is treated with zinc substrate that is attached to the steel by the use of electrodes and current. This steel base is then treated with anti-corrosion and weather-resistant paint which makes Colorbond the ideal material for Australian conditions and climates. Colorbond material is also created by the process of cold reduction. This means that the hot rolled coil steel is cleaned by the use of acid and then pressed with rolls. The result is stronger and thinner steel.

What is the standard and or recommend depth of an eve in Australia?

As a rule of thumb, eaves width should be 45% of the height from the window sill to the bottom of the eaves.

  • 450mm where height is 9001200mm
  • 600mm for a height of 12001350mm
  • 900mm for a height of 13502100mm
  • 1200mm for a height of 21002700mm.

What is Barge Capping?  

Barge Capping provides an aesthetically appealing finish and provides a watertight seal on gable roof ends.

What are vaulted ceilings and what are the features and benefits?

Vaulted ceilings are self-supporting arches above walls and beneath a roof. Vaulted ceilings extend a typical flat ceiling to take advantage of unused roof structure space.

Features and benefits include:

  • They offer a sense of spaciousness.
  • They allow for bright natural light for tall           windows or skylights.
  • They occupy otherwise wasted attic space.
  • They are aesthetically pleasing. An eye catching benefit for living.

Timber trusses V.S. prefabricated rafters

It is advisable to choose rafter roof structure if the building is smaller than 6 meters. For example, if you want to increase your living space or build a house extension. 

Open Gable Roof Explained

Open gable roofs have a triangular extension at each end of the house, with the roof section un-boxed and exposed at the end.

Box Gable Roof Explained

Box gable roofshave a triangular extension at each end of the house, with the roof section boxed at the end. This design is extremely similar to the standard gable roof, but distinguishes the triangular section of the design more. This is a variation of a gable roof.

Dutch Gable Roof Explained

A dutch gable roof is a hybrid of a gable and hip roof. The typical design composes of the gable roof being placed on top of the hip roof, providing more space within the loft. This is a popular design with many property owners,adding an enhancing aesthetic appeal to a house as well as providing the practical function of added space. This is a variation of a gable roof.

Pyramid Hip Roof Explained

pyramid roof is a type of hip roof that has four sides that are all triangle shaped and all slope downward. They are built onto a square or rectangular frame. Pyramid roofs are a popular choice for a shed, gazebos, and summerhouses.

Dormer Roof Explained

A dormer roof is more an addition to an existent roof. It is a window and a roof (gabled, hipped, flat, among others) protruding from the existing slope of the roof. A functional dormer creates usable space out of the roof, adding natural light and headroom.

Shed Roof Explained

A Shed roof is similar to a flat roof but has more pitch, it is frequently used for additions or with other roof styles. A shed roof has asingle slopethat can vary in steepness depending on the design.

Gambrel Roof Explained

A Gambreal Roof is a multi-sided (polygonal) hip roof with steeply pitched slopes that rise to a peak.It is a roof design with 4 sides instead of 2 sides. It has theappearance of a slopedroof, but the slope of the top sides are not as steeply sloping as the bottom sides.

Saltbox Roof Explained

A saltbox roof is a gable roof with asymmetrical planes, one long and one short side. The short side typically has a low slope, while the long side has a steepslope. This is a variation of a gable roof.

Butterfly Roof Explained

A butterfly roof is formed by two adjacent gables sloping inward toward the middle, so that they dip to create a central valley. Butterfly roofs are ideally designed for the purpose of capturing rainfall in the central valley of the roof between the inward facing slopes.

Hip & Valley Roof Explained

A hip & valley roof is simply a modified or extended hip roof. The shape and pitch of the surfaces are basically the same, however the base shape changes from a simple rectangle to a ‘T’ or ‘L’ shape, on plan.

Clerestory Roof Explained

A clerestory roof is a roof with a vertical wall which sits between the two sloping sides, which features a row of windows (or one long, continuous window).

Lean-To Roof Explained

A lean to roofis defined as single slope roof with its upper edge adjoining a wall or building. A lean to roofdesignis one of the simplest ways to connect the addition to an existing building.They are also a popular choice for adding shade and screening to a porch, or when designing a carport.

Curved Roof Explained

A curved roof is essentially a roof that has a curved shed-style shape. Curved roofs are a fairly new roof design that focuses on aesthetics more than durability.

What is the ideal length of roof eaves that face north in the summer?

As a rule of thumb, all roof eaves length should be 45% of the height from the window sill to the bottom of the eaves.

  • 450mm where height is 9001200mm
  • 600mm for a height of 12001350mm
  • 900mm for a height of 13502100mm
  • 1200mm for a height of 21002700mm.

Having the length of a roof eave in accordance to the suitable distance between the window sill and bottom of eaves (shown above), will ideally shade summer heats and let in winter heats.

The most ideal roof system for northern summer suns, is a gable roof with 600mm eaves facing north.