A cornice is a decorative moulding along the top edge of a building or furniture element.

A cornice protects your home from excess water and sunlight and break up large expanses of the wall surface. Cornices can be found on many different buildings, such as modern homes, cathedrals, mosques, schools, theatres, and other structures. Unlike skirting boards that are found at the bottom, this architectural feature is found at the top of the wall. Cornices are made of materials like wood, stone, stucco medium density fibreboard or metal. A simple cornice can be formed using a crown. This process is called crown moulding. However, crown mouldings are not considered cornices unless it hangs over a window or vent.

Advantages of a cornice

The architectural detail of these design elements offers more than just their decorative aspect. They also have useful functions. The function of a cornice is to protect the exterior walls, fascia boards and roofing from weather elements. For example, a projecting cornice helps in throwing rainwater free of walls. However, you can use an interior cornice for interior walls. Most cornices are crucial in preventing water damage, leading to other problems such as mould building up over time. Additionally, crown moulding enhances the style and look of the exterior structure. They also provide contrast with trim underneath them or bricks above them. The ornamental design of a cornice can help to achieve an overall balance and consistency in the architectural style throughout the building.

Different types of cornice

There are different cornice types that vary in size, shape and scope depending on how elaborate they need to be. An example is the architrave cornice and the bracketed cornice. They also vary depending on whether it is for residential building or a commercial building. These can be interior cornices or exterior cornices and many installed with either cement or compound. There are three main types ; a box cornice, open cornice or closed cornice. Below is a brief list of the most common shapes and styles:

House eaves (overhang)

A projecting cornice that only extends over part of the wall rather than covering its entire surfaces like other cornices such as dripcornice, bargeboard, or raking-cornice. Roof eaves are an important inclusion for functionality and style.

Simulated or false bracket

A cornice that has the appearance of supporting elements but is actually decorative in nature. They are usually made of moulded wood or pressed metal and resemble actual timber brackets.

Drip cornice

A feature along the edge of a roof to protect it from water run-off which extends beyond the wall surface by approximately 2" to 4".

Ogee (rafter)

A type of cornice line where each section is shaped like an S curve to create the impression of an ogee archway.

Other types of roman architecture cornices include: a box cornice, soffit, jockey, gable, cavetto cornice and garret, among others, depending on their function and scope.

How do you install a cornice?

Although the design and installation may vary slightly depending on your chosen material, there are several steps you can follow and techniques to keep in mind:

Measure the length of the eave or soffit so that you know how much moulding you need. You can add an additional amount when cutting for mistakes or wastage.

Cut one piece of moulding at a time by using a table saw with a fine blade to ensure accurate measurements and clean cuts. For curved sections such as ogee, use a band saw instead.

To protect the wood from splitting, drill holes in it before screwing into place or use nails that fit snugly in the holes and butt up against the edge of the board. You may even consider using masonry adhesive or cornice cement for installation.

Use a level to ensure that each piece is flat and parallel to the others, so you get an even final result.

Measure and mark any locations where you need to fit in wiring, plumbing or HVAC ducts, so the cornice does not cover them. Cut holes through it using a rotary tool or jigsaw for them to fit in snugly.

Fit in all pieces of moulding, ensuring they line up with one another at corners and intersections before driving screws into place from behind.

What is the purpose of a cornice?

The purpose of a cornice is to enhance the look of your exterior design. Cornices can come in many different styles and shapes depending on your preference and the overall architecture of the building. Many architects use cornices when designing homes or commercial buildings because they serve an aesthetic purpose and also protect the structure against rain, hail, snow, wind damage, etc. Due to weather elements, they are often made out of sturdy materials such as wood or metal to last for years without wearing down or breaking apart.

What is the difference between a cornice and an eave?

Cornices are overhanging elements that only extend over part of the wall, while eaves cover the entire surface of a roof. In many cases, eaves will also extend past the side of a house as well as above it. Cornices can be square or rectangular in shape or consist of smaller components such as mouldings or coils, which make up a more ornate design. They play an important role in protecting walls from weather elements such as rain which can cause damage to brickwork and other stone materials. Eaves do not provide this type of protection.

What is the purpose of moulding?

Mouldings are decorative elements that can be used on many types of surfaces. The main purpose of moulding is to give something an aged, elegant yet ornate look depending on the type and style you use for them. They can come in all sorts of shapes, such as square or circular ones, each with its own unique characteristics. The two main reasons architects often use mouldings when designing homes or any other structure have to do with.

Protection

Mouldings protect other elements like eaves and roof edges against water damage and rust formation.

Aesthetics

Cornices and mouldings help enhance the overall design of a house by adding an attractive finishing touch to the look of any wall.

What is a cornice made out of?

There are many different types of materials that can be used to create mouldings, each with its own unique characteristics. The most common material is plaster or plasterboard, which is inexpensive and easy for professionals to install on exterior walls of homes or other buildings. Wood also makes for a popular choice thanks to its sturdiness and often comes pre-painted in white colour, so it blends into the building's design without looking too conspicuous.

Can you paint over a cornice?

Yes, it is possible to paint over a cornice as long as you first take the necessary steps to ensure that water does not seep behind the moulding and cause damage to the bricks or stone material. The best way to do this is by applying a coat of waterproof sealant first to create a barrier between the paint and other elements. Once dry, apply at least two coats of exterior house paint or any colour you choose. The base coat often hides the cornice cement.

Interested in a career in designing or building cornices? Take a look at the training.gov.au website.