Oil Panning: A Creative Photography Technique Explained

Oil canning is a common issue in metal roofing and panelling, characterised by a rippled or wavy appearance in the flat areas of the material. It is a natural occurrence in cold-rolled metal and does not indicate any structural issues. While it may be unsightly, it is purely an aesthetic concern and does not affect the functionality or integrity of the metal. Oil canning can be influenced by various factors, such as thermal expansion and contraction, installation methods, and the colour and finish of the metal. To minimise its appearance, certain measures can be taken during manufacturing, installation, and through design choices.

Characteristics of Oil Canning

Oil canning is a natural occurrence in sheet metal products, causing them to bow or wave outwards

Oil canning is a common issue with sheet metal products, causing them to bow or wave outwards. It is a natural occurrence and is considered a cosmetic issue that does not impact the structural integrity of the product. Oil canning typically affects flat metal panels and is characterised by a wrinkled or wavy appearance. It is most noticeable on darker and glossier finishes, as well as when sunlight reflects off the irregular surface.

Oil canning is caused by stress on the metal, which can occur during the milling and manufacturing processes, as well as during installation and assembly. One of the main causes is the expansion and contraction of metal due to temperature changes. When metal panels are restricted at the edges, they are unable to expand and contract freely, resulting in the oil canning effect. Other factors that can contribute to oil canning include overtightened fasteners, uneven substrates, settling of the structure, and mishandling of metal panels during storage and transportation.

While oil canning cannot be completely prevented, there are measures that can be taken to minimise its appearance. Using heavier gauge metal, corrugated panels, or panels with stiffening ribs and striations can help to disguise the effect. Lighter-coloured panels and matte finishes can also make oil canning less noticeable. Proper installation techniques, such as following the manufacturer's handling instructions and ensuring a level substrate, are crucial in reducing the occurrence of oil canning.

It is important to note that oil canning is not a structural issue and does not affect the functionality or longevity of the metal product. However, it can be a concern for building owners from an aesthetic standpoint. Therefore, it is recommended to consult with manufacturers and take preventative measures during the product selection and installation phases to minimise the occurrence of oil canning in sheet metal products.

It is caused by factors such as thermal expansion, fastening and installation, and the settlement of the structure

Oil canning is a visual phenomenon that makes metal panels look wavy or distorted, especially in the broad, flat areas of a metal roof or wall system. It is an inherent characteristic of light-gauge, cold-rolled flat metal products. While oil canning does not affect the structural integrity of the panel system, it can be unsightly and may require replacement if severe.

There are several factors that can cause oil canning, including:

Thermal Expansion

Thermal expansion occurs when metal panels are subjected to temperature changes, causing them to expand and contract. This can be more pronounced in certain climates or during specific times of the year. The waviness of oil canning may be more noticeable when the metal is heated by the sun.

Fastening and Installation

Improper fastening and installation practices can also lead to oil canning. This includes over-driving fasteners, angling fasteners, and incorrect usage, handling, and storage of panels by installers. It is important to follow the manufacturer's recommendations for handling and installation to minimize the risk of oil canning.

Settlement of the Structure

Oil canning can occur due to structural changes in the building, such as settling or extreme weathering, that cause tension or stress on the metal panels. This can be more common in older buildings or those subjected to extreme weather conditions.

Oil canning does not affect the structural integrity of the product but is a cosmetic issue

Oil canning is a phenomenon that can occur with metal roofing and wall panel systems, causing them to appear wavy or distorted. While it may be undesirable from an aesthetic standpoint, oil canning does not affect the structural integrity of the product. It is simply a cosmetic issue that does not impact the functionality or longevity of the panels.

Oil canning is an inherent characteristic of light-gauge, cold-rolled flat metal products, particularly those with broad, flat areas. It is often referred to as stress wrinkling and can occur with various construction materials such as steel, aluminium, zinc, and copper. The severity of the waviness can vary depending on factors such as colour, finish, time of day, season, and viewing angle.

Although oil canning does not pose any structural concerns, it is important to understand its causes to implement effective prevention and mitigation strategies. Oil canning can occur during the production process if the metal sheets are not processed evenly, leading to ripples or waves in the panels. It can also be caused by improper installation, such as insufficient space for thermal expansion and contraction, rough handling, or excessive fastening.

To minimise the appearance of oil canning, several measures can be taken. Using heavier-gauge metal, narrower panel widths, and low-gloss or matte finishes can help reduce the visibility of waviness. Additionally, incorporating rib rollers or stiffening ribs can add aesthetic appeal and enhance the structural integrity of the panels while also disguising potential oil canning effects.

While oil canning cannot be completely avoided, following best practices in material selection, installation techniques, and preventative measures can help reduce its occurrence and improve the overall appearance of metal roofing and wall panel systems.

It can be minimised by using heavier gauge panels, installing panels with striations, and ensuring proper installation procedures

Oil canning is a visual phenomenon that makes metal panels look wavy or distorted, especially in the broad, flat areas of a metal roof or wall system. It is an inherent characteristic of light-gauge, cold-formed metal products with broad, flat areas. While it does not affect the functionality of a roof panel, it is an unwanted aesthetic issue.

Oil canning can be minimised by using heavier gauge panels, installing panels with striations, and ensuring proper installation procedures. Here are the details:

Using Heavier Gauge Panels

A heavier gauge metal is stronger and harder to bend, which makes it better equipped to prevent oil canning. The lower the gauge number, the thicker the panel. For example, a 22-gauge panel is thicker and less likely to have wrinkles than a 26-gauge panel. Thicker metal is harder for the metal to give in and move, reducing the waviness associated with oil canning.

Installing Panels with Striations

Striations are a pattern of linear grooves on the flat surface of the panel, running parallel to the standing seam. They are an effective way to disguise potential oil canning as they break up the amount of flat surface, making the waviness less apparent. Striations are located throughout the entire panel, making it hard for the waviness to be apparent. They are often recommended for maximum durability and do not increase the cost of the panels.

Ensuring Proper Installation Procedures

Proper installation procedures are crucial in minimising oil canning. This includes following the manufacturer's handling and installation instructions, ensuring a level and flat substrate, and correctly installing fasteners. Installers should carry and support panels properly during transport and installation, avoiding twisting and damage. Fasteners should not be over-driven or installed at an angle, as this can create unnecessary stress on the panel, leading to oil canning.

Oil canning is more visible on darker colours and glossy finishes

Oil canning is a phenomenon that causes metal panels to appear wavy or distorted, particularly in their broad, flat areas. While oil canning does not affect the structural integrity of the metal, it is often considered undesirable from an aesthetic standpoint.

The visibility of oil canning is influenced by various factors, including colour and finish. Darker colours tend to accentuate the flaws caused by oil canning, making them more noticeable. Lighter colours, on the other hand, can help reduce the visibility of these imperfections. Similarly, glossy finishes can increase the visibility of oil canning, whereas matte or low-gloss finishes can help to disguise it.

The reason darker colours make oil canning more visible is that they create greater contrast with the surrounding environment, making any waves or distortions more apparent. Lighter colours, on the other hand, tend to blend more seamlessly with the surroundings, helping to minimise the appearance of flaws.

Additionally, glossy finishes reflect light in a way that can emphasise the unevenness of the surface, making oil canning more noticeable. Matte or low-gloss finishes, by contrast, absorb light and create a smoother appearance, reducing the visibility of imperfections.

While colour and finish are important factors in the visibility of oil canning, other elements also play a role. These include the angle of viewpoint, time of day, and type of metal. Additionally, the installation process can significantly influence the occurrence and visibility of oil canning, with proper techniques helping to minimise its effects.

Frequently asked questions