Home Lighting Design
Lighting is the forgotten hero of home design – when done well it makes us feel good, and our homes safe and easy to navigate, but it can also be energy hungry. Interior designer Megan Norgate suggests ways to make clever lighting choices that look great and have less impact.
Lighting accounts for an average of 6 per cent of residential energy use and between 8 and 15 per cent of the overall household electricity budget. There are clearly efficiency and budgetary gains to be made when designing and specifying lighting solutions. Despite this, home lighting choices are often an afterthought, missing the opportunity to maximise efficiency and to
access the potential health, functionality and aesthetic benefits of good lighting design.
Each area of a home has different lighting requirements and each light fitting need only provide enough directional light for its purpose. The earlier that lighting is addressed in the design and build process, the more likely sustainable and appropriate choices will be made before time, patience and budget run out.
DAYLIGHT AND PEOPLE
The most important source of light to consider is daylight, not only because it is a free resource, but also because it positively affects our health and happiness. Ideally a home has enough windows that supplementary lighting is rarely needed during daylight hours, as this causes the least disturbance to human circadian rhythms. Circadian rhythms are the biological, behavioural and cognitive changes that occur in the body over a 24-hour period in response to environmental signals such as light and darkness. Natural light can assist in reducing fatigue and improve sleeping patterns, alertness and mood.
Appropriately sized and oriented windows will allow light gain according to the direction and timing of sunlight. For example, east-facing windows can be lovely in bedrooms and kitchens to help you start the day, and larger windows are needed in daytime use areas such as kitchens and living areas than in bedrooms and utility spaces. Though of course, window sizing and orientation for daylight should be considered within passive solar design requirements to balance against undesired heat gain or loss. In a dimly-lit environment, the placement of new windows, skylights or solar tubes can have multiple benefits. When there is overshadowing from a neighbouring property, boundary wall or vegetation, a clerestory or highlight window can dramatically improve an interior space. Alternatively, quality skylights with seals, double glazing and a capacity for summer shading can be used. Solar tubes effectively access natural light with a small glazed surface area, preventing the heat gain and losses associated with skylights.
Other, often less expensive tactics include painting the shaft or light well a light colour to bounce light into the interior, or using light paint and reflective surfaces on south-side exterior fences or walls to bounce light back through south-facing windows. For apartments or other spaces with no roof or wall access to daylight, LED skylights that mimic the outdoor light levels could be a good option.
PLANNING YOUR LIGHTING
A considered lighting plan begins with working out what tasks are likely to be done in a particular space, and the amount of lighting required to comfortably complete them. This means considering the ways householders use each room; if people sometimes work at the dining table, then an option for bright light is a good idea. Even better, place a window or skylight above daytime work areas to boost productivity.
Lighting throughout a house can be provided by a combination of ceiling lights, wall lights, downlights and pendants. Some areas of the home, such as utility areas and passageways, have fixed layouts but bedrooms, living rooms and dining rooms have movable elements, so a degree of flexibility can be incorporated, including the use of standard and table lamps. In open plan designs, flexible lighting can help to define zones and allow for differing moods and activities
Task lighting is needed in utility areas such as kitchens, laundries, bathrooms and offices. Here it can be directed where it is needed most, such as above the sink, stovetop and food preparation areas, ensuring a person’s head will not cast a shadow. LED strip lights and recessed downlights under cabinets are ideal for these purposes, and should be specified before cabinets are built and installed so that recessed tracks, cutouts and transformers can be integrated into the design.
Outdoor lighting is important for safety and amenity, but don’t overdo it, and make sure directional lighting doesn’t face a neighbour’s window or entranceway. Floodlights can use up to 500 watts per light and can easily be left on accidently during the day, so using LEDs could save around 80 per cent of energy use. Wall-mounted lights, solar lighting and porch lights are a welcoming safety feature around access areas. Outdoor living and dining spaces can also benefit from ambient lighting, such as a pendant or solar powered fairy lights strung over pergolas or fences. Various landscape, deck and pathway lighting can be used for safety and effect; pick a couple of key areas to highlight rather than the whole space.
HOW MUCH LIGHT?
To assess the quantity of light needed in an area you need to consider both quantity of light emitted (lumens) and the beam angle (60-180 degrees). Lux is the measurement of light intensity, based on lumens, distance from the light source and the beam angle of the light. This measurement is used to ascertain how many of each type of light is needed in a particular area of your home. Typically for general use, 200 to 300 lux is sufficient, with 350 to 800 in task areas and 150 lux for soft light. Free software such as Relux can be used to calculate how many light fittings are needed in each space, or lighting designers and some suppliers will be able to provide an accurate plan.
LIGHT TEMPERATURE AND COLOUR
Colour temperature is a way of defining the colour characteristics of light, ranging from cool, bluish tones to warmer, yellow and red ones. Task areas are often best served with a ‘white’ light at the cool end of the spectrum for a given globe wattage, as cooler LED lights tend to have slightly higher lumen outputs per watt of electricity used. Studies have shown that blue light can have a stimulating effect on people due to its similarity to early morning light. Spaces for relaxation may benefit from warmer light sources for the opposite reason. Avoid placing very warm and cool lights next to each other as they can clash. Some fittings and bulbs have both warm and cool LEDs and smart control systems, allowing the flexibility to select the colour temperature desired using a remote control or mobile phone app.
Home automation uses technology to control homes with the push of a button, voice command or our presence in a room. At a basic level it is a sensor light that switches on with human activity. More sophisticated systems allow lighting and appliances to be controlled via smartphones or tablets. These products allow users to schedule appliance and lighting use and get alerts when something has been left on. Home automation is best approached by starting small and understanding the technology fully before investing.
A LUME-INATING DESIGN
Lighting was a carefully considered aspect of this new house design by Lume Architecture in Eltham, in outer, leafy Melbourne. Architect Lynnsay Prunotto used a furniture plan, guided by the homeowners Sami and Sarita, to understand their lighting needs and to avoid overlighting. Availability of natural light was prioritised so that artificial lighting is not needed in any room in the daytime, with no part of the house further than four metres away from a window. But Lynnsay also worked to balance glazing for natural light with energy efficiency aims. “I am very careful with window design as glass is such a poor insulator,” she says. “So there is just one large double-glazed window/door in the main living space to allow a positive connection with the outdoors.” In other rooms, the windows were kept smaller, but wherever possible had two in each room, facing different directions to allow for direct sunlight to enter for longer periods, as the sun moves across the sky. Attached shading to the outside prevents excessive solar gain in the summer.
Task lighting solutions included an LED spotlight, ceiling-mounted to cast directional light for reading music at the piano, and LED strip lighting over a sewing desk. Dimming switches were installed to turn task lighting to mood lighting, or to night lighting, when desirable, rather than having separate light fittings for each function, and to reduce energy use.
Recessed downlights were used with discretion, and those that were used had sealed fittings, and allowed insulation around them to reduce heat transfer between internal spaces and the ceiling cavity.
Light fittings were selected for their functionality, but also to emphasise particular interior features. The stair light, for example, lights the steps below and the curve in the ceiling overhead. Fittings were also selected for fun, such as the bright yellow ceiling mount for Sami and Sarita’s young daughter, or for their sculptural quality, in the case of the pendant fittings over the dining table. Some fittings also include mobile app-controlled LED globes that can change colour.