Home Design and Management 6th years

Systems and Services

Lighting

Good Lighting is important in the home because:

-  It prevents eyestrain

-  It prevents accidents

-  It can create atmospheres and moods

-  It can enhance features of interior design.

Natural:

-  Daylight

-  Suitable for most activities

-  The amount of light entering a room is dependant on several factors:

o  Aspect of room: South facing gets more light

o  Colour scheme: Dark colours absorb light, light colours reflect light

o  Windows: Number and size

o  Materials in room: Smooth, glossy surfaces reflect light and textured fabrics absorb light.

o  High ceiling: This allows for higher windows

Artificial:

-  Powered by electricity

-  Other sources of artificial light are candles, battery operated torches and oil lamps.

-  Classification of artificial lights .

Tungsten Fluorescent Compact

Filament Lamp Tubes Fluorescent Lights

Tungsten Filament Lamp:

-  Incandescent light is the closest to natural light

-  Clear, pearl, white or coloured glass

-  Contains nitrogen and argon gas

-  Tungsten filament coil runs through the bulb which resists the flow of electricity and gives off a white light as it heats up.

-  Lasts approx 1000hrs.

-  Measured in Watts from 25W to 200W

Fluorescent Tubes:

-  Long narrow tube which is coated with a fluorescent chemical (phosphor) and contains mercury and argon gas

-  At either end of the tube are electrodes which heat up when electricity is passed through them

-  These heated electrodes cause the mercury to change to vapour and this gives off an ultraviolet light when it reacts with the phosphor

-  Lasts approx 3000hrs

-  Lengths vary from 30cm to 2.5m

-  More light than filament lamps

-  It gives off more light than filament bulbs and lasts longer; however they can be more expensive and make noise while in use.

Compact Fluorescent Lights (CFL):

-  These are very energy efficient

-  Use 1/5 of electricity used by filament lamp but give same light

-  More expensive to buy however they work out cheaper in the long run due to low running cost and the length of time they last

-  Lasts approx 8000hrs

-  Ideal for use in areas which require light for long periods of time

Properties of Light:

Light travels in straight lines until it meets an obstacle. What happens to the light then can affect the brightness of a room.

-  Reflected light: This is where light bounces off bright, shiny surfaces. This helps the room to become much brighter.

-  Absorbed light: This is where light is absorbed by dark colours and rough surfaces making the room darker.

-  Diffused light: This is where light is scattered by non-reflecting surfaces into different areas of the room. This brightens areas of the room which do not

-  get light directly. E.g. Up lighters

-  Refracted light: Light rays are bent and change direction as they pass through transparent substances. This can be used in doors and bathrooms to give privacy and still add light to a room.

-  Dispersed light: This is where white light is broken into its 7 colours when passed through a prism. E.g. crystal lampshades.

Planning a lighting system:

-  When planning the design of the house natural light is a priority so housing plans should include as many windows as possible and all necessary light fittings and sockets.

-  Ensure lighting is sufficient for both the size and the use of the room. There should be more lighting in rooms which are used for eye-straining activities.

-  Use shades and pearl bulbs as this cuts down on glare

-  Consider safety

-  Lighting within a room should vary. All rooms can use natural during the day. Mix direct with indirect light e.g. central light with up lighters.

-  All light fixtures should suit the décor of the house

-  Consider maintenance, all fittings should be easy to clean and replace.

Lighting safety:

-  All fittings should be properly installed

-  Use correct strength of fuse and bulb wattage

-  Lampshades should not touch bulb

-  Bathrooms switches should be pull cord or outside door

-  Areas which are prone to accidents should be well lit e.g. staircases, exteriors steps