Air temperature and moisture content

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2 - 108 Building services are the plumbing, electrical, heating and other equipment that provide much of the amenity of a modern home. Communications services, telephones and the Internet also connect occupants to the community. The support provided by building services may be especially important to the elderly and some people with disabilities. Air temperature and moisture content A home is an environment filter. It provides shelter but it allows the entry of air, sunshine and heat to make a comfortable internal environment. The World Health Organisation recommends a minimum indoor temperature of 18 C. Women tend to prefer a slightly higher room temperature than men. Below 16 C there is an increased risk of respiratory problems and below 12 C there is an increased risk of cardiovascular strain. A relatively inactive person or a person suffering from circulatory problems will feel uncomfortably cold at higher te.mperatures than an active person, and will require a minimum room temperature 2 C to 3 C higher. Similarly, some elderly people and others with disabilities feel more discomfort in the heat than others.

3 109 Even in a heated room, people who spend much of their time seated such as those in wheelchairs may suffer cold feet. Many heating systems do not distribute the heat evenly from floor to ceiling, as illustrated in figure Where heat is inconsistently distributed, ceiling fans can be used to redirect warm air from the ceiling or infloor heating installed to provide warm air at floor level. Principal factors contributing to discomfort are: dampness heat loss inadequate heating or air-conditioning. Dampness can enter a house in the form of water vapour either from the sub-floor space or from exhaled moisture and discharged steam within a house as illustrated in figure To corl)bat the accumulation of moisture inside a house, ensure that the house is well ventilated even when its windows are closed, and that there is sufficient air and steam extraction from the bathrooms and kitchen areas. A new concrete slab contains much water and should be allowed to dry thoroughly before a house is occupied ~ ~.,~~..... I moisture condenses moisture ~. on windows condenses on water can er ~ walls and : subfloor are; ceilings causing outside if th 17 0 damp and ground slope free water b can pond in 1 ~::::::~:;;::;~=:::mo:u~ld~====~==~~ towamsthe 16 0 hollows damp earth 15 moisture enters the house from the ground 40 litres per day for the average house Temperature gradients in Figure 1 Dampness entering a house a heated room

4 Most heat transfers occur through the roof, but heat losses will occur through any part of a building that is not well insulated or through any poorly sealed joint that allows a draught through. In addition to insulation, double glazed windows can be used to reduce heat loss. ~ 20% t hrough 40% through the roof the wi ndows 30" II - I~ 10 Via ~ 101. floors Figure 14.4 illustrates the conversion of a draughty, poorly insulated, damp house to one with the correct prerequisites for heating and cooling. The renovation of an existing building to improve its ventilation, insulation and draught management may require: controlled ventilation to be increased if the house is too air tight gaps to be filled to limit draughts the installation of insulation in accessible roof and wall spaces the installation of insulation to the underside of timber floors the installation of full-height, high quality thermal drapes and pelmets. Typical heat loss from an uninsulated house fi ~ a high level of insulation (R3) t o t he accessable roof spa ce: this gives thl.: best return heavy drapes reduce heat loss t night reduce draughts around wind ows and doors good extract f rom kitchen and bathroom consider retrofitt ing insula t ion to the ceiling l e roofs ~, 1 of u~4ccessib f it insulation in wa lls where relining is necessary Enhancing an existing house most concrete floors have a satisfact ory level of insulation

5 111 Heating and air-conditioning the home There are numerous space heating and air-conditioning systems available. In order to make an informed choice it is a good idea to consider: how effectively and uniformly it will heat or cool the space how safe the system is for the user how easy the system is to operate the rooms or spaces that may need additional heating or cooling. Some people are not able to move or react quickly or may not have full sensation in their limbs. These people may be at risk of injury from contacting hot surfaces. Convector panels, electric radiators, piped radiators and their pipes should be shielded if they reach a temperature above 43 C. Rooms that are frequently used such as bedrooms and living rooms may benefit from top-up heating. People with limited mobility may spend longer in the bathroom than others and may benefit from additional bathroom heating. In-floor Heating In-floor heating uses hot water pipes or electri9al cables cast into a concrete floor to warm the floor and radiate heat into the room. The system provides heat where it is most needed for sedentary people and children. However, in-floor heating cannot heat a room rapidly. It provides excellent background heating but may need to be supplemented with additional, faster heating on occasions. Piped radiators This efficient system consists of radiating panels heated by water circulated from a central boiler. The radiators occupy space under windows or on walls and can interfere with the layout of furniture and obstruct space in hallways. Low temperature electric radiators Usually oil filled, low temperature electric radiators offer an efficient and comfortable heat source with a good response time. They can be moved and plugged into convenient power outlets. Convection fan heaters Convection fan heaters are relatively inefficient because they warm the air and not the person or the structure. They are best suited for quick-response, short-term heating for small areas and are ideal for bathrooms.

6 Gas heaters Gas heaters, with a flue to the outside, provide an economical and comfortable source of heat by both radiation and convection. They are relatively unobtrusive and can be mounted flush with the wall. Unflued gas heaters and portable bottled gas heaters are not recommended as they discharge burned gasses and large amounts of water vapour into the house. The water vapour may later cause condensation and moisture problems. Portable electric bar radiators Portable electric radiators can be dangerous and are not recommended. Solid fuel fires Open fires create a welcoming ambience but they have many drawbacks: they are uneconomical, losing most of their heat up the chimney chimneys can be draughty they require fuel to be stored and carried into the house they need regular cleaning they may not be suitable for many people with disabilities. Wood-burning stoves Wood-burning stoves require almost as much maintenance as open fireplaces but return far more heat. Some models can also be used to heat water. Ducted heating and cooling With ducted heating, air is warmed or cooled at a central unit and pushed through ducts to the outlet, usually at or near floor level. One disadvantage of ducted systems is that the speed of air movement can cause excessive dust circulation. Air conditioning In warm climates or climates with hot, humid summers, air conditioning may be necessary to provide year-round comfort. Air conditioning can provide relatively precise indoor temperature control, producing cooler and drier air in summer and warmer air in winter

7 Hot water services Plumbing standards applied across Australia limit the delivery temperature of hot water to bathroom fittings in the home. The standards, which apply to all new hot water distribution systems, are designed to guard against scalds and burns in the bath or shower. Under these standards, the delivery temperature of hot water through any domestic bathroom tap, faucet or shower rose must not exceed 50 C. Aged care facilities and supported accommodation for disabled persons must limit the temperature of hot water in the bathroom to 45 C. This lower temperature may be more suitable for some elderly people and some with disabilities living in their own home. Restricting the temperature in kitchens and laundries is optional. The temperature of the hot water should not be limited to the required temperature by setting the thermostat on the water heater or storage unit. Rather, a temperature valve just before the water outlet should ensure that enough cold water is let in from the mains supply to bring the hot water to the required temperature. The water heater and storage unit must always be set at a minimum 60 C to prevent the growth of bacteri a. The heater should be well insulated to avoid wasting the stored heat. Smoke alarms Smoke alarms are required in all homes and provide an invaluable warning to occupants in the event of a fire. Smoke alarms are available in two principle models, those that are battery operated, and those that are connected to a mains supply. The mains powered devices also have a backup battery. New homes must have smoke alarms connected to a mains supply. Smoke alarms can be interconnected so that if one alarm senses smoke, all alarms go off. As smoke alarms are ceiling mounted, elderly people and those with disabilities may have Battery operated_smoke alarm. difficulty testing the devices and replacing batteries. In these circumstances it is best to install a smoke alarm interconnected system as part of a domestic security system. Smoke alarms need to be strategically placed to ensure that they quickly detect a fire and alert the occupants: They should be located on the ceiling between the living areas and outside bedrooms. Often a hall is the right location. Most homes will need more than one alarm. If the homeowner has a hearing impairment, flashing lights can be connected to the detection system as a supplementary visual alarm. 113

8 Lighting Artificial lighting can define the ambiance of a house and is important for safety. Adequate lighting becomes increasingly important as a person ages, with some older people requiring two to three times more light than younger people for optimal visibility. There are three basic types of lighting: background, task and decorative. Decorative lighting accents certain features or draws attention to the fitting itself. To avoid the glare of looking directly onto a light bulb it is best to shade it with a light fitting or place it in a location outside the normal sweep of the eyes. Light shade for background lighting. Background light is the ambient light in a room. Ideally, it is sourced from uplighters and wall washers, which use the ceiling and the wall as reflectors. These fittings illuminate without glare. It can be useful to have background lighting on a dimmer switch so the light intensity can be varied to suit different occasions. ~ackg round lighting l :ource task lighting screened by shelf Task lighting provides focused illumination for particular activities in set locations. It improves visual clarity and offsets tiredness. Background lighting and task lighting.

9 115 dcor handle; flight switch same height as door handle -== ~ T 500mm mm r socket outlet -* ~L rrjl LQJ switches with neon indicators 2 switches per plate preferred o Q switch with dimmer control Preferred positions of light switches and socket outlets Figure 14. Large switches Light switches Design the electrical installation so that there will be sufficient switches and outlets in the right locations for current and future needs. The preferred height for light switches is 900mm to 11 OOmm and aligned with door handles, as illustrated in figure They should be placed near the entrance to a room and at the same side of the door as the door handle. Switches must be easy to use. Large rocker switches are ideal. Illuminated switches help people find them in the dark. Too many switches on one plate can create confusion, and two or three switches on a single plate is the maximum recommended. In some cases, it may be appropriate to consider the use of proximity switches that operate the light on sensing the presence of a person.

10 This type of device is particularly useful for stairways and halls and for external lighting to entrances and garages. An alternative is a remote control switching device, which works in a similar manner to a 1V remote controller. Two-way or three-way switches are also useful in stairways, corridors and bedrooms and for controlling exterior lights to entrances and garages. Figure 00 Proximity switch '" o Power outlets A house needs to be equipped with enough easily accessed electricity outlets to avoid the need for extension cords and overloaded circuits. Extension cords can be a trip hazard. Electrical outlets should be doubles to avoid the later use of adaptors. For ambulant people, power outlets on walls behind benches should be 1OOmm to 300mm above the bench. For people in wheelchairs and other people who have limited reach, outlets should be mounted as shown in figure 14.10, on the bench front or on the wall 500mm out from a corner. Power outlets on walls should be installed at a consistent height throughout the house between 400mm and 500mm above the floor and located 500mm from a corner. This height, illustrated in figure 14.6 on the previous pag~, is a compromise. It may mean that outlets are too low for some people but not so high that the draped cord is a hazard. Where possible, locate power outlets-where they will not be obstructed by furniture. If a power outlet is to be placed above a bench-top standing persons will find it generally accessible between 100mm and 300mm above the bench. For people in wheelchairs and others with a limited reach, outlets should be mounted at the bench front and 500mm away from a corner. Figure 14.9 Remote control light switch

11 11 7 socket outlet on side wall is Communications Modern communications are almost essential for everybody but can be a lifeline.for many people with a disability. Cordless and mobile telephones make it possible for people to telephone from anywhere in a house. The position of the main telephone point is not so importart. For those who have difficulty holding a phone in one hand and dialing with the other, a fixed keypad should be installed in a suitable location in a house. Answering machines can be most useful for people who are unable to move quickly in order to reach the phone. Fax machines can be useful for people with a hearing impairment. Figure 14.1:i Socket outlets on a bench-top

12 Computers with Internet facilities allow people to communicate across the world, gather information and work from home. To provide for Internet and access, power outlets and a telephone jack or cable connection will be required at each workstation. An additional telephone line may be needed in some installations. An intercom system, with speaker and call points strategically placed around the house, can be useful in a multioccupant home, particularly where one occupant frequently requires the assistance of another. If a person can reach a call system in a time of crisis, it allows that user to sound an alarm that alerts others. These systems may be operated using a push button on a flexible cable, a pull cord in a toilet or shower area, or a wall-mounted button. Home automation systems Appliances, security systems and doors in a home can all be controlled from one central point or controlled remotely, even using the Internet. Home automation systems or remote technology can be used to control: entry gates, driveway lighting and garage doors from inside a car the locking and unlocking entry doors light switching and dimming cooking appliances heating systems that monitor internal and external temperatures and adjust for day and night. Security systems Domestic security systems can be useful and reassuring, but they can be too complex for some people to operate. They may need to be individually designed to suit the particular home occupants. Central vacuum cleaning - Portable electric vacuum cleaners are heavy to carry and can be difficult to manoeuvre. Vacuum cleaning systems with a central motor and dust receptacle located outside the house can be easier to operate. A central vacuum system uses a lightweight hose that plugs into wall mounted vacuum outlets placed throughout the house. These outlets should be located 300mm to 500mm above the floor. As the central motor is housed outside: the hose and nozzle are relatively light and easy to manoeuvre vacuuming is quieter the system does not exhaust dust back into the room