Insulation the key to warmth Convenient, clean electric heating

Waimarino Bulletin, Volume 4, Issue 1, 3 June 1986, Page 8

Insulation the key to warmth Convenient, clean

electric heating

The world's energy resources are not inexhaustible. It has now become recognised how precious energy is. As it has become increasingly expensive to find and exploit new sources of energy so the cost of energy has risen dramatically over the last decade and a half. And the cost of energy will continue to rise. This rising cost of energy is reflected in the rising cost of home heating. Insulation is the single most effective measure you can take to reduce this lost energy and so reduce your home heating cost. Insulating your ceiling alone can save up to 50 per cent of your home heating cost. With walls, ceilings and floors insulated you can save 75 per cent or more of home heating costs.

You have only one chance for total insulation of walls, ceiling and floors, that is when you are building a new home. The savings made on heating costs will soon pay for the cost of insulating. The length of time this takes depends on a number of factors such as house design, living habits, heating mode, heating fuel, and can occur in the first year. Heat moves through air in two ways: by radiation from a hot surface and by air convection currents. Because of this, we have two types of insulation: • Reflective Insulation works on low radiating power of shiny surfaces such as aluminium foil. They work very much like a silver teapot which keeps the tea hot longer than a brown teapot.

These materials rely on having a still air space for full effectiveness and will also lose their value if the surface becomes dulled with time. If the air space immediately adjacent to the reflective surface is not still then heat loss by air convection becomes more important. Reflective Insulation is most commonly used as an underfloor insulating material in houses. • Bulk Insulation works by trapping many thousands of tiny pockets of air within the insulation. Heat will try to get across these pockets by both convection and radiation. But the heat transfer efficiency is reduced with each successive air pocket. This means that heat transfer is progressively reduced through the thickness of the bulk insulation until there is almost no heat loss from the cold side of the insulation.

All bulk insulating materials operate on the principle above but they differ in the material that makes up the boundary of the air pockets. Some use treated ground newspapers, other use plastic foam. Thick pink fibreglass Batts are made entirely of glass fibres bound together with a cross-linked thermosetting resin. Because they are made of inert glass fibre there is no risk in thick pink fibreglass Batts insulation. Thick pink fibreglass Batts are manufactured in NewZealand by AHI Fibreglass under licence to Owens Corning Fibreglass (the world's first and largest comercial producer of fibreglass insulation). AHI Fibreglass offers a full technical advisory service to assist in providing answers to general or specific queries which arise in the application of Batts.

Electric heating is clean, fast, efficient, por table, easy to use and safe. With the many types of electric heater available today one should seek advice on the model which suits your needs. Portable fan heaters are good for drying things such as clothes and shoes and for heating rooms where direct heat might be dangerous. Radiant heaters are the direct-heat-type using a polished reflector to push the heat forward. These are good for instant heat. Convection heaters warm the air by convection. They are panel types and usually have thermostats fitted to adjust room temperature. Infra-red heaters heat by infra-red waves. They heat the body only when waves strike the skin. Radiant fan heaters are good room heaters in which the combination of radiant and fan give good overall heat. Bathroom heaters are wall-mounted and reduce steam as well as warming the room. Night-store heaters use cheaper off-peak power which is controlled by power boards. The heater stores heat inside itself and radiates it long after the power is turned off.

Oil-filled heaters are good for heating children's rooms as they are safe. All electric heating can be controlled to turn on and off at set times by using timers which can be set manually. Thermostats can be set to a required temperature so that the room heat is maintained evenly. Electric blankets warm beds and are controlled by a manually set thermostat. There are also heating pads, heating mats and heating jackets. Electric heating heats water to a temperature set by thermostat, and is very efficient and convenient. Underfloor heating is built into a concrete floor and is controlled by thermostat.