Reducing Heating Costs By Insulation
IF YOU are like most people, you look for ways to save money on household expenses. Did you know that insulation can help you to do just that by reducing home heating costs? Even if you live in a warm climate, insulation will help to cut expenses, since it is generally agreed that more energy is required to cool a home in summer than to heat it in winter.
But how will insulation save you money? Inflation, record-breaking extremes in temperature and fuel shortages all have contributed toward increasing the price of maintaining the comfort level of your home. Insulation will aid you to keep that comfortable level at a lower cost.
What Insulation Accomplishes
But what does insulation really do? Since no heat is generated by the insulation itself, how does it work? Simply stated, it slows down the movement of heat. Heat is like a river in that it always flows in one direction—from warm surfaces to cooler ones. Hence, heat will flow out of a house in cold weather and into it when temperatures soar. This flow takes place in three ways: by conduction, by convection and by radiation. Conducted heat travels through solids such as bricks and concrete, while convected heat is transmitted in fluids. Thus a wooden-frame house with air space in the walls, or one that is not insulated, will lose heat by convection, since air acts like a fluid. Radiant heat travels through space (as in the instance of the sun) and heats the object it strikes (as in the case of the earth).
Experimentation indicates that air is a poor conductor of heat. Therefore, what insulation accomplishes is this: It makes tiny traps or pockets of still air, and these slow down heat transfer. Also, insulation material itself is a poor conductor.
Insulation material comes in several forms. It may be a granular material or loose pieces of mineral wool about the size of small hen’s eggs. Packed in bags, it is usually placed in level places, such as attics or crawl spaces, where it will lie undisturbed. The fluffy quality, produced by the pieces being on top of one another, creates the spaces of dead or noncirculating air. Fiber glass is often used in side walls and is usually glued to a paper or foil backing, which is secured to the walls to hold it in place. These are called blankets or battens and they come in varying widths and thicknesses. More rigid pieces of foamed plastic may also be used, but in each case the trapped air pockets result in the insulation properties. The notable exception is the use of metal foil to reflect radiant heat.
By contrast, solid building materials are poor insulators, transferring heat more quickly. Reinforced concrete, steel, concrete blocks, bricks, plaster and even wood, although required for the structural support of a building due to their strength, should always be used with a suitable insulation for maximum heat retention. Some authorities illustrate this need with the claim that it would take a wall of bricks 99 inches (251 centimeters) thick to equal the insulation capability of only two and three fourths inches (7 centimeters) of polyurethane!
Making Insulation Work for You
The need for insulation is virtually unquestioned, and so, in modern construction, such material is always included as part of a new building. But the amount and the type to be used varies from one area to another and may even vary among insulation contractors and engineers. A widely accepted amount is six inches (15 centimeters) of fiber glass in ceilings and attics and three and one half inches (9 centimeters) in side walls. However, in view of fuel costs and shortages, some experts now are recommending almost twice these amounts. Additionally, areas formerly left uninsulated, such as basement walls and floors over unheated parts of the house, are now receiving attention. Also to be remembered is the fact that some insulation materials are more efficient than others. For example, the same insulation is achieved from three and one half inches (9 centimeters) of extruded polystyrene as from six inches (15 centimeters) of fiber glass.
When cost is an important factor in new construction, it is not wise to eliminate or drastically reduce the insulation budget. Most of the cost of insulation is in the product itself, not in the labor to install it. Furthermore, it will pay for itself in fuel savings in just a few years. In the United States, some lending agencies give favorable consideration on loans made for the purpose of constructing “super insulated” homes. The theory behind the loan is that operating expenses will be reduced and the savings from fuel not used can be applied toward the repayment of the loan.
More savings can result in heating and cooling a new home if it is built with insulated windows, keeping their size and number to a minimum on shaded sides of the house and making them larger and more numerous in sunny areas of the building. In warmer climates, shade trees or other devices may be necessary to reduce the amount of sunlight striking the building, as this will decrease the heating of the house by solar radiation during the summer months.
Even in older homes, insulation can make a difference in heating and cooling bills. Can attics or crawl spaces be insulated? Insulation contractors can foam liquid plastic into wall cavities where it will solidify and provide a barrier against heat loss. Tight-fitting storm windows and doors help, too. Weather stripping also aids. According to a U.S. Department of Health, Education and Welfare publication, “under average conditions complete weather stripping will reduce 15 to 20 per cent the amount of fuel needed for a house not especially insulated.” Not to be forgotten is the space at the bottom of the door. Closers on doors will keep them shut and will cut down on drafts.
Wrapping heat-carrying ducts and pipes with a suitable insulation material will reduce heat loss. Keeping furnaces, boilers, chimneys, and fuel and air filters clean is necessary in heat conservation. In older homes, all such improvements will increase, to some degree, the resale value of the house. Of course, they may also increase the assessed value and, hence, the property or real-estate taxes.
If you are a homeowner who can spend only a minimal amount, have you thought of lowering high ceilings? This will require less heat to warm the room, since its volume is reduced. However, in homes with a single thermostat, care should be taken in the room where it is located. If only that room has the ceiling lowered, it will heat more quickly than the others and cause the furnace to shut down before the rest of the house is warm. If you do not own your own home and cannot lower the ceiling, you will find that floor rugs not only beautify but add somewhat to the insulation of a room.
During the winter, tenants who pay their own heating bills will find that curtains and window blinds can be opened to allow sunshine into a room, thus heating it by means of radiant energy. When the sun no longer shines through the window, the blinds can be closed and the curtains drawn to prevent heat loss through the glass. In warm climates, this closing of the blinds is done to reduce costs in cooling the home in summertime.
Another method used in winter is to lower the thermostat at night and put on extra blankets while sleeping. Some use electric blankets. But, in either case, you may need an old-fashioned nightcap to keep your head warm. Of course, you can also close off extra or unused rooms.
Disadvantages
There are disadvantages that must be considered in well-insulated homes, especially in winter. Unless doors are opened periodically, as in normal use, the amount of usable oxygen can be greatly reduced. Such a lack of sufficient oxygen is an obvious health hazard to anyone, but especially to the very young and to those who may be ill or elderly, all of whom may not easily detect such oxygen depletion.
Another disadvantage is the temptation to raise the thermostat, feeling that the insulation will retain the heat. It should be remembered that no insulation is 100 percent effective. Insulation does not stop heat loss; it only slows it down. Further, such an attitude is wasteful and is not conducive to reducing home heating costs.
Rigid foam lends itself to insulating existing homes, as when glued to interior stone or brickwork. But it has one serious disadvantage, which applies to both styrene and urethane foam. It is combustible and must be covered with at least one half inch (1.3 centimeters) of plasterboard. The same can be said of loose cellulose insulation, since it is ground newsprint and, unless properly treated with flame retardants such as formaldehyde, it could be a fire hazard. Even then, these retardants can dissipate in time; so extreme caution is advised.
Plan Ahead Now
If you decide to insulate your home, pick the time most advantageous to your area. Some companies may either sell or install insulation at a reduced rate during certain times of the year when their business is slow.
If you plan to do much of the work yourself, a further point can be made about a vapor barrier. This is a membrane that is placed between the insulation and the heated surface. The reason for it, states Popular Mechanics Illustrated Home Handyman Encyclopedia and Guide, is that “moisture-laden air inside the house slowly penetrates the plaster and insulation and condenses to water or ice when it comes in contact with the cold inner surface of an exterior wall or roof.” Such condensation can result in “rotted wood, peeling paint, damage to inside walls and ceilings, and damage to insulation.”
Since considerable time and money can be invested when insulating a house, if you decide to do your own work, take time to read current books or periodicals on the subject. Local building codes should be researched to be sure that you will not violate the law. Carefully plan out your work schedule in advance. In return for all your hard work and investment, proper insulation will reduce home heating costs.