Insulation - Getting The Facts Straight
Studies prove that insulation works. What you save in energy bills depends on the age and type of house, existing insulation and other details. However, savings in insulated homes have been as much as 25 per cent--sometimes more. That's good value for your dollar, and homeowners have found that insulation quickly pays for itself with energy cost-savings. After that, it's money in the bank. Anytime of the year is insulation time, but you may get a better deal by having your insulation done in the spring or summer when contractors have fewer projects. But, as with any big purchase, investigate before you invest.
The 'R'-Value
Thickness isn't the only way to determine the effectiveness of insulation. Materials that are good for insulating purposes are poor at conducting heat. To provide a standard of comparison for insulation materials, "R-value" is used to measure resistance to heat transfer. The higher the R-value per inch of insulation, the more effective the material in resisting the escape of heat. When you buy home insulation, it's a good idea to look for the manufacturer's instructions on the insulation packaging to make sure it meets the standards
Types Of Insulation
Insulation has come a long way since the days when newspaper, sawdust or woodshavings were used. The following are common examples of modern insulation.
LOOSE-FILL INSULATION: These include glass fibre, cellulose fibre, mineral fibre and vermiculite. Some of these, such as glass and mineral fibre, may be blown as well as poured. The R-value per inch varies from 2.1 to 3.6 depending on the type and insulation method. 'BATT' OR
BLANKET INSULATION: This is normally made from glass or mineral fibre. Batts come in different widths and thicknesses. The R-value per inch varies from 2.9 to 3.3 according to the type. The total R-value of the batt depends on the thickness.
FOAMED INSULATION: Polyurethane foam is a relatively new product and must be installed in walls by factory-trained installers. Complex equipment and mixes are used, and improper installation could cause damage to your house. The R-value of polyurethane foam is about 6.0 per inch. This material hardens almost immediately, can catch fire and should be completely covered in the manner described in the Ontario Building Code.
Polyurethane foam is now available pre-mixed in pressurized containers. These are either hand-held spray cans for smaller jobs such as sealing of drafts around window frames, or large "floor" canisters for heavier use. When choosing the type of insulation you need, think about resistance to water, bacteria and household pests, the cost, ease of application and perhaps rigidity/flexibility. Remember, there are many brand names of insulation material - so you should be able to find one that suits your needs whether you or your contractor do the job.
Vapor Barriers And Ventilation
Under winter conditions, the warm moist air inside heated spaces passes into the cold outer areas of the building and condenses in roofs and walls. To control the movement of moisture into other areas, vapor barriers should always be installed on the warm side of the ceiling or wall. Good ventilation in attics and roof spaces helps keep the insulation dry and retains its effectiveness, prevents mould growth, corrosion and wood rot and reduces paint peeling problems. Even houses that have a properly installed vapor barrier allow some leakage into the walls and attic. In all cases, moisture must be allowed to escape to avoid problems.
Outside walls generally allow vapor to escape freely as they are not airtight--but attics require ventilation. There should be one square foot of unobstructed ventilation opening for each 300 square feet of ceiling. These openings should be located to establish good cross ventilation with one-half the required vents to be in the soffit and the other half on the roof near the ridge or high in the gable ends. Don't forget that every home needs a good supply of fresh air. Just as we need air to breathe, fuel-burning appliances need air to operate safely. A special duct to supply outside air may be needed.
'Siding' has become a popular way of giving homes a face-lift. As well as reducing maintenance and blocking drafts, installing siding may provide a good opportunity to have additional insulation blown into woodframe or brick-veneer walls--a heat-saving benefit which will partially make up for the cost of the siding.
Installing 'siding' is a big investment, so take some time to evaluate both the product and the company. 'Siding' is available in aluminum, steel, various types of vinyl, wood and wood products (hardboard). When deciding what kind to use, examine your reasons for having it installed. Don't choose a siding which requires regular washing, painting or staining if easy-to-maintain siding is what you want. Other criteria that may affect your choice are cost and insulation value. Contrary to many sales claims, most siding provides only a little insulation. 'Siding' with insulation backing may increase this, but not to the extent that insulating your walls would. Metal or vinyl sidings should be vented to allow the walls to breathe. Information for do-it-yourselfers is also available from these sources and at public libraries. 'Siding' glossary-before you begin, get to know these basic siding terms:
FLASHING: a waterproof material such as sheet metal generally applied to edges and projections such as chimneys and roof peaks to keep out the rain.
CORNER POST: usually two vertical boards a few inches wide which wrap around a corner for the horizontal siding sections of two adjoining exterior walls to butt against it. This avoids the difficult problem of having to mitre siding at corners.
J-CHANNEL: a metal piece shaped like a "J" fastened to a masonry wall at intervals. Siding is then seated in it in such a way that the "J" is hidden and avoids the problem of nailing into the masonry.
SOFFIT: underside of a roof overhang.
FASCIA: vertical face of roof edge.
The Product Warranty 'Siding' manufacturers usually guarantee their products against defects. However, this doesn't cover damage caused by mistakes when it's put on your home. The length of the manufacturers' warranty depends on the material. Most metal sidings carry a 20-year guarantee. Read the small print on the warranty very carefully. On some, the guarantee period is pro-rated, which means the amount that the manufacturer will pay for product replacement decreases every year. You should also find out what the guarantee on the exterior finish covers. Some are not guaranteed against normal fading, chalking or pollution, which are the most frequent problems. Some warranties require the owner to clean the siding regularly to maintain warranty protection. A warranty may be transferable to a new owner. It is advisable to check with the company.
Despite all your precautions, you may still find yourself the victim of unscrupulous business practices. If this is the case, you have several choices. Under the Consumer Protection Act, you can cancel a contract for more than $50 if it was signed in your home. Send a registered letter or hand deliver it to the company within three days of the signing date.
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