Following the law of physics, heat flows from warm to cold. So when you are heating your home the warm air naturally tends to go to the cold areas of your home. The exterior walls, your attic and basement or crawl space are the main areas of temperature transfer. In the summer, the flow is reversed, with the warm outside air moving towards the cooler inside air.  Insulation is your only defence against preventing this transfer of heat and cold. 

The “R” value, resistance to heat flow, is the rating of thermal resistance.  The higher R value protects your home from loss of energy through heat flow.

 There are many types of insulation products available, the most common are fibreglass, rock wool,  cellulose and perlite or vermiculite. Fiberglass comes in loose fill or batts and can be pink, white or yellow. Rock wool is usually grey in colour with black specks.  There is also a rock wool green colour batt. Vermiculite or perlite is usually only found in older homes.  There is a concern with vermiculite with asbestos.  Expanding naturally occurring minerals in a furnace produces them. The resulting granules are non-combustible and are commonly poured-in-place. Most homes with vermiculite have to declare this when selling home. To check your insulation first check the attic to see what and thickness of insulation is present.  Check your soffit vents at sides and ensure that there are rafter baffles installed or plywood is in place to allow air movement from soffits. Next check garage or other unheated spaces to see what type of insulation you have in wall spaces. After noting type of insulation and thickness you can begin calculating your R value for each area of your home. 

Fiberglass Insulation Fiberglass insulation is the most commonly used product for most residential applications. It consists of blend of soda ash, ground sand, and boron, and it is available as batt insulation with a vapor barrier, or blanket insulation, which is unfaced so that a separate vapor barrier can be installed only when it is needed. The R value varies greatly. It can be as high as R38. Blanket insulation comes in 4-foot and 8-foot lengths, and both the batt and blanket types are available in 16-inch and 24-inch widths. Typically, 3 1/2 inch batt insulation with an R11 or R13 rating is used to insulate in wall cavities and 6-inch insulation with an R20 rating is used in ceilings and attics. 

Rock Wool InsulationRock wool insulation in a house as well as in industrial and commercial applications.  It comes from slag, a byproduct in the manufacture of steel. Its melting point is twice that of fiberglass. Rock wool is very dense, and this characteristic makes it more sound-retardant than fiberglass insulation giving it a hight STC rating. Rock wool insulation is an appropriate choice in sound deadening applications.  

Cellulose Insulation Cellulose insulation is made of  recycled paper and is mainly used in wall and ceiling cavities. Cellulose insulation has been chemically treated to make it fire and insect resistant. Cellulose insulation has excellent sound-proofing qualities, as does rock wool, and its R value decreases significantly after it gets wet, like Fiberglas insulation. After it dries, the texture of cellulose insulation is like tissue paper, and, it becomes ineffective as an insulating material and should be removed and replaced. Check for vapour barriers, exhaust vents, cracks around vents or piping, clearance around “B” vents ( 1 inch required) and any other areas where moisture or heat loss may occur.  Foam insulation is an excellent product for sealing these areas. Before you run out to your local building supplier and buy bags of insulation and rent a machine to blow it in, check with a local insulation installer.  Sometimes you can have the insulation installed for below or around the same price of you doing it yourself.

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