– Fiberglass is a soft wool-like material that

is usually pink or yellow. It is used as insulation in

weatherproofing, and as textile material. Fiberglass is a glass

product, which is now favoured by most because of its

longevity and durability. It was originally used as a “safe”

substitute for asbestos. Fiberglass insulation was introduced

in the 1930’s. Fiberglass insulation is made by jetting molten

glass through tiny heated holes in a high-speed stream. The

resulting fibers are drawn very thin and to great length. The

fibers are then collected into a matte to produce fiberglass



Mineral Wool

– “Mineral wool” actually refers to two

different materials: slag wool and rock wool. Slag wool is

produced primarily from iron ore blast furnace slag, an

industrial waste product. Rock wool is produced from natural

rocks. Slag wool accounts for roughly 80% of the mineral

wool industry compared with 20% for rock wool. Given the

relative use of these two materials mineral wool has, on

average, 75% post-industrial recycled content. Wool

insulation is typically a batt-type product and is made from

recycled wool fibers, which are carded and joined together

using an advanced resin bonding process. There is also a

loose-wool form available, which can be blown into ceiling




– Cellulose is perhaps the best example of

recycled material used in insulation. Most cellulose insulation

is approximately 80% post-consumer recycled newspaper by

weight; the rest is comprised of fire retardant chemicals and,

in some products, acrylic binders. The biggest long-term

performance concern with cellulose insulation is possible loss

of fire-retardant chemicals. Because borates are water

soluble, they can leach out if the insulation gets wet.


Foam Insulations

– Polystyrene insulation can cause

irritation of the eyes, nose and respiratory system; headache,

fatigue, dizziness, confusion, malaise (vague feeling of

discomfort), drowsiness, weakness, unsteady gait; possible

liver injury; and reproductive effects. Many foam insulations

use recycled plastic resin such as that found in some extruded

and expanded polystyrene (EPS). Of the foam insulations,

polystyrene is easier to recycle than polyisocyanurate or

polyurethane since it can easily be melted down and reformed

into other products. The simplest recycling involves

crumbling the old EPS into small pieces and re-molding them

into usable shapes. Polystyrene used to be blown with

chlorofluorocarbons, or CFCs that destroy the earth’s

protective ozone layer. Now extruded polystyrene (XPS) uses

hydrochloro-fluorocarbons (HCFCs) that are not as

dangerous but can still be detrimental to the earth’s protective

ozone layer.

Two new types of foam insulations that do not use CFCs or

HCFCs are:



Icynene is a foaming agent that uses a mixture

of carbon dioxide and water. Though it does not have

polyurethane’s HCFC-related environmental problems, it

also has a lower insulation rating (R-value). Like

polyurethane, Icynene is foamed into wall cavities but

the resultant open-cell foam is soft, not rigid.


Air Krete:

Air Krete™ is inorganic foam produced from

magnesium oxide (derived from sea water). It is foamed

under pressure with a microscopic cell generator and

compressed air; no CFCs or HCFCs are used.



There are specialized firms that ate certified in removing

asbestos safely. You may be able to locate these firms

through your province or local health department. Do not

attempt to remove it yourself.


Tom Vattovaz Hamilton Region 905-572-1116 Canadian Home Inspection Services Construction Engineering Technologist, Niagara Region 905-356-1141 Registered Home Inspector, Other Areas 800-463-1141 Septic & WETT Certified