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 centimetres) 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.
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 centimetres) 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.
