As others pointed out, this older style is more suitable for masonry homes which might be less susceptible to mold and have enough thermal inertia to prevent pipe freezing.
On the flip side, you can make your house air-tight and use a heat exchanger to refresh the air while retaining the heat: that's the concept of Passive Houses[0]. Not suitable for cooling down hot & humid air (you'd have a condensation problem) but definitely an option for heating a home.
On the flip side, you can make your house air-tight and use a heat exchanger to refresh the air while retaining the heat: that's the concept of Passive Houses[0]. Not suitable for cooling down hot & humid air (you'd have a condensation problem) but definitely an option for heating a home.
[0] http://en.wikipedia.org/wiki/Passive_house