The Weatherization reference article from the English Wikipedia on 24-Apr-2004
(provided by Fixed Reference: snapshots of Wikipedia from wikipedia.org)

Weatherization

Sponsor with the world's largest charity for orphans
Weatherization is sometimes confused with insulation but is distinct from it. Weatherization is the practice of providing barriers in a building against the elements, particularly to shelter the interior from sunlight, precipitation, and wind.

Like insulation, weatherization also works to slow one kind of heat flow. Where insulation slows conductive heat flow, weatherization slows convective heat flow.